Merge remote-tracking branch 'upstream/main'

# Conflicts:
#	docs/REPOSITORIES.md

.gitignore

@@ -21,6 +21,8 @@ test_bytecode.dart
 # Dart/Flutter build output in root-owned test fixtures.
 **/.dart_tool/
 **/build/
+**/__pycache__/
+*.pyc
 
 # Local editor/OS files.
 .DS_Store

.gitmodules

@@ -1,6 +1,6 @@
-[submodule "dart-sdk-new"]
+[submodule "dart-sdk"]
-	path = dart-sdk-new
+	path = dart-sdk
-	url = https://git.tonycloud.org/dart-lang/sdk.git
+	url = https://github.com/tony-cloud/dart-sdk.git
 	branch = tonycloud/dev
 [submodule "depot_tools"]
 	path = depot_tools
@@ -8,8 +8,8 @@
 	branch = main
 [submodule "flutter"]
 	path = flutter
-	url = https://git.tonycloud.org/flutter/flutter.git
+	url = https://github.com/tony-cloud/flutter.git
-	branch = shorebird/dev
+	branch = tonycloud/dev
 [submodule "shorebird"]
 	path = shorebird
 	url = https://git.tonycloud.org/flutter/shorebird.git

README.md

@@ -9,15 +9,15 @@ platform scripts in this root repository.
 
 | Path | Role | Remote | Branch |
 | --- | --- | --- | --- |
-| `dart-sdk-new` | Dart SDK fork with AOT patch runtime work | `https://git.tonycloud.org/dart-lang/sdk.git` | `tonycloud/dev` |
+| `dart-sdk` | Dart SDK fork with AOT patch runtime work | `https://github.com/tony-cloud/dart-sdk.git` | `tonycloud/dev` |
-| `flutter` | Flutter fork used by app and engine integration tests; engine sources live under `flutter/engine/src/flutter` | `https://git.tonycloud.org/flutter/flutter.git` | `shorebird/dev` |
+| `flutter` | Flutter fork used by app and engine integration tests; engine sources live under `flutter/engine/src/flutter` | `https://github.com/tony-cloud/flutter.git` | `tonycloud/dev` |
 | `shorebird` | CLI, protocol/client packages, open patch tools | `https://git.tonycloud.org/flutter/shorebird.git` | `main` |
 | `shorebird-server` | Self-hosted CodePush/auth/management server | `https://git.tonycloud.org/flutter/shorebird-server.git` | `main` |
 | `updater` | Runtime updater and patch package tooling | `https://git.tonycloud.org/flutter/shorebird-updater.git` | `main` |
 | `depot_tools` | Chromium/Dart checkout tooling | `https://chromium.googlesource.com/chromium/tools/depot_tools.git` | `main` |
 
 The Dart SDK checkout has additional gclient-managed dependencies under
-`dart-sdk-new/third_party`. They are intentionally not top-level submodules.
+`dart-sdk/third_party`. They are intentionally not top-level submodules.
 
 ## First Checkout
 
@@ -41,6 +41,97 @@ By default the bootstrap scripts run `gclient sync`, which can download a large
 toolchain/dependency set. Set `SKIP_GCLIENT_SYNC=1` when the checkout is already
 synced or when you only want source-level tests.
 
+## GitHub CI
+
+The root workflow `.github/workflows/open-shorebird-ci.yml` is the upload-ready
+CI entry point for the combined workspace. Default push and pull request runs
+execute source-level checks and build distributable CLI/server artifacts:
+
+- compiled `shorebird`, `open_aot_patch_tools`, and `artifact_proxy` archives
+  for Linux x64, macOS x64/arm64, and Windows x64
+- public updater `patch-*.zip` mirror artifacts for the CLI cache
+- `mirror-metadata` with `artifacts_manifest.yaml` for the artifact proxy
+- self-hosted `shorebird-server` archives for Linux, macOS, and Windows
+
+Default push and pull request runs also build the large SDK and engine outputs:
+patched Dart SDK archives for Linux x64 and macOS arm64, Linux x64 desktop
+engine artifacts, Android arm64 engine artifacts, Flutter web SDK artifacts,
+and Apple iOS/macOS engine artifacts. A successful full SDK run also uploads
+`open-shorebird-artifact-mirror`, a publish-ready mirror archive assembled from
+the produced patch-tool, metadata, engine, and web artifacts, plus
+`open-shorebird-release-manifest`, a checksum-verified provenance index for the
+CLI, server, SDK, engine, and mirror archives. Manual `workflow_dispatch` runs
+keep `full_sdk_build=true` by default; set it to `false` only when you want a
+source/CLI/server-only run.
+Use `scripts/validate_release_manifest.py` to audit a downloaded manifest
+against the downloaded workflow artifacts before publishing or mirroring them.
+The wrapper `scripts/verify_downloaded_release_artifacts.sh` runs that manifest
+sidecar check, verifies the mirror archive sidecar, and validates the extracted
+artifact mirror from a downloaded workflow run.
+Before pushing the workspace and submodule forks, run
+`scripts/verify_upload_readiness.sh`; it fails if any required CI support file
+is untracked or if a required root/submodule checkout still has uncommitted
+changes.
+After upload, `scripts/verify_hosted_full_sdk_build.sh --repo owner/repo --ref main`
+dispatches the hosted full SDK workflow, waits for it, downloads artifacts, and
+runs the downloaded-release verifier. It uses `gh` when available, or the
+GitHub REST API with `GITHUB_TOKEN`/`GH_TOKEN`, `curl`, `jq`, and `unzip`.
+The heavy SDK/engine jobs default to managed GitHub-hosted runners
+`ubuntu-latest` and `macos-latest`, then run an early disk-capacity preflight.
+Override `linux_heavy_runner` / `macos_heavy_runner` only when you want larger
+or self-hosted runners. The dispatch inputs `sdk_min_free_disk_gb` and
+`engine_min_free_disk_gb` control the preflight thresholds.
+The CI contract is validated by
+`scripts/verify_ci_workflow.sh`; it rejects `dart_dynamic_modules=true`,
+legacy `aot-tools.dill` publishing, missing checksum sidecars, and missing
+required artifacts.
+Manual `workflow_dispatch` runs with `run_runtime_smokes=true` run the Android
+and Linux seeded runtime patch smokes on provisioned runners. These jobs are not
+part of default push/PR CI because they require local engine build directories;
+the Android smoke also requires an attached device or emulator.
+The open CLI defaults vended Flutter installs to this workspace's open Flutter
+fork and can be pointed at a future GitHub mirror with
+`SHOREBIRD_FLUTTER_GIT_URL`. When no `base_url` or hosted URL override is
+configured, API/auth traffic defaults to the local self-hosted server at
+`http://localhost:8080` instead of Shorebird's hosted service.
+The bundled updater library uses the same default when `shorebird.yaml` does not
+include `base_url`.
+CLI-managed patch-tool artifact downloads default to the local open mirror root
+`http://localhost:8080/artifacts`; set `SHOREBIRD_ARTIFACT_BASE_URL` for a
+public mirror populated with the CI-produced `patch-*.zip` files and
+`artifacts_manifest.yaml`. The patch artifacts and manual engine artifacts
+include publish-ready `shorebird/` mirror subtrees that can be copied to that
+same mirror root. Full SDK workflow runs upload the already assembled
+`open-shorebird-artifact-mirror` archive; after downloading workflow artifacts
+manually, use
+`scripts/assemble_artifact_mirror.sh <downloaded-artifacts-dir> <mirror-root>`
+to merge those subtrees, reject conflicting artifact bytes, validate
+`artifacts_manifest.yaml` overrides, verify all platform `patch-*.zip` files,
+and write missing checksum sidecars. If your open engine revision differs from
+the upstream Flutter engine revision used for unchanged artifacts, set the
+workflow `base_flutter_engine_revision` input when generating mirror metadata.
+Vended Flutter commands receive `FLUTTER_STORAGE_BASE_URL` from
+`SHOREBIRD_FLUTTER_STORAGE_BASE_URL`, falling back to
+`http://localhost:8080/download.flutter.io` for local self-hosted artifacts.
+The Flutter fork itself uses that same open mirror as its default engine and
+Android Maven artifact host when `FLUTTER_STORAGE_BASE_URL` is unset, including
+its Dart SDK refresh scripts.
+
+The iOS App Store candidate route is the encrypted Dart bytecode interpreter
+path, not native AOT patch loading. Real-device testing on June 25, 2026 showed
+the patched iPad app displaying `license:pro` without enabling
+`DART_DYNAMIC_MODULES`. The macOS native-AOT desktop route was also verified
+locally the same day by launching a saved free app with a pro Flutter snapshot
+seeded as patch `1`; the patched app reported `license:pro`.
+CI builds Linux, Android, and macOS engine artifacts with the native AOT patch
+runtime enabled and the interpreter route disabled; iOS is the only App
+Store-safe interpreter patch artifact path.
+Android release APK builds pass locally with the custom Android engine; use
+`scripts/android_runtime_patch_smoke.sh` on a machine with an attached Android
+device or emulator to run the seeded runtime patch proof. Use
+`scripts/linux_runtime_patch_smoke.sh` on a Linux desktop runner to exercise the
+same saved-free-app/pro-patch flow for the Linux embedder.
+
 ## Local Test Fixture
 
 `testapps/license_flavor_patch_test` is kept in the root repository because it
@@ -49,6 +140,8 @@ Generated build output under that app is ignored by this meta-repository.
 
 ## Documents
 
+- `docs/CI.md` describes the GitHub Actions jobs for source checks, CLI/server
+  artifacts, manual custom SDK/engine builds, and opt-in runtime smokes.
 - `docs/REPOSITORIES.md` records the remote URL inventory and cleanup policy.
 - `docs/PLATFORM_TESTING.md` documents the Linux, macOS, and later iOS test
   flow.

docs/CI.md

@@ -0,0 +1,457 @@
+# GitHub CI
+
+The root workflow at `.github/workflows/open-shorebird-ci.yml` validates the
+combined open Shorebird workspace rather than any single submodule in isolation.
+
+## Default CI
+
+Push and pull request runs perform source-level checks and build distributable
+binaries:
+
+1. `source-checks` runs the bootstrap test path with `SKIP_GCLIENT_SYNC=1`,
+   including CLI, code push client, artifact proxy, updater library, open patch
+   tooling, and server tests.
+   This checks the Shorebird CLI focused tests, code push client open-server
+   default tests, open patch tools, server tests, and the root shell scripts
+   without downloading the full engine dependency graph. It also runs
+   `scripts/verify_ci_workflow.sh`, which parses the
+   workflow YAML, checks every workflow `run:` block with `bash -n`, and
+   verifies the expected open SDK/CLI/server artifact contract, including
+   archive creation and checksum sidecar generation. It also checks
+   `.gitmodules`, `docs/REPOSITORIES.md`, and generated `.gclient` files so a
+   fresh GitHub checkout uses open HTTPS remotes instead of local paths, SSH
+   remotes, or official closed Shorebird repositories. The verifier also scans
+   runtime/build-sensitive CLI, updater, artifact-proxy, Flutter tool, Gradle,
+   engine metadata, and web UI artifact-copy sources to reject hosted Shorebird
+   endpoints and official `shorebirdtech` GitHub dependencies. It also reads
+   the forked engine BUILD files and checks that the GN targets and archive
+   names referenced by the manual engine jobs still exist.
+   Before uploading the workspace, run `scripts/verify_upload_readiness.sh`.
+   It invokes the same workflow contract verifier in upload-ready mode, which
+   requires every listed CI support file to be tracked in its owning checkout
+   and requires the root plus required submodule checkouts to be clean.
+   `scripts/verify_sync_open_sources.sh` also exercises the source-link helper
+   in an isolated temporary workspace so clean generated engine checkouts are
+   replaced by the workspace Dart/updater submodules and dirty targets are not
+   overwritten.
+   `scripts/verify_open_infrastructure_defaults.sh` independently scans
+   build-sensitive Flutter, Shorebird CLI, artifact-proxy, updater, `.gclient`,
+   and submodule metadata for closed Shorebird endpoints, official
+   `shorebirdtech` dependency remotes, and private prebuilt buckets, while
+   requiring the open local server and artifact mirror defaults.
+   `scripts/verify_powershell_open_defaults.sh` checks the Windows launcher and
+   Flutter Dart SDK updater PowerShell scripts for open Flutter/artifact
+   defaults and parses them with `pwsh` when it is available.
+   `scripts/verify_write_sha256.sh` smoke-tests the portable checksum helper
+   used by every artifact job.
+   `scripts/verify_ios_interpreter_route_validator.sh` smoke-tests the iOS
+   App Store route gate with synthetic GN args and encrypted patch artifacts,
+   covering a valid interpreter artifact and rejecting dynamic-module,
+   non-iOS, malformed JSON, and Mach-O native patch inputs.
+2. All artifact and runtime-smoke jobs declare `needs: source-checks`, so no
+   uploaded CLI, server, SDK, or engine artifact is produced before the
+   source-level open-replacement contract passes.
+3. `cli-artifacts` compiles:
+   - `shorebird` for Linux x64, macOS x64, macOS arm64, and Windows x64
+   - `open_aot_patch_tools` for Linux x64, macOS x64, macOS arm64, and
+     Windows x64
+   - `artifact_proxy` for Linux x64, macOS x64, macOS arm64, and Windows x64
+   - public updater `patch` binaries packaged as CLI-cache mirror artifacts:
+     `patch-linux-x64.zip`, `patch-darwin-x64.zip`,
+     `patch-darwin-arm64.zip`, and `patch-windows-x64.zip`
+   - `mirror-metadata`, containing
+     `shorebird/<engine-revision>/artifacts_manifest.yaml`
+   The job provisions stable Rust before building the updater `patch` binary,
+   so those mirror artifacts do not depend on preinstalled runner state.
+   CI opens each generated patch mirror ZIP before upload and verifies it has
+   exactly the cache-facing entry name (`patch` on Unix, `patch.exe` on
+   Windows) with a non-empty payload.
+   Each CLI upload is an `open-shorebird-cli-<os>-<arch>.tar.gz` archive with
+   `bin/shorebird`, `bin/open_aot_patch_tools`, `bin/artifact_proxy`,
+   `bin/internal` version metadata, `manifest.json`, and a `.sha256` sidecar.
+   The manifest records the Flutter revision and engine revision used by the
+   bundled CLI cache metadata. The macOS CLI split is intentional: macOS x64
+   runs on `macos-15-intel`, and macOS arm64 runs on `macos-14`. Before upload,
+   CI extracts the archive and runs `shorebird --version`,
+   `open_aot_patch_tools --help`, and `artifact_proxy --health-check` from the
+   extracted layout. The `shorebird --version` smoke must report the open
+   `https://git.tonycloud.org/flutter/shorebird.git` fork and rejects the old
+   official Shorebird SSH remote.
+4. `server-artifacts` runs `go test ./...` and cross-compiles
+   `shorebird-server` for Linux x64/arm64, macOS x64/arm64, and Windows x64
+   targets. Each uploaded archive contains the server binary, `web/` dashboard
+   assets, `.env.example`, `README.md`, `openapi.yaml`, `manifest.json`, and a
+   `.sha256` sidecar. The manifest records both the root workflow commit and
+   the server submodule commit. Keep `web/` beside the executable when
+   unpacking; the server looks for dashboard assets relative to its working
+   directory and executable path.
+   The Linux x64 archive is extracted and smoke-tested in CI by starting the
+   packaged binary with SQLite/local storage, checking `/health`, fetching the
+   dashboard HTML from `/`, and verifying `/openapi.yaml`.
+
+The CLI/server artifacts are uploaded from each workflow run. CLI archives are
+intended for installation or release attachments; patch mirror ZIPs are separate
+because the Shorebird CLI cache expects the `patch-*.zip` names and a `patch`
+or `patch.exe` entry inside each ZIP. The patch mirror ZIPs include `.sha256`
+sidecars and can be copied under
+`/shorebird/<engine-revision>/` on the host referenced by
+`SHOREBIRD_ARTIFACT_BASE_URL`. Each `mirror-patch-*.zip` GitHub artifact also
+includes a publish-ready `shorebird/<engine-revision>/patch-*.zip` copy and
+matching `.sha256` sidecar, so mirror publication can copy the `shorebird/`
+subtree directly. The `mirror-metadata` artifact provides the matching
+`artifacts_manifest.yaml` for the artifact proxy.
+Manual engine artifacts also include a `mirror/` subtree whose contents are
+already laid out under `shorebird/flutter_infra_release/...`; copy that subtree
+to the same artifact mirror root to satisfy the generated
+`artifacts_manifest.yaml` overrides.
+On `full_sdk_build=true` runs, `artifact-mirror` downloads the mirror metadata,
+all platform patch ZIPs, and the Linux/Android/web/iOS/macOS engine artifacts,
+then uploads `open-shorebird-artifact-mirror`. It also downloads the CLI,
+server, and custom Dart SDK artifacts and uploads
+`open-shorebird-release-manifest`, a JSON manifest that verifies every archived
+release artifact has a matching checksum sidecar and records its SHA-256 digest,
+size, relative path, downloaded artifact group, file name, and workflow commit.
+Zero-byte release artifacts are rejected even when their sidecars match.
+The manifest job also requires every
+expected CLI, server, custom Dart SDK, engine, patch-tool, metadata, and mirror
+artifact family to be present. The mirror archive is the checked publish-ready
+mirror root for `SHOREBIRD_ARTIFACT_BASE_URL`; the release manifest is the
+provenance index for the full SDK/CLI/server/engine output set.
+The artifact-mirror job validates the generated manifest with
+`scripts/validate_release_manifest.py` before upload. After downloading workflow
+artifacts, the same validator can audit the manifest against the downloaded
+artifact directory and will reject missing files, duplicate or unsafe paths,
+checksum/size mismatches, sidecar mismatches, orphan sidecars, mismatched
+artifact group or file-name provenance fields, and artifacts that are present on
+disk but missing from the manifest.
+Use the wrapper below after downloading a completed `full_sdk_build=true` run:
+
+```sh
+gh run download <run-id> --dir downloaded-artifacts
+./scripts/verify_downloaded_release_artifacts.sh \
+  --github-sha <run-head-sha> \
+  downloaded-artifacts
+```
+
+It verifies the release manifest sidecar, validates the manifest against every
+downloaded artifact, optionally requires the manifest commit to match the
+expected run SHA, verifies the mirror archive sidecar, safely extracts
+`open-shorebird-artifact-mirror.tar.gz` after rejecting unsafe archive members,
+and validates the extracted mirror root before anything is published.
+
+After the workspace is uploaded to GitHub, the end-to-end proof can be driven
+from a local checkout with:
+
+```sh
+./scripts/verify_hosted_full_sdk_build.sh \
+  --repo owner/repo \
+  --ref main
+```
+
+That helper dispatches `open-shorebird-ci.yml` with `full_sdk_build=true`,
+waits for the hosted workflow run to succeed, downloads all artifacts, and runs
+`scripts/verify_downloaded_release_artifacts.sh` against the downloaded output
+with the workflow run's `headSha`.
+It uses GitHub CLI when `gh` is installed; otherwise it uses the GitHub REST API
+with `GITHUB_TOKEN` or `GH_TOKEN` plus `curl`, `jq`, and `unzip`.
+Use `--linux-heavy-runner`, `--macos-heavy-runner`, and the disk-threshold flags
+when the repository uses custom larger/self-hosted runner labels.
+For local release assembly or reassembly after downloading workflow artifacts,
+run:
+
+```sh
+./scripts/assemble_artifact_mirror.sh downloaded-artifacts public-mirror
+```
+
+The assembler scans direct artifact contents plus `*.tar.gz` engine archives,
+validates archive member paths, rejects links/devices before extraction, copies
+every `shorebird/` mirror subtree into `public-mirror`, rejects conflicting
+files with different bytes, validates that each
+`artifacts_manifest.yaml` override resolves to a copied non-empty file, verifies
+every platform `patch-*.zip` contains exactly the cache-facing `patch` or
+`patch.exe` entry, and writes missing `.sha256` sidecars.
+`scripts/validate_artifact_mirror.py public-mirror` can be run independently
+after safely extracting `open-shorebird-artifact-mirror.tar.gz`; the
+`artifact-mirror` job safe-extracts and validates the assembled archive before
+upload.
+`scripts/verify_assemble_artifact_mirror.sh` keeps the low-level assembler
+covered in default source checks. `scripts/verify_artifact_mirror_workflow_assembly.sh`
+also dry-runs the full `artifact-mirror` aggregation flow with fake downloaded
+artifacts, including the mirror-only input subset, extracted mirror validation,
+and release manifest requirements. This catches path-layout regressions before
+the hosted `full_sdk_build=true` run.
+CI writes checksum sidecars through `scripts/write_sha256.sh` so the artifact
+jobs do not depend on platform-specific checksum tools.
+The workflow defaults all `run` steps to Bash, including Windows matrix jobs,
+because the workspace scripts and packaging commands use Bash syntax.
+
+On June 25, 2026, the Darwin arm64 CLI artifact path was smoke-tested locally:
+the workflow-equivalent commands compiled `shorebird`, `open_aot_patch_tools`,
+and `artifact_proxy`; built the Rust updater `patch` binary; produced
+`open-shorebird-cli-macos-arm64.tar.gz` and `patch-darwin-arm64.zip`; wrote both
+checksum sidecars; extracted the CLI archive; and verified the compiled tools
+could run from the extracted layout.
+The patch mirror ZIP contained a single `patch` entry, matching the CLI cache
+contract.
+
+The Darwin arm64 server artifact path was smoke-tested locally the same day:
+the workflow-equivalent packaging command produced
+`shorebird-server-darwin-arm64.tar.gz`, wrote a `.sha256` sidecar, extracted
+the archive, started the packaged server with SQLite and local storage, and
+verified `/health` returned `status=ok` while `/` served the packaged dashboard
+HTML from the sibling `web/` directory. The packaged server also serves the
+checked OpenAPI contract at `/openapi.yaml`.
+
+## Open Artifact Hosts
+
+The CLI can be used with a self-hosted server and open artifact mirror without
+changing source code. When no project `base_url`, user config, or environment
+override is present, the open CLI defaults API/auth traffic to the local
+self-hosted server at `http://localhost:8080` instead of Shorebird's hosted
+service:
+
+```sh
+export SHOREBIRD_HOSTED_URL=https://updates.example.com
+export SHOREBIRD_ARTIFACT_BASE_URL=https://artifacts.example.com/open
+export SHOREBIRD_FLUTTER_STORAGE_BASE_URL=https://artifacts.example.com/flutter
+export SHOREBIRD_FLUTTER_GIT_URL=https://github.com/example/open-flutter.git
+```
+
+`SHOREBIRD_HOSTED_URL` points API calls at the self-hosted server and is also
+written into new `shorebird.yaml` files as `base_url`. The bundled updater
+library also defaults to `http://localhost:8080` when a legacy app omits
+`base_url`. The self-hosted server publishes its checked OpenAPI contract at
+`http://localhost:8080/openapi.yaml`. The artifact mirror keeps the same path
+layout as Shorebird's default storage bucket:
+
+```text
+$SHOREBIRD_ARTIFACT_BASE_URL/shorebird/<engine-revision>/patch-linux-x64.zip
+$SHOREBIRD_ARTIFACT_BASE_URL/shorebird/<engine-revision>/patch-darwin-x64.zip
+$SHOREBIRD_ARTIFACT_BASE_URL/shorebird/<engine-revision>/patch-darwin-arm64.zip
+$SHOREBIRD_ARTIFACT_BASE_URL/shorebird/<engine-revision>/patch-windows-x64.zip
+$SHOREBIRD_ARTIFACT_BASE_URL/shorebird/<engine-revision>/artifacts_manifest.yaml
+```
+
+When `SHOREBIRD_ARTIFACT_BASE_URL` is not set, the open CLI defaults CLI-managed
+artifact downloads to `http://localhost:8080/artifacts`. Use that local mirror
+root for development, or set `SHOREBIRD_ARTIFACT_BASE_URL` to the public mirror
+where the CI-produced `patch-*.zip` artifacts are hosted.
+
+If the mirror is a bucket-style host, `SHOREBIRD_STORAGE_BASE_URL` and
+`SHOREBIRD_STORAGE_BUCKET` can be used instead of
+`SHOREBIRD_ARTIFACT_BASE_URL`. `SHOREBIRD_FLUTTER_STORAGE_BASE_URL` controls the
+`FLUTTER_STORAGE_BASE_URL` passed to vended Flutter commands; when unset it
+defaults to `http://localhost:8080/download.flutter.io`.
+`SHOREBIRD_FLUTTER_GIT_URL` controls where the CLI clones vended Flutter
+revisions during cache installation. When unset, the open CLI defaults to this
+workspace's open Flutter fork instead of `github.com/shorebirdtech/flutter.git`.
+The Flutter fork also defaults its own engine downloads, Dart SDK refresh
+scripts, doctor network check, Android Gradle Maven host, Android host-app
+integration fixtures, docs artifact scripts, and Shorebird integration tests to
+`http://localhost:8080/download.flutter.io` when `FLUTTER_STORAGE_BASE_URL` is
+unset, so direct Flutter use does not fall back to Shorebird's closed artifact
+host.
+
+The open CI currently does not publish `aot-tools.dill`. That file is a
+different Shorebird linker artifact used by the legacy native-AOT iOS linker
+path. The open App Store-safe iOS path uses encrypted Dart bytecode interpreter
+artifacts instead, and Android/Linux/macOS/Windows patch creation uses the
+public updater `patch` binaries above.
+The CLI cache does not download `aot-tools.dill` by default. Set
+`SHOREBIRD_ENABLE_LEGACY_AOT_TOOLS=1` only when deliberately validating the
+development-only legacy native-AOT linker path.
+
+Runtime smoke scripts that need external targets are kept out of default CI:
+`scripts/android_runtime_patch_smoke.sh` requires an attached Android
+device/emulator with app-private storage access, and
+`scripts/linux_runtime_patch_smoke.sh` requires a Linux desktop runtime or
+`xvfb-run`. Use them on suitable self-hosted runners when extending runtime
+coverage beyond the artifact build matrix.
+
+Use `workflow_dispatch` with `run_runtime_smokes=true` to run those external
+runtime smokes from CI. The runtime jobs are intentionally separate from
+`full_sdk_build=true`: they are for provisioned runners that already have the
+matching local engine build outputs in the checkout workspace. Runtime checkout
+uses `clean: false` so self-hosted runners can preserve those `out/` directories
+between preparation and smoke runs.
+
+| Input | Default | Used by |
+| --- | --- | --- |
+| `run_runtime_smokes` | `false` | Enables `linux-runtime-smoke` and `android-runtime-smoke` |
+| `linux_runtime_runner` | `self-hosted` | Runner label for `scripts/linux_runtime_patch_smoke.sh` |
+| `android_runtime_runner` | `self-hosted` | Runner label for `scripts/android_runtime_patch_smoke.sh` |
+| `android_serial` | empty | Optional `adb` serial passed as `ANDROID_SERIAL` |
+
+The Linux runtime runner must provide
+`flutter/engine/src/out/linux_release_x64`. The Android runtime runner must provide
+`flutter/engine/src/out/android_release_arm64` and
+`flutter/engine/src/out/host_release_arm64`, plus an Android target where either
+`adb shell run-as` works for the test package or `adb root` works. It must also
+provide Java on `PATH` because the smoke builds APKs before seeding the patch.
+
+## Heavy SDK Builds
+
+Default push and pull request runs build the custom SDK and engine artifacts.
+Manual `workflow_dispatch` runs also build them by default because
+`full_sdk_build=true` is the default input value; set `full_sdk_build=false`
+only for source/CLI/server-only manual runs.
+
+The heavy jobs install Chromium's `depot_tools` into the workflow workspace
+before running `gclient`, so they can bootstrap from a clean runner. The
+workflow defaults heavy jobs to managed GitHub-hosted runners:
+
+- `ubuntu-latest` for Linux SDK, Linux engine, Android engine, and web SDK
+  builds
+- `macos-latest` for macOS Dart SDK, iOS engine, and macOS engine builds
+
+Override `linux_heavy_runner` / `macos_heavy_runner` when a repository wants
+larger or self-hosted runners. Every SDK/engine job also runs
+`scripts/check_ci_capacity.sh` before `gclient sync` or `ninja`; SDK-only jobs
+and engine jobs require at least 8 GiB free by default. Raise the dispatch
+thresholds for runner images where a larger preflight budget should be enforced.
+The hosted Android engine job also provisions Temurin Java 17 before building
+Android JAR/APK-related engine artifacts. Every SDK/engine job verifies
+`python3`, `gclient`, and `ninja` before generating build files, so
+PATH/toolchain problems fail before a long build starts. CI sets
+`DEPOT_TOOLS_UPDATE=0`, and the local bootstrap scripts default the same way,
+so depot_tools uses the pinned submodule revision unless explicitly overridden.
+
+Manual dispatch accepts these workflow inputs:
+
+| Input | Default | Used by |
+| --- | --- | --- |
+| `linux_heavy_runner` | `ubuntu-latest` | `custom-dart-sdk`, `linux-engine`, `android-engine`, `web-sdk` |
+| `macos_heavy_runner` | `macos-latest` | `custom-dart-sdk-macos`, `ios-engine` / Apple engine artifacts |
+| `sdk_min_free_disk_gb` | `8` | Minimum free disk GiB for `custom-dart-sdk` and `custom-dart-sdk-macos` |
+| `engine_min_free_disk_gb` | `8` | Minimum free disk GiB for Linux, Android, web, iOS, and macOS engine builds |
+| `base_flutter_engine_revision` | empty | Optional upstream Flutter engine revision recorded in `artifacts_manifest.yaml` for non-overridden artifact proxy fallbacks |
+
+Use these inputs to move the SDK/engine jobs onto different larger or
+self-hosted runners without editing the workflow file. The Linux heavy jobs also run
+`scripts/free_ci_disk_linux.sh`, which removes unrelated preinstalled toolchain
+caches only when `GITHUB_ACTIONS=true` and `RUNNER_ENVIRONMENT=github-hosted`.
+Self-hosted runners skip that cleanup by default. Set `CI_FREE_DISK_SPACE=0` to
+skip cleanup anywhere, or `CI_FREE_DISK_SPACE_FORCE=1` to opt in on a
+self-hosted runner.
+When `base_flutter_engine_revision` is empty, `mirror-metadata` records the
+same revision as `flutter/bin/internal/engine.version`. Set it when the open
+Shorebird engine revision is a custom fork revision and unchanged artifacts
+should be proxied back to a different upstream Flutter engine revision.
+
+The engine jobs perform two syncs when `run_gclient_sync=true`: the root
+workspace sync for the Dart SDK checkout, then a second sync from `flutter/` for
+Flutter engine dependencies written by `scripts/write_gclient.sh`. Linux engine
+jobs use `INCLUDE_ENGINE_DEPS=1` to include Flutter engine dependencies,
+Android dependencies, and emsdk; the Apple engine job uses the same flag to
+include iOS, Android, and emsdk
+dependencies on macOS.
+Before building, `scripts/sync_open_sources.sh` links
+`flutter/engine/src/flutter/third_party/dart` to the `dart-sdk` submodule
+and `flutter/engine/src/flutter/third_party/updater` to the `updater`
+submodule. It does not clone the official `shorebirdtech/updater` repository by
+default; set `UPDATER_URL` explicitly only when testing a different updater
+fork. The helper rejects known unpatched upstream Dart SDK remotes and official
+Shorebird updater remotes so CI does not accidentally build from the wrong
+component checkout.
+The Flutter fork's `DEPS` file also points its Dart SDK and updater dependency
+URLs at the open mirrors and does not reference Shorebird's private
+`shorebird-dart-sdk-prebuilt` bucket; custom SDK jobs build and archive the
+open Dart SDK fork directly.
+
+`custom-dart-sdk` and `custom-dart-sdk-macos` build the Dart SDK fork with:
+
+```gn
+dart_dynamic_modules = false
+dart_enable_aot_patching = true
+dart_enable_shorebird_interpreter = true
+```
+
+They run `scripts/verify_dart_sdk_args.sh`, then the focused VM patch API
+tests. The Linux job uploads `custom-dart-sdk-linux-x64`; the macOS job uploads
+`custom-dart-sdk-macos-arm64`. Each archive contains the Dart SDK,
+`gen_snapshot`, `dartaotruntime`, `args.gn`, and a `manifest.json` that records
+the root workflow commit, Dart SDK source commit, and patch-related build
+flags. The workflow also uploads `.sha256` sidecars for the SDK archives.
+Before writing the checksum, each SDK job extracts the archive, verifies
+`manifest.json`, `args.gn`, `gen_snapshot`, `dartaotruntime`, and
+`dart-sdk/bin/dart`, then runs the extracted `dart --version`.
+
+`ios-engine` builds:
+
+- `host_release_arm64` with `--shorebird-interpreter`,
+  `dart_dynamic_modules=false`, `dart_enable_aot_patching=true`, and
+  `dart_enable_shorebird_interpreter=true`
+- `ios_release` with `--shorebird-interpreter`
+- `macos_release_arm64` with `dart_dynamic_modules=false`,
+  `dart_enable_aot_patching=true`, `shorebird_enable_aot_patching=true`, and
+  `shorebird_use_interpreter=false`
+
+It runs `scripts/verify_ios_interpreter_route.sh` before uploading the
+`ios-interpreter-engine` artifact, so the archived build proves
+`DART_DYNAMIC_MODULES` is off and the iOS route uses the bytecode interpreter
+instead of native AOT patch loading. The archive includes `Flutter.framework`,
+`Flutter.xcframework`, a mirror-ready `ios-release/artifacts.zip` containing
+the xcframework plus `gen_snapshot_arm64`, `analyze_snapshot_arm64`, and the
+code-sign configuration files Flutter expects, the
+`host_release_arm64/gen_snapshot` binary built with `--shorebird-interpreter`,
+the iOS and host `args.gn` files, and a `manifest.json` that records
+`dart_dynamic_modules=false`,
+`dart_enable_aot_patching=true`, `dart_enable_shorebird_interpreter=true`,
+`shorebird_enable_aot_patching=false`, `shorebird_use_interpreter=true`, and
+the Flutter engine revision; the workflow also uploads a `.sha256` sidecar for
+the engine archive.
+Before checksum upload, CI extracts the iOS engine archive and verifies
+`Flutter.framework`, `Flutter.xcframework`, `ios-release/artifacts.zip`, the
+mirror copy under `mirror/shorebird/flutter_infra_release/flutter/<engine>`,
+both args files, `manifest.json`, and the executable host `gen_snapshot`.
+When an app or IPA is supplied to the gate, strict mode also rejects bundled
+patch payloads, executable-memory entitlements, and raw `aot_patch_key_hex`
+material in `shorebird.yaml`.
+
+The same Apple job uploads a separate `macos-engine-arm64` artifact containing
+`FlutterMacOS.framework.zip`, `flutter_patched_sdk_product.zip`, the macOS
+`args.gn`, a mirror-ready copy of the macOS framework override, a manifest with
+the Flutter engine revision, and a `.sha256` sidecar. The shared
+`flutter_patched_sdk_product.zip` mirror override is published only by the Linux
+engine job to avoid duplicate producers for the same mirror path. The macOS
+build is checked with
+`scripts/verify_engine_args.sh` so CI fails if `dart_dynamic_modules=true`
+appears or if the native AOT patch runtime flags are missing from the generated
+args. CI extracts the macOS engine archive before upload and verifies the
+framework zip, patched SDK zip, args file, manifest, and framework mirror
+subtree.
+
+`linux-engine` builds `linux_release_x64` on Ubuntu with
+`dart_dynamic_modules=false`, `dart_enable_aot_patching=true`,
+`shorebird_enable_aot_patching=true`, and `shorebird_use_interpreter=false`. It
+uploads `linux-x64-flutter-gtk.zip`, `flutter_patched_sdk_product.zip`,
+`artifacts.zip`, mirror-ready copies of those engine override files, `args.gn`,
+a manifest with the Flutter engine revision, and a `.sha256` sidecar. CI
+extracts the archive before upload and verifies the GTK zip, patched SDK zip,
+artifacts zip, args file, manifest, and mirror subtree.
+
+`android-engine` builds `android_release_arm64` on Ubuntu with
+`dart_dynamic_modules=false`, `dart_enable_aot_patching=true`,
+`shorebird_enable_aot_patching=true`, and `shorebird_use_interpreter=false`. It
+uploads `artifacts.zip`, `symbols.zip`, `flutter.jar`, `libflutter.so`, host
+`gen_snapshot_arm64`, `analyze_snapshot_arm64`, mirror-ready copies of the
+Android engine override files, `args.gn`, a manifest with the Flutter engine
+revision, and a `.sha256` sidecar. CI extracts the archive before upload and
+verifies the Android artifacts/symbols zips, `flutter.jar`, `libflutter.so`,
+host snapshot/analyzer tools, args file, manifest, and mirror subtree.
+
+`web-sdk` builds the Flutter web SDK archive from `wasm_release` with
+`dart_dynamic_modules=false` and `flutter_prebuilt_dart_sdk=true`, then uploads
+`flutter-web-sdk.zip`, a mirror-ready copy of that SDK archive, `args.gn`, a
+manifest with the Flutter engine revision, and a `.sha256` sidecar. The web job
+does not download Flutter's private prebuilt Dart SDK; it links
+`dart-sdk/tools/sdks/dart-sdk` into Flutter's expected prebuilt path before
+running GN. Native engine jobs use `--no-prebuilt-dart-sdk` because the open
+workspace builds those SDK artifacts from the linked Dart checkout instead. Web
+is still not a Shorebird CodePush release platform in this CLI/protocol; this
+job exists to keep the open Flutter SDK/web artifacts buildable from the
+workspace. CI extracts the web SDK archive before upload and verifies the SDK
+zip, args file, manifest, and mirror subtree.
+
+Set `run_gclient_sync=false` only for debugging a runner image that already has
+all gclient-managed dependencies restored.

docs/PLATFORM_TESTING.md

@@ -1,4 +1,4 @@
-# Linux, macOS, and iOS Platform Testing
+# Platform Testing
 
 The first complete runtime proof was built on Windows. The next platform pass
 should verify the same source layout on Linux and macOS, then use macOS to
@@ -14,6 +14,9 @@ Linux:
 - Dart or Flutter on `PATH`
 - Go 1.23+
 - Python and standard build dependencies required by Dart/Flutter
+- Flutter Linux desktop build dependencies (`clang`, `cmake`, `ninja`,
+  `pkg-config`, GTK development headers)
+- A graphical session or `xvfb-run` for headless runtime smoke tests
 
 macOS:
 
@@ -24,6 +27,16 @@ macOS:
 - Xcode command line tools
 - Full Xcode for iOS simulator/device follow-up
 
+Android runtime validation:
+
+- Android SDK platform tools (`adb`)
+- Java/JDK on `PATH` for APK builds
+- A connected Android device or emulator
+- Either `adb shell run-as` access for the test package or a rooted
+  emulator/device. The seeded runtime smoke writes directly to the test app's
+  private updater directory; production installs normally receive patches from
+  the updater download flow.
+
 Both platforms need network access for a fresh `git submodule update` and
 `gclient sync`.
 
@@ -59,6 +72,11 @@ Useful environment variables:
 | `IOS_IPA=/path/to/App.ipa` | Optionally verify the `Payload/*.app` inside an IPA instead of a raw app bundle. |
 | `IOS_PATCH_ARTIFACT=/path/to/dlc.vmcode` | Optionally verify that the patch artifact is an encrypted iOS arm64 interpreter full-snapshot artifact. |
 | `APP_STORE_STRICT=1` | Fail the iOS route check when App Store-inappropriate signing state, such as `get-task-allow=true`, is present. |
+| `ANDROID_SERIAL=<serial>` | Select the Android device used by `scripts/android_runtime_patch_smoke.sh` when more than one device is attached. |
+| `SKIP_ANDROID_BUILDS=1` | Reuse APKs for the Android runtime smoke instead of rebuilding; set `ANDROID_FREE_APK` and `ANDROID_PRO_APK`. |
+| `KEEP_ANDROID_RUNTIME_SMOKE_ARTIFACTS=1` | Keep the temporary APK/libapp extraction directory after the Android runtime smoke. |
+| `LINUX_RUNTIME_SMOKE_XVFB=0` | Disable automatic `xvfb-run` wrapping in `scripts/linux_runtime_patch_smoke.sh`. |
+| `KEEP_LINUX_RUNTIME_SMOKE_ARTIFACTS=1` | Keep the temporary Linux app copy and free/pro bundles after the Linux runtime smoke. |
 
 ## Expected Checks
 
@@ -73,15 +91,196 @@ The bootstrap scripts run:
 7. self-hosted server Go tests
 8. license/flavor AOT verification when an AOT patch SDK build already exists.
    The verifier checks `AOT_PATCH_BUILD_DIR` first, then common local outputs
-   such as `dart-sdk-new/xcodebuild/ReleaseARM64`,
+   such as `dart-sdk/xcodebuild/ReleaseARM64`,
-   `dart-sdk-new/out/ReleaseARM64AotPatch`, and
+   `dart-sdk/out/ReleaseARM64AotPatch`, and
-   `dart-sdk-new/out/ReleaseX64AotPatch`.
+   `dart-sdk/out/ReleaseX64AotPatch`.
 9. iOS interpreter route verification when local `ios_release` and
    `host_release_arm64` engine args exist. This checks that
    `DART_DYNAMIC_MODULES` is off, the no-DDM interpreter route is on for both
    the device engine and host snapshotter, and the native AOT patch path is off
    for iOS.
 
+## Current Coverage Status
+
+| Platform | Open patch route | Current status |
+| --- | --- | --- |
+| iOS | Encrypted Dart bytecode interpreter artifact, `DART_DYNAMIC_MODULES=false` | Verified on a real iPad on June 25, 2026; the patched app displayed `license:pro`. |
+| Android | Public updater binary diff `patch-*.zip` artifact with native AOT patch runtime enabled | CI builds mirror-ready patch binaries and a manual `android-engine-arm64` artifact with `dart_enable_aot_patching=true`, `shorebird_enable_aot_patching=true`, and interpreter mode off; local arm64 release APK build passed. Runtime smoke script is available, but this macOS host currently has no Android device or AVD attached. |
+| macOS | Public updater binary diff `patch-*.zip` artifact with native AOT patch runtime enabled | Verified locally on June 25, 2026 with a native-AOT Flutter snapshot patch; the patched app displayed `license:pro`. CI builds macOS x64/arm64 patch binaries and a manual `macos-engine-arm64` artifact with native AOT patch runtime args verified. |
+| Linux | Public updater binary diff `patch-*.zip` artifact with native AOT patch runtime enabled | CI builds the Linux x64 patch binary and a manual `linux-engine-x64` artifact with native AOT patch runtime args verified. The runtime smoke defaults to `linux_release_x64`; local runtime validation requires a Linux runner. |
+| Windows | Public updater binary diff `patch-*.zip` artifact | Previously tested; CI still builds the Windows patch binary. |
+| Web | Not a Shorebird CodePush release platform in this CLI/protocol | Manual CI builds `flutter-web-sdk`; local release web build passed with the matching local engine, but it is not counted as a Shorebird runtime patch test. |
+
+The open CI currently does not publish `aot-tools.dill`. That artifact belongs
+to the legacy native-AOT iOS linker path. The App Store-safe iOS route proven
+above does not use it; Android/Linux/macOS/Windows patch creation uses the
+public updater `patch` binary instead.
+
+## macOS Host Smoke Results
+
+On June 25, 2026, the default source-level bootstrap path passed locally with
+`SKIP_GCLIENT_SYNC=1`, the workspace Flutter/Dart SDK, and network access for
+pub packages:
+
+```sh
+SKIP_GCLIENT_SYNC=1 \
+DART_BIN=/Users/tonylu/git/shorebird-workspace/flutter/bin/dart \
+FLUTTER_BIN=/Users/tonylu/git/shorebird-workspace/flutter/bin/flutter \
+  ./scripts/bootstrap_linux.sh
+```
+
+This ran the focused Shorebird CLI tests, open patch tool tests, self-hosted
+server Go tests, and license/flavor AOT verifier. The AOT verifier reported:
+
+```text
+AOT patch applied to license_flavor_patch_test successfully.
+base: license:free / pro-feature:off
+patch: license:pro / pro-feature:enabled
+```
+
+The same app also built successfully for macOS release with the local engine:
+
+```sh
+flutter build macos --release \
+  --local-engine-src-path=/Users/tonylu/git/shorebird-workspace/flutter/engine/src \
+  --local-engine=host_release_arm64 \
+  --local-engine-host=host_release_arm64 \
+  --dart-define=LICENSE_TYPE=free
+```
+
+Output:
+
+```text
+build/macos/Build/Products/Release/license_flavor_patch_test.app
+```
+
+On June 25, 2026, the macOS runtime patch path was also verified locally. The
+test saved a free baseline app, rebuilt the same Flutter app with
+`--dart-define=LICENSE_TYPE=pro`, copied the resolved pro
+`App.framework/Versions/A/App` Mach-O into the sandboxed updater container as:
+
+```text
+Library/Application Support/shorebird/shorebird_updater/
+  license-flavor-patch-test/patches/1/dlc.vmcode
+```
+
+and seeded `pointers.json` plus `patches/1/state.json` for patch `1`.
+Launching the saved free app selected that patch path and wrote:
+
+```text
+license:pro
+pro-feature:enabled
+```
+
+The seeded payload must be a Flutter app snapshot for this smoke. A standalone
+Dart verifier snapshot is loadable by the updater handoff, but it is not a
+valid Flutter application isolate and fails later with `dart:ui` missing.
+When copying from `App.framework/App`, resolve the framework symlink first
+(`Versions/A/App` or `cp -L`) so the updater validates the real Mach-O size
+rather than the symlink size.
+
+Android arm64 release also built successfully with the local Android engine:
+
+```sh
+flutter build apk --release \
+  --target-platform android-arm64 \
+  --local-engine-src-path=/Users/tonylu/git/shorebird-workspace/flutter/engine/src \
+  --local-engine=android_release_arm64 \
+  --local-engine-host=host_release_arm64 \
+  --dart-define=LICENSE_TYPE=free
+```
+
+Output:
+
+```text
+build/app/outputs/flutter-apk/app-release.apk
+```
+
+Android runtime validation is scripted but was not run to completion on this
+macOS host because `adb devices -l` returned no Android devices and
+`emulator -list-avds` returned no AVDs. When a target is available, run:
+
+```sh
+ANDROID_SERIAL=<device-or-emulator-serial> \
+  ./scripts/android_runtime_patch_smoke.sh
+```
+
+The same script can be run from GitHub Actions with `workflow_dispatch` and
+`run_runtime_smokes=true` on a provisioned Android runner. Use
+`android_runtime_runner` to choose the runner label and `android_serial` to
+select the target device when needed.
+
+The script builds free and pro arm64 release APKs with the local Android
+engine, installs the free APK, verifies the visible `license:free` and
+`pro-feature:off` UI with `uiautomator`, extracts the pro `libapp.so`, seeds it
+as patch `1` under the app-private `files/shorebird_updater` directory,
+relaunches the free app, and verifies `license:pro` plus
+`pro-feature:enabled`.
+
+The seed step needs access to app-private storage. Use an emulator/device where
+`adb shell run-as com.example.licenseflavorpatchtest.license_flavor_patch_test`
+works, or a rooted emulator/device where `adb root` works. This seeded smoke is
+for local runtime proof; production Android patch installation should exercise
+the updater download path through the self-hosted server.
+
+A normal web release build succeeds when pointed at the matching local engine:
+
+```sh
+flutter build web --release \
+  --local-engine-src-path=/Users/tonylu/git/shorebird-workspace/flutter/engine/src \
+  --local-engine=host_release_arm64 \
+  --local-engine-host=host_release_arm64 \
+  --dart-define=LICENSE_TYPE=free
+```
+
+Output:
+
+```text
+build/web/main.dart.js
+```
+
+Running the same web build without `--local-engine` currently fails because the
+prebuilt `const_finder.dart.snapshot` in `flutter/bin/cache` expects a different
+kernel binary format than this workspace Dart SDK emits. Use the local engine
+when validating this workspace's web build artifacts.
+
+The self-hosted server bundle packaging was also smoke-tested locally for
+`darwin/arm64`: the archive was extracted, the server started with SQLite and
+local storage, `/health` returned `status=ok`, and `/` served the packaged
+dashboard HTML from the sibling `web/` directory. The server serves the checked
+OpenAPI contract at `/openapi.yaml`, and CI verifies that endpoint from the
+packaged Linux x64 archive. CI server artifacts therefore package `web/` and
+`openapi.yaml` next to the binary instead of uploading a bare executable.
+
+## Linux Runtime Smoke
+
+Linux runtime validation is scripted for a Linux host:
+
+```sh
+./scripts/linux_runtime_patch_smoke.sh
+```
+
+The script copies `testapps/license_flavor_patch_test` into a temporary
+directory, generates the missing Linux platform scaffold there with
+`flutter create --platforms=linux`, builds free and pro release bundles with the
+local Linux engine, launches the saved free bundle, verifies
+`license:free`/`pro-feature:off`, seeds the pro bundle's `lib/libapp.so` as
+patch `1` under:
+
+```text
+~/.shorebird_cache/shorebird_updater/license-flavor-patch-test/
+```
+
+then relaunches the saved free bundle and verifies `license:pro` plus
+`pro-feature:enabled`. If no `DISPLAY` is set and `xvfb-run` exists, the script
+uses it automatically.
+
+This macOS host cannot execute Linux desktop bundles, so this check remains a
+Linux-runner task. The same check can be triggered in GitHub Actions with
+`workflow_dispatch` and `run_runtime_smokes=true` on a provisioned Linux
+runner. Use `linux_runtime_runner` to choose the runner label; the runner must
+preserve the matching `flutter/engine/src/out/host_release` local engine output.
+
 ## iOS Preparation Notes
 
 The macOS script writes this minimal root `.gclient` by default:
@@ -127,8 +326,14 @@ request JIT or unsigned-executable-memory entitlements, and should not have
 `get-task-allow=true` in strict mode. When `IOS_PATCH_ARTIFACT` is set, the gate
 also rejects Mach-O and ELF patch files and requires the encrypted open artifact
 metadata to declare `runtime_mode=dart-bytecode-interpreter`, `target_os=ios`,
-`target_arch=arm64`, and `payload_kind=full-snapshot`. Real patches should
+`target_arch=arm64`, and `payload_kind=full-snapshot`. It parses the artifact
-arrive through the updater after the reviewed app is installed.
+as JSON and also requires the AES-256-GCM wrapper fields, base64 ciphertext,
+nonce/tag, key id, payload digest, and AAD digest to be present and well
+formed. In strict mode, the gate also rejects bundled `aot_patch_key_hex`
+values; production apps should provide patch keys with
+`FlutterDartProject.shorebirdAotPatchKeyProvider` or an equivalent app-owned
+key source. Real patches should arrive through the updater after the reviewed
+app is installed.
 
 ## iOS Device Results
 
@@ -177,12 +382,14 @@ path when it is used to produce iOS AOT snapshots:
 
 ```sh
 flutter/tools/gn --runtime-mode=release --mac-cpu=arm64 \
-  --target-dir=host_release_arm64 --shorebird-interpreter
+  --target-dir=host_release_arm64 --shorebird-interpreter \
+  --gn-args='dart_dynamic_modules=false dart_enable_aot_patching=true dart_enable_shorebird_interpreter=true shorebird_use_interpreter=true'
 ninja -C out/host_release_arm64 gen_snapshot
 ```
 
-Without the host-side interpreter flag, the generated app snapshot can bind AOT
+Without the host-side interpreter and AOT patch flags, the generated app
-static calls directly to base `Code` objects and omit the static-call metadata
+snapshot can bind AOT static calls directly to base `Code` objects and omit the
+static-call metadata
 that the iOS interpreter runtime uses to enter patched bytecode.
 
 The current open-source interpreter path wires the no-DDM artifact handoff and
@@ -190,8 +397,10 @@ an initial product-AOT function replacement mapper. Interpreter-mode artifacts
 now force and validate `payload_kind=full-snapshot`; compact interpreter diffs
 are rejected until runtime reconstruction exists. The engine can hand an
 encrypted open patch artifact to `Dart_InstallAotPatch`, decrypt it with an
-explicit `shorebird.yaml` AES key, verify the decrypted payload is Dart
+app-owned AES key provider, verify the decrypted payload is Dart bytecode, and
-bytecode, and install it through `Dart_ReloadBytecodePatch`.
+install it through `Dart_ReloadBytecodePatch`. A development-only
+`aot_patch_key_hex` field in `shorebird.yaml` is still supported when no app key
+provider is configured, but strict App Store-route checks reject it.
 
 For product iOS AOT, `Dart_ReloadBytecodePatch` no longer uses stock VM reload.
 It reads patch bytecode as data, maps declarations to already-loaded
@@ -255,9 +464,9 @@ IOS_PATCH_ARTIFACT=/private/tmp/shorebird-seed-main/shorebird_updater/patches/1/
 This verified the generated iOS and host engine args, found no bundled
 `shorebird_updater` or `dlc.vmcode` payload in the app bundle, found no JIT or
 unsigned-executable-memory entitlement, confirmed `get-task-allow` is not true,
-and verified that the seeded patch artifact is an encrypted interpreter
+confirmed no `aot_patch_key_hex` is bundled, and verified that the seeded patch
-full-snapshot for iOS arm64. Passing a Mach-O binary as `IOS_PATCH_ARTIFACT`
+artifact is an encrypted interpreter full-snapshot for iOS arm64. Passing a
-correctly fails the route gate.
+Mach-O binary as `IOS_PATCH_ARTIFACT` correctly fails the route gate.
 
 The remaining App Store/TestFlight proof is a distribution test, not a local
 build test:
@@ -284,12 +493,13 @@ must emit an interpreter payload in that compatible shape, and compact
 reconstruction still needs to move into the SDK before compact bytecode patches
 can be accepted.
 
-For development-device encrypted interpreter tests, `shorebird.yaml` may include
+For encrypted interpreter tests, `shorebird.yaml` may include these top-level
-these top-level fields:
+fields:
 
 ```yaml
+aot_patch_runtime_mode: dart-bytecode-interpreter
 aot_patch_key_id: test-key
-aot_patch_key_hex: 000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f
+aot_patch_app_build_id: 1.2.3+4
 aot_patch_base_flavor_id: free
 aot_patch_base_license_type: free
 aot_patch_flavor_id: pro
@@ -298,8 +508,30 @@ aot_patch_sdk_hash: <flutter-engine-or-dart-sdk-hash>
 aot_patch_base_snapshot_hash: <sha256-of-base-bytecode-snapshot>
 ```
 
-The YAML key path is only the first open bridge for local verification. A
+`aot_patch_bytecode_path` is optional and should normally be omitted. When it
-production App Store implementation still needs an app-owned key callback or
+is omitted, `shorebird patch ios` compiles the patch target with the Dart SDK's
-equivalent secure key source, a verified compatible interpreter payload
+`dart2bytecode` snapshot and writes `build/ios_interpreter_patch.bytecode`.
-compiler, compact interpreter reconstruction, and TestFlight/App Store review
+The generated bytecode compile forwards user `--dart-define` values, Flutter's
-validation.
+`FLUTTER_APP_FLAVOR` define, and Flutter's standard version/revision/Dart SDK
+defines from `bin/cache/flutter.version.json`. It also mirrors Flutter's
+runtime feature flag define (`FLUTTER_ENABLED_FEATURE_FLAGS`) for enabled
+runtime-id features.
+Set `aot_patch_bytecode_path` or `SHOREBIRD_IOS_INTERPRETER_PATCH_PATH` only to
+override that generated payload during local experiments.
+
+Development-only local tests may also include `aot_patch_key_hex`, but reviewed
+iOS app bundles should not. The `license_flavor_patch_test` iOS app now provides
+the test AES key through `FlutterDartProject.shorebirdAotPatchKeyProvider`
+instead.
+
+`shorebird patch ios` now treats the interpreter route as the default iOS patch
+artifact path. It packages the generated or overridden Dart bytecode payload as
+an encrypted `open-aot-vmcode-encrypted-v1` full-snapshot artifact with
+`runtime_mode=dart-bytecode-interpreter`, `target_os=ios`, and
+`target_arch=arm64`. For production builds, provide the encryption key to the
+CLI with `SHOREBIRD_AOT_PATCH_KEY_HEX` and keep `aot_patch_key_hex` out of the
+bundled app. The legacy native-AOT iOS patch path is development-only and now
+requires `SHOREBIRD_IOS_NATIVE_AOT_PATCH=1`.
+
+A production App Store implementation still needs compact interpreter
+reconstruction and TestFlight/App Store review validation.

docs/REPOSITORIES.md

@@ -1,17 +1,17 @@
 # Repository Inventory
 
-Last verified: 2026-06-24.
+Last verified: 2026-06-26.
 
 ## Active Top-Level Repositories
 
 | Path | Remote URL | Branch | Pinned commit |
 | --- | --- | --- | --- |
-| `dart-sdk-new` | `https://git.tonycloud.org/dart-lang/sdk.git` | `tonycloud/dev` | `08139af589d0d32fbdec64b127c075ea3427cde8` |
+| `dart-sdk` | `https://github.com/tony-cloud/dart-sdk.git` | `tonycloud/dev` | `57b27a7b44a9112c7cb3a1cb3c73636fc149bd16` |
-| `depot_tools` | `https://chromium.googlesource.com/chromium/tools/depot_tools.git` | `main` | `90f5d4d14de66a5aae4a55b554ad4565111169af` |
+| `depot_tools` | `https://chromium.googlesource.com/chromium/tools/depot_tools.git` | `main` | `226aa79e9947adc1e9e0c79f96b58562516535d9` |
-| `flutter` | `https://git.tonycloud.org/flutter/flutter.git` | `shorebird/dev` | `9754ce03d76fb06c23a72ddbd8b7137bfa85446c` |
+| `flutter` | `https://github.com/tony-cloud/flutter.git` | `tonycloud/dev` | `5b96fd59be2f00061cccaaa23a02e15e720c1161` |
-| `shorebird` | `https://git.tonycloud.org/flutter/shorebird.git` | `main` | `c824005c2dc65f56b0fa078984fadb649876fce7` |
+| `shorebird` | `https://git.tonycloud.org/flutter/shorebird.git` | `main` | `07a654e7717a20d685c3eadf4b55c2e6731e96fa` |
-| `shorebird-server` | `https://git.tonycloud.org/flutter/shorebird-server.git` | `main` | `774954fce70181846995ebcad842e9c54e57f1a2` |
+| `shorebird-server` | `https://git.tonycloud.org/flutter/shorebird-server.git` | `main` | `d6e5a39546905b85e2345b8058c4350ed236184c` |
-| `updater` | `https://git.tonycloud.org/flutter/shorebird-updater.git` | `main` | `3ac748ff28eb4ebb53630c66230b9b1be5df73c2` |
+| `updater` | `https://git.tonycloud.org/flutter/shorebird-updater.git` | `main` | `5d4e9c339636fc2f67cbe9892026d9e10b0888bc` |
 
 ## Submodule Policy
 
@@ -34,43 +34,43 @@ file.
 
 | Path | Remote URL |
 | --- | --- |
-| `dart-sdk-new/buildtools/clang_format/script` | `https://chromium.googlesource.com/chromium/llvm-project/cfe/tools/clang-format.git` |
+| `dart-sdk/buildtools/clang_format/script` | `https://chromium.googlesource.com/chromium/llvm-project/cfe/tools/clang-format.git` |
-| `dart-sdk-new/tests/co19/src` | `https://dart.googlesource.com/co19` |
+| `dart-sdk/tests/co19/src` | `https://dart.googlesource.com/co19` |
-| `dart-sdk-new/third_party/binaryen/src` | `https://chromium.googlesource.com/external/github.com/WebAssembly/binaryen.git` |
+| `dart-sdk/third_party/binaryen/src` | `https://chromium.googlesource.com/external/github.com/WebAssembly/binaryen.git` |
-| `dart-sdk-new/third_party/boringssl/src` | `https://boringssl.googlesource.com/boringssl.git` |
+| `dart-sdk/third_party/boringssl/src` | `https://boringssl.googlesource.com/boringssl.git` |
-| `dart-sdk-new/third_party/cpu_features/src` | `https://chromium.googlesource.com/external/github.com/google/cpu_features.git` |
+| `dart-sdk/third_party/cpu_features/src` | `https://chromium.googlesource.com/external/github.com/google/cpu_features.git` |
-| `dart-sdk-new/third_party/crashpad/crashpad` | `https://chromium.googlesource.com/crashpad/crashpad.git` |
+| `dart-sdk/third_party/crashpad/crashpad` | `https://chromium.googlesource.com/crashpad/crashpad.git` |
-| `dart-sdk-new/third_party/cygwin` | `https://chromium.googlesource.com/chromium/deps/cygwin.git` |
+| `dart-sdk/third_party/cygwin` | `https://chromium.googlesource.com/chromium/deps/cygwin.git` |
-| `dart-sdk-new/third_party/emsdk` | `https://dart.googlesource.com/external/github.com/emscripten-core/emsdk.git` |
+| `dart-sdk/third_party/emsdk` | `https://dart.googlesource.com/external/github.com/emscripten-core/emsdk.git` |
-| `dart-sdk-new/third_party/googletest` | `https://fuchsia.googlesource.com/third_party/googletest` |
+| `dart-sdk/third_party/googletest` | `https://fuchsia.googlesource.com/third_party/googletest` |
-| `dart-sdk-new/third_party/icu` | `https://chromium.googlesource.com/chromium/deps/icu.git` |
+| `dart-sdk/third_party/icu` | `https://chromium.googlesource.com/chromium/deps/icu.git` |
-| `dart-sdk-new/third_party/jinja2` | `https://chromium.googlesource.com/chromium/src/third_party/jinja2.git` |
+| `dart-sdk/third_party/jinja2` | `https://chromium.googlesource.com/chromium/src/third_party/jinja2.git` |
-| `dart-sdk-new/third_party/libc` | `https://llvm.googlesource.com/llvm-project/libc` |
+| `dart-sdk/third_party/libc` | `https://llvm.googlesource.com/llvm-project/libc` |
-| `dart-sdk-new/third_party/libcxx` | `https://llvm.googlesource.com/llvm-project/libcxx` |
+| `dart-sdk/third_party/libcxx` | `https://llvm.googlesource.com/llvm-project/libcxx` |
-| `dart-sdk-new/third_party/libcxxabi` | `https://llvm.googlesource.com/llvm-project/libcxxabi` |
+| `dart-sdk/third_party/libcxxabi` | `https://llvm.googlesource.com/llvm-project/libcxxabi` |
-| `dart-sdk-new/third_party/markupsafe` | `https://chromium.googlesource.com/chromium/src/third_party/markupsafe.git` |
+| `dart-sdk/third_party/markupsafe` | `https://chromium.googlesource.com/chromium/src/third_party/markupsafe.git` |
-| `dart-sdk-new/third_party/mini_chromium/mini_chromium` | `https://chromium.googlesource.com/chromium/mini_chromium` |
+| `dart-sdk/third_party/mini_chromium/mini_chromium` | `https://chromium.googlesource.com/chromium/mini_chromium` |
-| `dart-sdk-new/third_party/perfetto/src` | `https://chromium.googlesource.com/external/github.com/google/perfetto` |
+| `dart-sdk/third_party/perfetto/src` | `https://chromium.googlesource.com/external/github.com/google/perfetto` |
-| `dart-sdk-new/third_party/pkg/core` | `https://dart.googlesource.com/core.git` |
+| `dart-sdk/third_party/pkg/core` | `https://dart.googlesource.com/core.git` |
-| `dart-sdk-new/third_party/pkg/dart_style` | `https://dart.googlesource.com/dart_style.git` |
+| `dart-sdk/third_party/pkg/dart_style` | `https://dart.googlesource.com/dart_style.git` |
-| `dart-sdk-new/third_party/pkg/dartdoc` | `https://dart.googlesource.com/dartdoc.git` |
+| `dart-sdk/third_party/pkg/dartdoc` | `https://dart.googlesource.com/dartdoc.git` |
-| `dart-sdk-new/third_party/pkg/ecosystem` | `https://dart.googlesource.com/ecosystem.git` |
+| `dart-sdk/third_party/pkg/ecosystem` | `https://dart.googlesource.com/ecosystem.git` |
-| `dart-sdk-new/third_party/pkg/http` | `https://dart.googlesource.com/http.git` |
+| `dart-sdk/third_party/pkg/http` | `https://dart.googlesource.com/http.git` |
-| `dart-sdk-new/third_party/pkg/i18n` | `https://dart.googlesource.com/i18n.git` |
+| `dart-sdk/third_party/pkg/i18n` | `https://dart.googlesource.com/i18n.git` |
-| `dart-sdk-new/third_party/pkg/leak_tracker` | `https://dart.googlesource.com/leak_tracker.git` |
+| `dart-sdk/third_party/pkg/leak_tracker` | `https://dart.googlesource.com/leak_tracker.git` |
-| `dart-sdk-new/third_party/pkg/native` | `https://dart.googlesource.com/native.git` |
+| `dart-sdk/third_party/pkg/native` | `https://dart.googlesource.com/native.git` |
-| `dart-sdk-new/third_party/pkg/protobuf` | `https://dart.googlesource.com/protobuf.git` |
+| `dart-sdk/third_party/pkg/protobuf` | `https://dart.googlesource.com/protobuf.git` |
-| `dart-sdk-new/third_party/pkg/pub` | `https://dart.googlesource.com/pub.git` |
+| `dart-sdk/third_party/pkg/pub` | `https://dart.googlesource.com/pub.git` |
-| `dart-sdk-new/third_party/pkg/shelf` | `https://dart.googlesource.com/shelf.git` |
+| `dart-sdk/third_party/pkg/shelf` | `https://dart.googlesource.com/shelf.git` |
-| `dart-sdk-new/third_party/pkg/sync_http` | `https://dart.googlesource.com/sync_http.git` |
+| `dart-sdk/third_party/pkg/sync_http` | `https://dart.googlesource.com/sync_http.git` |
-| `dart-sdk-new/third_party/pkg/tar` | `https://dart.googlesource.com/external/github.com/simolus3/tar.git` |
+| `dart-sdk/third_party/pkg/tar` | `https://dart.googlesource.com/external/github.com/simolus3/tar.git` |
-| `dart-sdk-new/third_party/pkg/test` | `https://dart.googlesource.com/test.git` |
+| `dart-sdk/third_party/pkg/test` | `https://dart.googlesource.com/test.git` |
-| `dart-sdk-new/third_party/pkg/tools` | `https://dart.googlesource.com/tools.git` |
+| `dart-sdk/third_party/pkg/tools` | `https://dart.googlesource.com/tools.git` |
-| `dart-sdk-new/third_party/pkg/vector_math` | `https://dart.googlesource.com/external/github.com/google/vector_math.dart.git` |
+| `dart-sdk/third_party/pkg/vector_math` | `https://dart.googlesource.com/external/github.com/google/vector_math.dart.git` |
-| `dart-sdk-new/third_party/pkg/web` | `https://dart.googlesource.com/web.git` |
+| `dart-sdk/third_party/pkg/web` | `https://dart.googlesource.com/web.git` |
-| `dart-sdk-new/third_party/pkg/webdev` | `https://dart.googlesource.com/webdev.git` |
+| `dart-sdk/third_party/pkg/webdev` | `https://dart.googlesource.com/webdev.git` |
-| `dart-sdk-new/third_party/pkg/webdriver` | `https://dart.googlesource.com/external/github.com/google/webdriver.dart.git` |
+| `dart-sdk/third_party/pkg/webdriver` | `https://dart.googlesource.com/external/github.com/google/webdriver.dart.git` |
-| `dart-sdk-new/third_party/pkg/webkit_inspection_protocol` | `https://dart.googlesource.com/external/github.com/google/webkit_inspection_protocol.dart.git` |
+| `dart-sdk/third_party/pkg/webkit_inspection_protocol` | `https://dart.googlesource.com/external/github.com/google/webkit_inspection_protocol.dart.git` |
-| `dart-sdk-new/third_party/ply` | `https://chromium.googlesource.com/chromium/src/third_party/ply.git` |
+| `dart-sdk/third_party/ply` | `https://chromium.googlesource.com/chromium/src/third_party/ply.git` |
-| `dart-sdk-new/third_party/WebCore` | `https://dart.googlesource.com/webcore.git` |
+| `dart-sdk/third_party/WebCore` | `https://dart.googlesource.com/webcore.git` |
-| `dart-sdk-new/third_party/zlib` | `https://chromium.googlesource.com/chromium/src/third_party/zlib.git` |
+| `dart-sdk/third_party/zlib` | `https://chromium.googlesource.com/chromium/src/third_party/zlib.git` |

scripts/android_runtime_patch_smoke.sh

@@ -0,0 +1,249 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+APP_DIR="${APP_DIR:-$ROOT/testapps/license_flavor_patch_test}"
+FLUTTER_BIN="${FLUTTER_BIN:-$ROOT/flutter/bin/flutter}"
+ADB_BIN="${ADB_BIN:-adb}"
+PACKAGE="${ANDROID_PACKAGE:-com.example.licenseflavorpatchtest.license_flavor_patch_test}"
+ACTIVITY="${ANDROID_ACTIVITY:-com.example.licenseflavorpatchtest.license_flavor_patch_test.MainActivity}"
+RELEASE_VERSION="${ANDROID_RELEASE_VERSION:-1.0+1}"
+LOCAL_ENGINE_SRC_PATH="${LOCAL_ENGINE_SRC_PATH:-$ROOT/flutter/engine/src}"
+LOCAL_ENGINE="${LOCAL_ENGINE:-android_release_arm64}"
+LOCAL_ENGINE_HOST="${LOCAL_ENGINE_HOST:-host_release_arm64}"
+WORK_DIR="${ANDROID_RUNTIME_SMOKE_WORK_DIR:-$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-android-runtime.XXXXXX")}"
+SEED_REMOTE_DIR="${ANDROID_SEED_REMOTE_DIR:-/data/local/tmp/open-shorebird-android-runtime-seed}"
+TARGET_PLATFORM="${ANDROID_TARGET_PLATFORM:-android-arm64}"
+
+if [[ "${KEEP_ANDROID_RUNTIME_SMOKE_ARTIFACTS:-0}" != "1" ]]; then
+  trap 'rm -rf "$WORK_DIR"' EXIT
+fi
+
+ADB=("$ADB_BIN")
+if [[ -n "${ANDROID_SERIAL:-}" ]]; then
+  ADB+=("-s" "$ANDROID_SERIAL")
+fi
+
+adb_cmd() {
+  "${ADB[@]}" "$@"
+}
+
+adb_shell() {
+  adb_cmd shell "$@"
+}
+
+python_bin() {
+  if command -v python3 >/dev/null 2>&1; then
+    printf '%s\n' python3
+  else
+    printf '%s\n' python
+  fi
+}
+
+require_tool() {
+  local tool="$1"
+  if ! command -v "$tool" >/dev/null 2>&1; then
+    echo "$tool is required" >&2
+    exit 127
+  fi
+}
+
+build_apk() {
+  local license="$1"
+  local output="$2"
+  if [[ "${SKIP_ANDROID_BUILDS:-0}" == "1" ]]; then
+    local env_name
+    case "$license" in
+      free) env_name=ANDROID_FREE_APK ;;
+      pro) env_name=ANDROID_PRO_APK ;;
+      *)
+        echo "Unsupported license variant: $license" >&2
+        exit 64
+        ;;
+    esac
+    local existing="${!env_name:-}"
+    if [[ -z "$existing" || ! -f "$existing" ]]; then
+      echo "SKIP_ANDROID_BUILDS=1 requires $env_name to point at an APK" >&2
+      exit 66
+    fi
+    cp "$existing" "$output"
+    return
+  fi
+
+  (
+    cd "$APP_DIR"
+    "$FLUTTER_BIN" build apk --release \
+      --target-platform "$TARGET_PLATFORM" \
+      --local-engine-src-path="$LOCAL_ENGINE_SRC_PATH" \
+      --local-engine="$LOCAL_ENGINE" \
+      --local-engine-host="$LOCAL_ENGINE_HOST" \
+      --dart-define="LICENSE_TYPE=$license"
+  )
+  cp "$APP_DIR/build/app/outputs/flutter-apk/app-release.apk" "$output"
+}
+
+extract_libapp() {
+  local apk="$1"
+  local output="$2"
+  local py
+  py="$(python_bin)"
+  "$py" - "$apk" "$output" <<'PY'
+import pathlib
+import sys
+import zipfile
+
+apk_path = pathlib.Path(sys.argv[1])
+output_path = pathlib.Path(sys.argv[2])
+with zipfile.ZipFile(apk_path) as archive:
+    candidates = [
+        name for name in archive.namelist()
+        if name.endswith("/libapp.so") and "arm64-v8a/" in name
+    ]
+    if not candidates:
+        raise SystemExit(f"missing arm64 libapp.so in {apk_path}")
+    output_path.write_bytes(archive.read(candidates[0]))
+PY
+}
+
+wait_for_text() {
+  local expected="$1"
+  local dump="$WORK_DIR/window.xml"
+  for _ in $(seq 1 "${ANDROID_UI_WAIT_ATTEMPTS:-80}"); do
+    adb_shell uiautomator dump /sdcard/open_shorebird_window.xml >/dev/null 2>&1 || true
+    adb_cmd exec-out cat /sdcard/open_shorebird_window.xml >"$dump" 2>/dev/null || true
+    if grep -q "$expected" "$dump"; then
+      return 0
+    fi
+    sleep 0.25
+  done
+  echo "Timed out waiting for Android UI text: $expected" >&2
+  echo "Last uiautomator dump:" >&2
+  sed -n '1,120p' "$dump" >&2 || true
+  return 70
+}
+
+start_app() {
+  adb_shell am force-stop "$PACKAGE" >/dev/null 2>&1 || true
+  adb_shell am start -W -n "$PACKAGE/$ACTIVITY" >/dev/null
+}
+
+can_seed_with_run_as() {
+  adb_shell run-as "$PACKAGE" sh -c 'test -d files' >/dev/null 2>&1
+}
+
+can_seed_with_root() {
+  if adb_shell sh -c 'test "$(id -u)" = "0"' >/dev/null 2>&1; then
+    return 0
+  fi
+  adb_cmd root >/dev/null 2>&1 || true
+  adb_cmd wait-for-device >/dev/null 2>&1 || true
+  adb_shell sh -c 'test "$(id -u)" = "0"' >/dev/null 2>&1
+}
+
+seed_with_run_as() {
+  adb_shell run-as "$PACKAGE" sh -c \
+    "mkdir -p files && rm -rf files/shorebird_updater && cp -R '$SEED_REMOTE_DIR/shorebird_updater' files/"
+}
+
+seed_with_root() {
+  local target="/data/data/$PACKAGE/files"
+  local owner
+  owner="$(adb_shell sh -c "stat -c '%u:%g' '$target'" | tr -d '\r')"
+  adb_shell sh -c \
+    "rm -rf '$target/shorebird_updater' && cp -R '$SEED_REMOTE_DIR/shorebird_updater' '$target/' && chown -R '$owner' '$target/shorebird_updater'"
+}
+
+prepare_seed() {
+  local libapp="$1"
+  local seed_root="$WORK_DIR/seed/shorebird_updater"
+  local size
+  size="$(wc -c <"$libapp" | tr -d ' ')"
+  rm -rf "$WORK_DIR/seed"
+  mkdir -p "$seed_root/patches/1"
+  cp "$libapp" "$seed_root/patches/1/dlc.vmcode"
+  cat >"$seed_root/state.json" <<EOF
+{
+  "client_id": "android-runtime-smoke",
+  "release_version": "$RELEASE_VERSION",
+  "queued_events": []
+}
+EOF
+  cat >"$seed_root/pointers.json" <<'EOF'
+{
+  "next_boot_patch": 1,
+  "last_booted_patch": null,
+  "currently_booting_patch": null,
+  "boot_started_at": null
+}
+EOF
+  cat >"$seed_root/patches/1/state.json" <<EOF
+{
+  "kind": "Installed",
+  "signature": null,
+  "size": $size
+}
+EOF
+  adb_shell rm -rf "$SEED_REMOTE_DIR" >/dev/null 2>&1 || true
+  adb_shell mkdir -p "$SEED_REMOTE_DIR" >/dev/null
+  adb_cmd push "$seed_root" "$SEED_REMOTE_DIR/" >/dev/null
+  echo "seeded_patch_size=$size"
+}
+
+require_tool "$ADB_BIN"
+require_tool "$FLUTTER_BIN"
+require_tool java
+
+adb_cmd start-server >/dev/null
+device_count="$(adb_cmd devices | awk 'NR > 1 && $2 == "device" { count++ } END { print count + 0 }')"
+if [[ "$device_count" -lt 1 ]]; then
+  echo "No Android device or emulator is connected." >&2
+  echo "Start an emulator/device, then rerun this script. Use ANDROID_SERIAL to pick a device." >&2
+  exit 69
+fi
+if [[ "$device_count" -gt 1 && -z "${ANDROID_SERIAL:-}" ]]; then
+  echo "Multiple Android devices are connected; set ANDROID_SERIAL." >&2
+  adb_cmd devices -l >&2
+  exit 64
+fi
+
+free_apk="$WORK_DIR/free.apk"
+pro_apk="$WORK_DIR/pro.apk"
+pro_libapp="$WORK_DIR/pro-libapp.so"
+
+build_apk free "$free_apk"
+build_apk pro "$pro_apk"
+extract_libapp "$pro_apk" "$pro_libapp"
+
+adb_cmd uninstall "$PACKAGE" >/dev/null 2>&1 || true
+adb_cmd install -r "$free_apk" >/dev/null
+
+start_app
+wait_for_text 'license:free'
+wait_for_text 'pro-feature:off'
+echo "android_base_status=license:free/pro-feature:off"
+
+prepare_seed "$pro_libapp"
+if can_seed_with_run_as; then
+  seed_with_run_as
+  echo "android_seed_mode=run-as"
+elif can_seed_with_root; then
+  seed_with_root
+  echo "android_seed_mode=root"
+else
+  cat >&2 <<EOF
+Unable to seed the Android app-private updater directory.
+
+Use a debuggable build/device where 'adb shell run-as $PACKAGE' works, or use
+a rooted emulator/device where 'adb root' works. The smoke seed target is:
+  /data/data/$PACKAGE/files/shorebird_updater
+EOF
+  exit 77
+fi
+
+start_app
+wait_for_text 'license:pro'
+wait_for_text 'pro-feature:enabled'
+echo "android_patch_status=license:pro/pro-feature:enabled"
+
+adb_shell am force-stop "$PACKAGE" >/dev/null 2>&1 || true
+echo "android_runtime_patch_smoke=passed"

scripts/assemble_artifact_mirror.sh

@@ -0,0 +1,124 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+usage() {
+  cat >&2 <<'EOF'
+usage: assemble_artifact_mirror.sh <downloaded-workflow-artifacts-dir> <output-mirror-root>
+
+Copies every publish-ready shorebird/ mirror subtree from downloaded GitHub
+Actions artifacts into <output-mirror-root>. Engine archives are extracted and
+scanned for nested mirror/shorebird trees. Existing files may be reused only
+when their bytes match.
+EOF
+}
+
+if [[ "$#" -ne 2 ]]; then
+  usage
+  exit 64
+fi
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+INPUT_DIR="$1"
+OUTPUT_DIR="$2"
+
+if [[ ! -d "$INPUT_DIR" ]]; then
+  echo "input artifact directory does not exist: $INPUT_DIR" >&2
+  exit 66
+fi
+
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-mirror.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+mkdir -p "$OUTPUT_DIR"
+
+FOUND_TREES=0
+
+copy_tree_to_shorebird_prefix() {
+  local tree="$1"
+  local prefix="$2"
+  local source_file rel_file target_file
+
+  FOUND_TREES=$((FOUND_TREES + 1))
+  while IFS= read -r -d '' source_file; do
+    rel_file="${source_file#"$tree"/}"
+    target_file="$OUTPUT_DIR/shorebird/$prefix$rel_file"
+    mkdir -p "$(dirname "$target_file")"
+    if [[ -e "$target_file" ]]; then
+      if ! cmp -s "$source_file" "$target_file"; then
+        echo "conflicting mirror file: shorebird/$prefix$rel_file" >&2
+        echo "  existing: $target_file" >&2
+        echo "  incoming: $source_file" >&2
+        exit 70
+      fi
+      continue
+    fi
+    cp -p "$source_file" "$target_file"
+  done < <(find "$tree" -type f -print0)
+}
+
+copy_shorebird_tree() {
+  copy_tree_to_shorebird_prefix "$1" ""
+}
+
+scan_for_shorebird_trees() {
+  local search_root="$1"
+  local tree
+
+  while IFS= read -r -d '' tree; do
+    copy_shorebird_tree "$tree"
+  done < <(find "$search_root" -type d -name shorebird -print0)
+}
+
+scan_for_downloaded_metadata_trees() {
+  local search_root="$1"
+  local manifest_path metadata_dir engine_revision
+
+  # actions/upload-artifact strips the non-wildcard prefix from
+  # artifacts/mirror/shorebird/**/artifacts_manifest.yaml, so the downloaded
+  # mirror-metadata artifact is shaped as <engine>/artifacts_manifest.yaml.
+  while IFS= read -r -d '' manifest_path; do
+    if [[ "$manifest_path" == */shorebird/* ]]; then
+      continue
+    fi
+
+    metadata_dir="$(dirname "$manifest_path")"
+    engine_revision="$(basename "$metadata_dir")"
+    copy_tree_to_shorebird_prefix "$metadata_dir" "$engine_revision/"
+  done < <(find "$search_root" -type f -name artifacts_manifest.yaml -print0)
+}
+
+scan_for_shorebird_trees "$INPUT_DIR"
+scan_for_downloaded_metadata_trees "$INPUT_DIR"
+
+archive_index=0
+while IFS= read -r -d '' archive_path; do
+  archive_index=$((archive_index + 1))
+  extract_dir="$TMP_DIR/archive-$archive_index"
+  mkdir -p "$extract_dir"
+  "$PYTHON_BIN" "$ROOT/scripts/safe_extract_tar.py" "$archive_path" "$extract_dir"
+  scan_for_shorebird_trees "$extract_dir"
+done < <(find "$INPUT_DIR" -type f \( -name '*.tar.gz' -o -name '*.tgz' \) -print0)
+
+if [[ "$FOUND_TREES" -eq 0 ]]; then
+  echo "no shorebird/ mirror subtrees found under $INPUT_DIR" >&2
+  exit 65
+fi
+
+while IFS= read -r -d '' mirror_file; do
+  if [[ "$mirror_file" == *.sha256 ]]; then
+    continue
+  fi
+  sidecar="$mirror_file.sha256"
+  if [[ ! -f "$sidecar" ]]; then
+    "$ROOT/scripts/write_sha256.sh" "$mirror_file" "$sidecar"
+  fi
+done < <(find "$OUTPUT_DIR/shorebird" -type f -print0)
+
+"$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" "$OUTPUT_DIR"
+
+echo "assembled artifact mirror at $OUTPUT_DIR"

scripts/check_ci_capacity.sh

@@ -0,0 +1,55 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+MIN_FREE_DISK_GB="${CI_MIN_FREE_DISK_GB:-0}"
+CHECK_PATH="${CI_CAPACITY_PATH:-$PWD}"
+AVAILABLE_DISK_KB_OVERRIDE="${CI_AVAILABLE_DISK_KB_OVERRIDE:-}"
+
+fail() {
+  echo "error: $*" >&2
+  exit 70
+}
+
+case "$MIN_FREE_DISK_GB" in
+  ''|*[!0-9]*)
+    fail "CI_MIN_FREE_DISK_GB must be a non-negative integer, got '$MIN_FREE_DISK_GB'"
+    ;;
+esac
+
+if [[ "$MIN_FREE_DISK_GB" == "0" ]]; then
+  echo "CI capacity check skipped because CI_MIN_FREE_DISK_GB=0"
+  exit 0
+fi
+
+if [[ ! -e "$CHECK_PATH" ]]; then
+  fail "capacity check path does not exist: $CHECK_PATH"
+fi
+
+available_disk_kb() {
+  if [[ -n "$AVAILABLE_DISK_KB_OVERRIDE" ]]; then
+    case "$AVAILABLE_DISK_KB_OVERRIDE" in
+      *[!0-9]*)
+        fail "CI_AVAILABLE_DISK_KB_OVERRIDE must be an integer, got '$AVAILABLE_DISK_KB_OVERRIDE'"
+        ;;
+    esac
+    printf '%s\n' "$AVAILABLE_DISK_KB_OVERRIDE"
+    return
+  fi
+  df -Pk "$CHECK_PATH" | awk 'NR == 2 { print $4 }'
+}
+
+available_kb="$(available_disk_kb)"
+case "$available_kb" in
+  ''|*[!0-9]*)
+    fail "could not determine available disk space for $CHECK_PATH"
+    ;;
+esac
+
+required_kb=$((MIN_FREE_DISK_GB * 1024 * 1024))
+available_gb=$((available_kb / 1024 / 1024))
+
+echo "CI capacity: ${available_gb} GiB free at $CHECK_PATH; required: ${MIN_FREE_DISK_GB} GiB"
+
+if (( available_kb < required_kb )); then
+  fail "runner has insufficient free disk for the heavy SDK/engine build. Use a larger or self-hosted runner label, or free disk before this step."
+fi

scripts/free_ci_disk_linux.sh

@@ -0,0 +1,48 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ "${GITHUB_ACTIONS:-}" != "true" ]]; then
+  echo "Refusing to free disk outside GitHub Actions." >&2
+  exit 64
+fi
+
+if [[ "$(uname -s)" != "Linux" ]]; then
+  echo "Skipping Linux disk cleanup on $(uname -s)."
+  exit 0
+fi
+
+if [[ "${CI_FREE_DISK_SPACE:-1}" == "0" ]]; then
+  echo "Skipping disk cleanup because CI_FREE_DISK_SPACE=0."
+  df -h
+  exit 0
+fi
+
+if [[ "${RUNNER_ENVIRONMENT:-github-hosted}" != "github-hosted" &&
+      "${CI_FREE_DISK_SPACE_FORCE:-0}" != "1" ]]; then
+  echo "Skipping disk cleanup on ${RUNNER_ENVIRONMENT} runner."
+  echo "Set CI_FREE_DISK_SPACE_FORCE=1 to opt in on non-hosted runners."
+  df -h
+  exit 0
+fi
+
+echo "Disk before cleanup:"
+df -h
+
+# GitHub-hosted Ubuntu images include large toolchains that are unrelated to
+# Dart SDK, Flutter engine, and updater builds. Remove only well-known cache
+# directories on ephemeral GitHub Actions runners.
+for path in \
+  /opt/ghc \
+  /opt/hostedtoolcache/CodeQL \
+  /usr/local/.ghcup \
+  /usr/local/lib/android/sdk \
+  /usr/local/share/boost \
+  /usr/share/dotnet; do
+  if [[ -e "$path" ]]; then
+    echo "Removing $path"
+    sudo rm -rf "$path"
+  fi
+done
+
+echo "Disk after cleanup:"
+df -h

scripts/linux_runtime_patch_smoke.sh

@@ -0,0 +1,238 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+SOURCE_APP_DIR="${SOURCE_APP_DIR:-$ROOT/testapps/license_flavor_patch_test}"
+FLUTTER_BIN="${FLUTTER_BIN:-$ROOT/flutter/bin/flutter}"
+APP_ID="${SHOREBIRD_APP_ID:-license-flavor-patch-test}"
+LOCAL_ENGINE_SRC_PATH="${LOCAL_ENGINE_SRC_PATH:-$ROOT/flutter/engine/src}"
+DEFAULT_LOCAL_ENGINE="linux_release_x64"
+if [[ ! -d "$LOCAL_ENGINE_SRC_PATH/out/$DEFAULT_LOCAL_ENGINE" &&
+      -d "$LOCAL_ENGINE_SRC_PATH/out/host_release" ]]; then
+  DEFAULT_LOCAL_ENGINE="host_release"
+fi
+LOCAL_ENGINE="${LOCAL_ENGINE:-$DEFAULT_LOCAL_ENGINE}"
+LOCAL_ENGINE_HOST="${LOCAL_ENGINE_HOST:-$LOCAL_ENGINE}"
+WORK_DIR="${LINUX_RUNTIME_SMOKE_WORK_DIR:-$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-linux-runtime.XXXXXX")}"
+APP_COPY="$WORK_DIR/app"
+HOME_DIR="$WORK_DIR/home"
+
+if [[ "${KEEP_LINUX_RUNTIME_SMOKE_ARTIFACTS:-0}" != "1" ]]; then
+  trap 'rm -rf "$WORK_DIR"' EXIT
+fi
+
+require_tool() {
+  local tool="$1"
+  if ! command -v "$tool" >/dev/null 2>&1; then
+    echo "$tool is required" >&2
+    exit 127
+  fi
+}
+
+python_bin() {
+  if command -v python3 >/dev/null 2>&1; then
+    printf '%s\n' python3
+  else
+    printf '%s\n' python
+  fi
+}
+
+copy_app_fixture() {
+  mkdir -p "$APP_COPY"
+  (
+    cd "$SOURCE_APP_DIR"
+    tar \
+      --exclude='./build' \
+      --exclude='./.dart_tool' \
+      --exclude='./android/.gradle' \
+      --exclude='./ios/Pods' \
+      --exclude='./macos/Flutter/ephemeral' \
+      -cf - .
+  ) | tar -C "$APP_COPY" -xf -
+}
+
+ensure_linux_platform() {
+  if [[ -d "$APP_COPY/linux" ]]; then
+    return
+  fi
+  (
+    cd "$APP_COPY"
+    "$FLUTTER_BIN" create --platforms=linux --project-name=license_flavor_patch_test .
+  )
+}
+
+build_linux_bundle() {
+  local license="$1"
+  local output="$2"
+  (
+    cd "$APP_COPY"
+    "$FLUTTER_BIN" build linux --release \
+      --local-engine-src-path="$LOCAL_ENGINE_SRC_PATH" \
+      --local-engine="$LOCAL_ENGINE" \
+      --local-engine-host="$LOCAL_ENGINE_HOST" \
+      --dart-define="LICENSE_TYPE=$license"
+  )
+  local bundle
+  bundle="$(find "$APP_COPY/build/linux" -path '*/release/bundle' -type d -print -quit)"
+  if [[ -z "$bundle" || ! -x "$bundle/license_flavor_patch_test" ]]; then
+    echo "Failed to find Linux release bundle under $APP_COPY/build/linux" >&2
+    exit 66
+  fi
+  rm -rf "$output"
+  cp -a "$bundle" "$output"
+}
+
+release_version_for_bundle() {
+  local bundle="$1"
+  local version_json="$bundle/data/flutter_assets/version.json"
+  local py
+  py="$(python_bin)"
+  "$py" - "$version_json" <<'PY'
+import json
+import pathlib
+import sys
+
+version = json.loads(pathlib.Path(sys.argv[1]).read_text())
+build_name = str(version.get("version", ""))
+build_number = str(version.get("build_number", ""))
+if build_number:
+    print(f"{build_name}+{build_number}")
+else:
+    print(build_name)
+PY
+}
+
+run_saved_app() {
+  local label="$1"
+  local bundle="$2"
+  local stdout="$WORK_DIR/$label.stdout"
+  local stderr="$WORK_DIR/$label.stderr"
+  local tmp_status="$WORK_DIR/tmp/license_flavor_patch_status.txt"
+  local home_status="$HOME_DIR/Library/Application Support/license_flavor_patch_status.txt"
+
+  rm -f "$tmp_status" "$home_status"
+  mkdir -p "$WORK_DIR/tmp" "$HOME_DIR"
+
+  local -a app_command=(env HOME="$HOME_DIR" TMPDIR="$WORK_DIR/tmp" "$bundle/license_flavor_patch_test")
+  if [[ "${LINUX_RUNTIME_SMOKE_XVFB:-auto}" != "0" && -z "${DISPLAY:-}" && "$(command -v xvfb-run || true)" != "" ]]; then
+    app_command=(xvfb-run -a "${app_command[@]}")
+  fi
+
+  "${app_command[@]}" >"$stdout" 2>"$stderr" &
+  local pid=$!
+  for _ in $(seq 1 "${LINUX_RUNTIME_WAIT_ATTEMPTS:-120}"); do
+    if [[ -f "$tmp_status" || -f "$home_status" ]]; then
+      break
+    fi
+    if ! kill -0 "$pid" 2>/dev/null; then
+      break
+    fi
+    sleep 0.25
+  done
+  if kill -0 "$pid" 2>/dev/null; then
+    kill "$pid" 2>/dev/null || true
+    wait "$pid" 2>/dev/null || true
+  else
+    wait "$pid" 2>/dev/null || true
+  fi
+
+  echo "${label}_stdout=$stdout"
+  echo "${label}_stderr=$stderr"
+  if [[ -f "$tmp_status" ]]; then
+    echo "${label}_status_file=$tmp_status"
+    cat "$tmp_status"
+  elif [[ -f "$home_status" ]]; then
+    echo "${label}_status_file=$home_status"
+    cat "$home_status"
+  else
+    echo "${label}_status_file_missing" >&2
+    echo "--- $label stderr ---" >&2
+    sed -n '1,180p' "$stderr" >&2 || true
+    return 70
+  fi
+}
+
+read_launch_status() {
+  local tmp_status="$WORK_DIR/tmp/license_flavor_patch_status.txt"
+  local home_status="$HOME_DIR/Library/Application Support/license_flavor_patch_status.txt"
+  if [[ -f "$tmp_status" ]]; then
+    cat "$tmp_status"
+  elif [[ -f "$home_status" ]]; then
+    cat "$home_status"
+  fi
+}
+
+require_status() {
+  local label="$1"
+  local expected_license="$2"
+  local expected_feature="$3"
+  local status
+  status="$(read_launch_status)"
+  if ! grep -q "license:$expected_license" <<<"$status" ||
+     ! grep -q "pro-feature:$expected_feature" <<<"$status"; then
+    echo "$label Linux app did not report expected status." >&2
+    echo "Expected: license:$expected_license / pro-feature:$expected_feature" >&2
+    echo "Actual:" >&2
+    printf '%s\n' "$status" >&2
+    exit 70
+  fi
+}
+
+seed_patch() {
+  local pro_bundle="$1"
+  local release_version="$2"
+  local patch_file="$pro_bundle/lib/libapp.so"
+  local state_root="$HOME_DIR/.shorebird_cache/shorebird_updater/$APP_ID"
+  local size
+  size="$(wc -c <"$patch_file" | tr -d ' ')"
+
+  rm -rf "$state_root"
+  mkdir -p "$state_root/patches/1"
+  cp "$patch_file" "$state_root/patches/1/dlc.vmcode"
+  cat >"$state_root/state.json" <<EOF
+{
+  "client_id": "linux-runtime-smoke",
+  "release_version": "$release_version",
+  "queued_events": []
+}
+EOF
+  cat >"$state_root/pointers.json" <<'EOF'
+{
+  "next_boot_patch": 1,
+  "last_booted_patch": null,
+  "currently_booting_patch": null,
+  "boot_started_at": null
+}
+EOF
+  cat >"$state_root/patches/1/state.json" <<EOF
+{
+  "kind": "Installed",
+  "signature": null,
+  "size": $size
+}
+EOF
+  echo "linux_seeded_patch=$state_root/patches/1/dlc.vmcode"
+  echo "linux_seeded_patch_size=$size"
+}
+
+require_tool "$FLUTTER_BIN"
+require_tool tar
+
+copy_app_fixture
+ensure_linux_platform
+
+free_bundle="$WORK_DIR/free-bundle"
+pro_bundle="$WORK_DIR/pro-bundle"
+
+build_linux_bundle free "$free_bundle"
+build_linux_bundle pro "$pro_bundle"
+
+release_version="$(release_version_for_bundle "$free_bundle")"
+
+run_saved_app base "$free_bundle"
+require_status base free off
+seed_patch "$pro_bundle" "$release_version"
+run_saved_app patch "$free_bundle"
+require_status patch pro enabled
+
+echo "linux_runtime_patch_smoke=passed"

scripts/platform_test_common.sh

@@ -6,6 +6,7 @@ ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 DART_BIN="${DART_BIN:-dart}"
 FLUTTER_BIN="${FLUTTER_BIN:-flutter}"
 GO_BIN="${GO_BIN:-go}"
+CARGO_BIN="${CARGO_BIN:-cargo}"
 
 run() {
   echo
@@ -23,6 +24,7 @@ require_command() {
 require_command git
 require_command "$DART_BIN"
 require_command "$GO_BIN"
+require_command "$CARGO_BIN"
 
 if [[ "$PLATFORM" == "macos" ]]; then
   if command -v xcodebuild >/dev/null 2>&1; then
@@ -37,9 +39,13 @@ run "$ROOT/scripts/write_gclient.sh" "$PLATFORM"
 run "$ROOT/scripts/sync_open_sources.sh"
 
 export PATH="$ROOT/depot_tools:$PATH"
+export DEPOT_TOOLS_UPDATE="${DEPOT_TOOLS_UPDATE:-0}"
 if [[ "${SKIP_GCLIENT_SYNC:-0}" != "1" ]]; then
   require_command gclient
   run gclient sync --no-history
+  if [[ "${INCLUDE_ENGINE_DEPS:-0}" == "1" && -f "$ROOT/flutter/.gclient" ]]; then
+    run bash -lc "cd '$ROOT/flutter' && gclient sync --no-history"
+  fi
 else
   echo
   echo "==> skipping gclient sync because SKIP_GCLIENT_SYNC=1"
@@ -51,16 +57,20 @@ if [[ "${SKIP_TESTS:-0}" == "1" ]]; then
   exit 0
 fi
 
-run bash -lc "cd '$ROOT/shorebird/packages/shorebird_cli' && '$DART_BIN' pub get && '$DART_BIN' test test/src/user_config_test.dart test/src/shorebird_env_test.dart test/src/shorebird_cli_command_runner_test.dart test/src/commands/init_command_test.dart"
+run bash -lc "cd '$ROOT/shorebird' && '$DART_BIN' pub get"
+run bash -lc "cd '$ROOT/shorebird/packages/shorebird_cli' && '$DART_BIN' pub get && '$DART_BIN' test test/src/user_config_test.dart test/src/shorebird_env_test.dart test/src/shorebird_cli_command_runner_test.dart test/src/commands/doctor_command_test.dart test/src/commands/init_command_test.dart test/src/cache_test.dart test/src/shorebird_process_test.dart test/src/network_checker_test.dart test/src/shorebird_web_console_test.dart test/src/auth/auth_test.dart test/src/commands/login_command_test.dart test/src/commands/login_ci_command_test.dart test/src/commands/release/aar_releaser_test.dart test/src/shorebird_validator_test.dart test/src/shorebird_flutter_test.dart test/src/shorebird_artifacts_test.dart test/src/artifact_builder/artifact_builder_test.dart test/src/config/shorebird_yaml_test.dart test/src/commands/patch/ios_patcher_test.dart"
+run bash -lc "cd '$ROOT/shorebird' && '$DART_BIN' test packages/shorebird_code_push_client/test/src/code_push_client_test.dart"
+run bash -lc "cd '$ROOT/shorebird' && '$DART_BIN' test packages/artifact_proxy/test/artifact_proxy_test.dart packages/artifact_proxy/test/server_bin_test.dart packages/artifact_proxy/test/src/artifact_manifest_client_test.dart"
 run bash -lc "cd '$ROOT/shorebird/packages/open_aot_patch_tools' && '$DART_BIN' pub get && '$DART_BIN' test"
+run "$CARGO_BIN" test --manifest-path "$ROOT/updater/library/Cargo.toml"
 run bash -lc "cd '$ROOT/shorebird-server' && '$GO_BIN' test ./..."
 
 AOT_PATCH_BUILD_DIR="${AOT_PATCH_BUILD_DIR:-}"
 if [[ -z "$AOT_PATCH_BUILD_DIR" ]]; then
   for candidate in \
-    "$ROOT/dart-sdk-new/xcodebuild/ReleaseARM64" \
+    "$ROOT/dart-sdk/xcodebuild/ReleaseARM64" \
-    "$ROOT/dart-sdk-new/out/ReleaseARM64AotPatch" \
+    "$ROOT/dart-sdk/out/ReleaseARM64AotPatch" \
-    "$ROOT/dart-sdk-new/out/ReleaseX64AotPatch"; do
+    "$ROOT/dart-sdk/out/ReleaseX64AotPatch"; do
     if [[ -f "$candidate/args.gn" ]]; then
       AOT_PATCH_BUILD_DIR="$candidate"
       break

scripts/safe_extract_tar.py

@@ -0,0 +1,117 @@
+#!/usr/bin/env python3
+from __future__ import annotations
+
+import argparse
+from pathlib import Path, PurePosixPath
+import shutil
+import sys
+import tarfile
+
+
+def fail(message: str) -> None:
+    print(f"error: {message}", file=sys.stderr)
+    raise SystemExit(70)
+
+
+def safe_member_name(member: tarfile.TarInfo) -> str | None:
+    name = member.name
+    if member.isdir():
+        name = name.rstrip("/")
+    if not name or name == ".":
+        return None
+    if "\\" in name or "\x00" in name:
+        return None
+    if any(ord(character) < 32 for character in name):
+        return None
+
+    candidate = PurePosixPath(name)
+    if candidate.is_absolute():
+        return None
+    if any(part in ("", ".", "..") for part in candidate.parts):
+        return None
+    if candidate.parts and ":" in candidate.parts[0]:
+        return None
+    return candidate.as_posix()
+
+
+def validate_members(archive_path: Path, members: list[tarfile.TarInfo]) -> None:
+    member_types: dict[str, str] = {}
+    for member in members:
+        safe_name = safe_member_name(member)
+        if safe_name is None:
+            fail(f"{archive_path}: unsafe archive member path {member.name!r}")
+        if not (member.isdir() or member.isfile()):
+            fail(f"{archive_path}: unsupported archive member type {member.name!r}")
+
+        member_type = "dir" if member.isdir() else "file"
+        previous_type = member_types.get(safe_name)
+        if previous_type is None:
+            member_types[safe_name] = member_type
+            continue
+        if previous_type != "dir" or member_type != "dir":
+            fail(f"{archive_path}: duplicate archive member path {member.name!r}")
+
+
+def ensure_within_root(archive_path: Path, extract_root: Path, target: Path, name: str) -> None:
+    try:
+        target.relative_to(extract_root)
+    except ValueError:
+        fail(f"{archive_path}: archive member escapes extraction root {name!r}")
+
+
+def extract_safe_tar_archive(archive_path: Path, extract_dir: Path) -> None:
+    extract_root = extract_dir.resolve()
+    extracted_files: set[Path] = set()
+
+    try:
+        with tarfile.open(archive_path, "r:*") as archive:
+            members = archive.getmembers()
+            validate_members(archive_path, members)
+
+            for member in members:
+                safe_name = safe_member_name(member)
+                assert safe_name is not None
+                target = (extract_root / safe_name).resolve()
+                ensure_within_root(archive_path, extract_root, target, member.name)
+
+                if member.isdir():
+                    if target in extracted_files:
+                        fail(f"{archive_path}: directory collides with file {member.name!r}")
+                    target.mkdir(parents=True, exist_ok=True)
+                    continue
+
+                for parent in target.parents:
+                    if parent == extract_root:
+                        break
+                    if parent in extracted_files:
+                        fail(f"{archive_path}: file parent collides with file {member.name!r}")
+
+                if target.exists() and not target.is_file():
+                    fail(f"{archive_path}: file collides with directory {member.name!r}")
+                target.parent.mkdir(parents=True, exist_ok=True)
+                source = archive.extractfile(member)
+                if source is None:
+                    fail(f"{archive_path}: unable to read archive member {member.name!r}")
+                with source, target.open("wb") as output:
+                    shutil.copyfileobj(source, output)
+                target.chmod(member.mode & 0o777)
+                extracted_files.add(target)
+    except tarfile.TarError as error:
+        fail(f"{archive_path}: invalid tar archive: {error}")
+
+
+def main() -> int:
+    parser = argparse.ArgumentParser(
+        description="Safely extract a tar archive containing only files and directories.",
+    )
+    parser.add_argument("archive", type=Path)
+    parser.add_argument("extract_dir", type=Path)
+    args = parser.parse_args()
+
+    args.extract_dir.mkdir(parents=True, exist_ok=True)
+    extract_safe_tar_archive(args.archive, args.extract_dir)
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

scripts/sync_flutter_prebuilt_dart_sdk.sh

@@ -0,0 +1,67 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+HOST_CONFIG="${1:-linux-x64}"
+DART_SDK_SOURCE="${DART_SDK_SOURCE:-$ROOT/dart-sdk/tools/sdks/dart-sdk}"
+TARGET="$ROOT/flutter/engine/src/flutter/prebuilts/$HOST_CONFIG/dart-sdk"
+
+relative_path() {
+  python3 - "$1" "$2" <<'PY'
+import os
+import sys
+print(os.path.relpath(sys.argv[2], os.path.dirname(sys.argv[1])))
+PY
+}
+
+real_path() {
+  python3 - "$1" <<'PY'
+import os
+import sys
+print(os.path.realpath(sys.argv[1]))
+PY
+}
+
+case "$HOST_CONFIG" in
+  linux-x64|macos-x64|macos-arm64)
+    ;;
+  *)
+    echo "unsupported Flutter prebuilt Dart SDK host config: $HOST_CONFIG" >&2
+    exit 64
+    ;;
+esac
+
+if [[ ! -d "$DART_SDK_SOURCE" ]]; then
+  echo "missing Dart tool SDK source: $DART_SDK_SOURCE" >&2
+  exit 66
+fi
+
+for required in \
+  bin/dart \
+  bin/dartaotruntime \
+  bin/snapshots/dartdevc_aot.dart.snapshot \
+  bin/snapshots/kernel_worker_aot.dart.snapshot
+do
+  if [[ ! -e "$DART_SDK_SOURCE/$required" ]]; then
+    echo "Dart tool SDK is missing $required: $DART_SDK_SOURCE" >&2
+    exit 66
+  fi
+done
+
+mkdir -p "$(dirname "$TARGET")"
+
+if [[ -L "$TARGET" ]]; then
+  source_real="$(real_path "$DART_SDK_SOURCE")"
+  target_real="$(real_path "$TARGET")"
+  if [[ "$source_real" != "$target_real" ]]; then
+    echo "Flutter prebuilt Dart SDK link points at $target_real, expected $source_real" >&2
+    exit 70
+  fi
+elif [[ -e "$TARGET" ]]; then
+  echo "Flutter prebuilt Dart SDK target exists but is not the workspace Dart tool SDK symlink: $TARGET" >&2
+  exit 70
+else
+  ln -s "$(relative_path "$TARGET" "$DART_SDK_SOURCE")" "$TARGET"
+fi
+
+echo "[open-source-sync] Flutter $HOST_CONFIG prebuilt Dart SDK uses $DART_SDK_SOURCE"

scripts/sync_open_sources.sh

@@ -2,16 +2,102 @@
 set -euo pipefail
 
 ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
-DART_SRC="${DART_SRC:-$ROOT/dart-sdk-new}"
+DART_SRC="${DART_SRC:-$ROOT/dart-sdk}"
 DART_TARGET="$ROOT/flutter/engine/src/flutter/third_party/dart"
 UPDATER_SRC="${UPDATER_SRC:-$ROOT/updater}"
-UPDATER_URL="${UPDATER_URL:-https://github.com/shorebirdtech/updater.git}"
+UPDATER_URL="${UPDATER_URL:-}"
 TARGET="$ROOT/flutter/engine/src/flutter/third_party/updater"
 
 is_git_checkout() {
   git -C "$1" rev-parse --git-dir >/dev/null 2>&1
 }
 
+relative_path() {
+  python3 - "$1" "$2" <<'PY'
+import os
+import sys
+print(os.path.relpath(sys.argv[2], os.path.dirname(sys.argv[1])))
+PY
+}
+
+real_path() {
+  python3 - "$1" <<'PY'
+import os
+import sys
+print(os.path.realpath(sys.argv[1]))
+PY
+}
+
+link_checkout() {
+  local target="$1"
+  local source="$2"
+  local label="$3"
+  local rel_target
+  rel_target="$(relative_path "$target" "$source")"
+  ln -s "$rel_target" "$target"
+  echo "[open-source-sync] linked $label checkout into Flutter engine."
+}
+
+is_clean_git_checkout() {
+  [[ -z "$(git -C "$1" status --porcelain)" ]]
+}
+
+reject_forbidden_remotes() {
+  local source="$1"
+  local label="$2"
+  shift 2
+
+  local remotes
+  remotes="$(git -C "$source" remote -v 2>/dev/null || true)"
+  if [[ -z "$remotes" ]]; then
+    return
+  fi
+
+  local forbidden
+  for forbidden in "$@"; do
+    if grep -Fq "$forbidden" <<<"$remotes"; then
+      echo "$label source checkout uses forbidden remote fragment '$forbidden': $source" >&2
+      echo "$remotes" >&2
+      exit 1
+    fi
+  done
+}
+
+ensure_source_link() {
+  local target="$1"
+  local source="$2"
+  local label="$3"
+
+  if [[ ! -d "$source" ]] || ! is_git_checkout "$source"; then
+    echo "$label source checkout is missing: $source" >&2
+    exit 1
+  fi
+
+  if [[ -L "$target" ]]; then
+    local target_real
+    local source_real
+    target_real="$(real_path "$target")"
+    source_real="$(real_path "$source")"
+    if [[ "$target_real" != "$source_real" ]]; then
+      echo "$label target symlink points at $target_real, expected $source_real" >&2
+      exit 1
+    fi
+    echo "[open-source-sync] $label target already links to the workspace checkout."
+  elif is_git_checkout "$target"; then
+    if ! is_clean_git_checkout "$target"; then
+      echo "$label target is a dirty git checkout and cannot be replaced: $target" >&2
+      exit 1
+    fi
+    rm -rf "$target"
+    link_checkout "$target" "$source" "$label"
+  elif [[ -e "$target" ]]; then
+    echo "$label target exists but is not a symlink or git checkout: $target" >&2
+    exit 1
+  else
+    link_checkout "$target" "$source" "$label"
+  fi
+}
+
 echo "[open-source-sync] dart source: $DART_SRC"
 echo "[open-source-sync] dart target: $DART_TARGET"
 echo "[open-source-sync] updater source: $UPDATER_SRC"
@@ -20,60 +106,54 @@ echo "[open-source-sync] target: $TARGET"
 mkdir -p "$(dirname "$DART_TARGET")"
 mkdir -p "$(dirname "$TARGET")"
 
-if [[ -L "$DART_TARGET" ]]; then
+ensure_source_link "$DART_TARGET" "$DART_SRC" "Dart SDK"
-  echo "[open-source-sync] Dart target is already a symlink."
+reject_forbidden_remotes \
-elif is_git_checkout "$DART_TARGET"; then
+  "$DART_SRC" \
-  echo "[open-source-sync] Dart target is already a git checkout."
+  "Dart SDK" \
-elif [[ -e "$DART_TARGET" ]]; then
+  "github.com/dart-lang/sdk" \
-  echo "Dart target exists but is not a symlink or git checkout: $DART_TARGET" >&2
+  "dart.googlesource.com/sdk"
-  exit 1
-elif is_git_checkout "$DART_SRC"; then
-  rel_target="$(python3 - "$DART_TARGET" "$DART_SRC" <<'PY'
-import os
-import sys
-print(os.path.relpath(sys.argv[2], os.path.dirname(sys.argv[1])))
-PY
-)"
-  ln -s "$rel_target" "$DART_TARGET"
-  echo "[open-source-sync] linked Dart SDK checkout into Flutter engine."
-else
-  echo "Dart source checkout is missing: $DART_SRC" >&2
-  exit 1
-fi
 
 if [[ ! -f "$DART_TARGET/runtime/vm/dart_api_impl.h" ]]; then
   echo "Dart checkout is missing runtime/vm/dart_api_impl.h" >&2
   exit 1
 fi
 
-if [[ -L "$TARGET" ]]; then
+if is_git_checkout "$UPDATER_SRC"; then
-  echo "[open-source-sync] updater target is already a symlink."
+  ensure_source_link "$TARGET" "$UPDATER_SRC" "updater submodule"
-  exit 0
+  reject_forbidden_remotes \
-fi
+    "$UPDATER_SRC" \
-
+    "updater submodule" \
-if is_git_checkout "$TARGET"; then
+    "github.com/shorebirdtech/updater" \
-  echo "[open-source-sync] updating existing updater checkout."
+    "github.com/shorebirdtech/shorebird-updater"
-  git -C "$TARGET" fetch --tags origin
+elif [[ -n "$UPDATER_URL" ]]; then
-  git -C "$TARGET" checkout "${UPDATER_REVISION:-main}"
+  if [[ "$UPDATER_URL" == *github.com/shorebirdtech/updater* ||
-  if [[ "${UPDATER_REVISION:-main}" == "main" ]]; then
+        "$UPDATER_URL" == *github.com/shorebirdtech/shorebird-updater* ]]; then
-    git -C "$TARGET" pull --ff-only
+    echo "UPDATER_URL points at a forbidden official Shorebird updater remote: $UPDATER_URL" >&2
+    exit 1
+  fi
+  if [[ -L "$TARGET" ]]; then
+    rm "$TARGET"
+  fi
+  if is_git_checkout "$TARGET"; then
+    echo "[open-source-sync] updating existing updater checkout."
+    git -C "$TARGET" remote set-url origin "$UPDATER_URL"
+    git -C "$TARGET" fetch --tags origin
+    git -C "$TARGET" checkout "${UPDATER_REVISION:-main}"
+    if [[ "${UPDATER_REVISION:-main}" == "main" ]]; then
+      git -C "$TARGET" pull --ff-only
+    fi
+  elif [[ -e "$TARGET" ]]; then
+    echo "target exists but is not a symlink or git checkout: $TARGET" >&2
+    exit 1
+  else
+    echo "[open-source-sync] cloning updater checkout from explicit UPDATER_URL."
+    git clone "$UPDATER_URL" "$TARGET"
+    git -C "$TARGET" checkout "${UPDATER_REVISION:-main}"
   fi
-elif [[ -e "$TARGET" ]]; then
-  echo "target exists but is not a symlink or git checkout: $TARGET" >&2
-  exit 1
-elif is_git_checkout "$UPDATER_SRC"; then
-  rel_target="$(python3 - "$TARGET" "$UPDATER_SRC" <<'PY'
-import os
-import sys
-print(os.path.relpath(sys.argv[2], os.path.dirname(sys.argv[1])))
-PY
-)"
-  ln -s "$rel_target" "$TARGET"
-  echo "[open-source-sync] linked updater submodule into Flutter engine."
 else
-  echo "[open-source-sync] cloning public updater checkout."
+  echo "updater source checkout is missing: $UPDATER_SRC" >&2
-  git clone "$UPDATER_URL" "$TARGET"
+  echo "Set UPDATER_SRC to a local fork or set UPDATER_URL explicitly." >&2
-  git -C "$TARGET" checkout "${UPDATER_REVISION:-main}"
+  exit 1
 fi
 
 if [[ ! -f "$TARGET/library/include/updater_engine.h" ]]; then

scripts/validate_artifact_mirror.py

@@ -0,0 +1,210 @@
+#!/usr/bin/env python3
+"""Validate an assembled open Shorebird artifact mirror."""
+
+from __future__ import annotations
+
+import argparse
+import hashlib
+from pathlib import Path, PurePosixPath
+import re
+import sys
+import zipfile
+
+
+REQUIRED_PATCH_ZIPS = {
+    "patch-linux-x64.zip": "patch",
+    "patch-darwin-x64.zip": "patch",
+    "patch-darwin-arm64.zip": "patch",
+    "patch-windows-x64.zip": "patch.exe",
+}
+
+
+def digest_file(path: Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as file:
+        for chunk in iter(lambda: file.read(1024 * 1024), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def is_plain_file(path: Path) -> bool:
+    return path.is_file() and not path.is_symlink()
+
+
+def parse_sidecar(path: Path) -> tuple[str, str]:
+    text = path.read_text(encoding="utf-8").strip()
+    parts = text.split()
+    if len(parts) != 2:
+        raise ValueError(f"expected '<sha256>  <filename>', got {text!r}")
+    digest, filename = parts
+    if len(digest) != 64 or any(char not in "0123456789abcdef" for char in digest):
+        raise ValueError(f"invalid sha256 digest {digest!r}")
+    return digest, filename
+
+
+def is_safe_relative_path(path: str) -> bool:
+    if not path or path == ".":
+        return False
+    if "\\" in path or "\x00" in path or path.endswith("/"):
+        return False
+    if any(ord(character) < 32 for character in path):
+        return False
+
+    candidate = PurePosixPath(path)
+    if candidate.is_absolute():
+        return False
+    if any(part in ("", ".", "..") for part in candidate.parts):
+        return False
+    if candidate.parts and ":" in candidate.parts[0]:
+        return False
+    return True
+
+
+def validate_sidecars(shorebird_root: Path) -> list[str]:
+    errors: list[str] = []
+    for artifact_path in sorted(shorebird_root.rglob("*")):
+        if artifact_path.is_symlink():
+            errors.append(f"{artifact_path.relative_to(shorebird_root.parent)}: symlink entries are not allowed")
+            continue
+        if not artifact_path.is_file():
+            continue
+        if artifact_path.suffix == ".sha256":
+            artifact_path_without_suffix = Path(str(artifact_path)[: -len(".sha256")])
+            if not is_plain_file(artifact_path_without_suffix):
+                errors.append(f"{artifact_path.relative_to(shorebird_root.parent)}: orphan sidecar")
+            continue
+
+        sidecar_path = Path(f"{artifact_path}.sha256")
+        if not is_plain_file(sidecar_path):
+            errors.append(f"{artifact_path.relative_to(shorebird_root.parent)}: missing sidecar")
+            continue
+        try:
+            sidecar_digest, sidecar_filename = parse_sidecar(sidecar_path)
+        except ValueError as error:
+            errors.append(f"{sidecar_path.relative_to(shorebird_root.parent)}: {error}")
+            continue
+        actual_digest = digest_file(artifact_path)
+        if sidecar_digest != actual_digest:
+            errors.append(
+                f"{sidecar_path.relative_to(shorebird_root.parent)}: digest mismatch "
+                f"{sidecar_digest} != {actual_digest}"
+            )
+        if sidecar_filename != artifact_path.name:
+            errors.append(
+                f"{sidecar_path.relative_to(shorebird_root.parent)}: filename mismatch "
+                f"{sidecar_filename!r} != {artifact_path.name!r}"
+            )
+    return errors
+
+
+def validate_manifest_overrides(mirror_root: Path, manifest_paths: list[Path]) -> list[str]:
+    override_pattern = re.compile(r"^\s*-\s*'?(?P<path>[^'#\n]+?)'?\s*(?:#.*)?$")
+    shorebird_root = mirror_root / "shorebird"
+    errors: list[str] = []
+    for manifest_path in manifest_paths:
+        engine_revision = manifest_path.parent.name
+        for line in manifest_path.read_text(encoding="utf-8").splitlines():
+            match = override_pattern.match(line)
+            if not match:
+                continue
+            artifact_path = match.group("path").replace("$engine", engine_revision)
+            if not is_safe_relative_path(artifact_path):
+                errors.append(
+                    f"{manifest_path.relative_to(mirror_root)} -> "
+                    f"unsafe artifact override path: {artifact_path}"
+                )
+                continue
+            resolved_artifact_path = shorebird_root / artifact_path
+            if not is_plain_file(resolved_artifact_path):
+                errors.append(
+                    f"{manifest_path.relative_to(mirror_root)} -> shorebird/{artifact_path}"
+                )
+                continue
+            if resolved_artifact_path.stat().st_size <= 0:
+                errors.append(
+                    f"{manifest_path.relative_to(mirror_root)} -> "
+                    f"shorebird/{artifact_path}: artifact override is empty"
+                )
+    return errors
+
+
+def validate_patch_zips(mirror_root: Path, manifest_paths: list[Path]) -> list[str]:
+    errors: list[str] = []
+    for manifest_path in manifest_paths:
+        engine_dir = manifest_path.parent
+        for zip_name, expected_entry in REQUIRED_PATCH_ZIPS.items():
+            zip_path = engine_dir / zip_name
+            display_path = zip_path.relative_to(mirror_root)
+            if not is_plain_file(zip_path):
+                errors.append(f"{display_path}: missing")
+                continue
+            try:
+                with zipfile.ZipFile(zip_path) as archive:
+                    names = archive.namelist()
+                    if names != [expected_entry]:
+                        errors.append(
+                            f"{display_path}: expected only {expected_entry!r}, got {names!r}"
+                        )
+                        continue
+                    if archive.getinfo(expected_entry).file_size <= 0:
+                        errors.append(f"{display_path}: {expected_entry} is empty")
+            except zipfile.BadZipFile:
+                errors.append(f"{display_path}: invalid zip")
+    return errors
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("mirror_root", type=Path)
+    return parser.parse_args()
+
+
+def main() -> int:
+    args = parse_args()
+    mirror_root = args.mirror_root
+    shorebird_root = mirror_root / "shorebird"
+
+    if not mirror_root.is_dir():
+        print(f"missing mirror root: {mirror_root}", file=sys.stderr)
+        return 66
+    if not shorebird_root.is_dir():
+        print(f"mirror root is missing shorebird/: {mirror_root}", file=sys.stderr)
+        return 70
+
+    manifest_paths = sorted(shorebird_root.glob("*/artifacts_manifest.yaml"))
+    if not manifest_paths:
+        print(
+            "artifact mirror is missing shorebird/<engine>/artifacts_manifest.yaml",
+            file=sys.stderr,
+        )
+        return 70
+
+    errors: list[str] = []
+    sidecar_errors = validate_sidecars(shorebird_root)
+    if sidecar_errors:
+        errors.append("invalid checksum sidecars:\n" + "\n".join(f"  {e}" for e in sidecar_errors))
+
+    override_errors = validate_manifest_overrides(mirror_root, manifest_paths)
+    if override_errors:
+        errors.append(
+            "invalid files referenced by artifacts_manifest.yaml:\n"
+            + "\n".join(f"  {path}" for path in override_errors)
+        )
+
+    patch_errors = validate_patch_zips(mirror_root, manifest_paths)
+    if patch_errors:
+        errors.append(
+            "invalid CLI patch-tool artifacts:\n"
+            + "\n".join(f"  {error}" for error in patch_errors)
+        )
+
+    if errors:
+        print("artifact mirror validation failed:\n" + "\n".join(errors), file=sys.stderr)
+        return 70
+
+    print(f"artifact mirror validated: {mirror_root}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

scripts/validate_release_manifest.py

@@ -0,0 +1,249 @@
+#!/usr/bin/env python3
+"""Validate a JSON release manifest against downloaded CI artifacts."""
+
+from __future__ import annotations
+
+import argparse
+import hashlib
+import json
+from pathlib import Path, PurePosixPath
+import sys
+
+
+def digest_file(path: Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as file:
+        for chunk in iter(lambda: file.read(1024 * 1024), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def is_plain_file(path: Path) -> bool:
+    return path.is_file() and not path.is_symlink()
+
+
+def parse_sidecar(path: Path) -> tuple[str, str]:
+    text = path.read_text(encoding="utf-8").strip()
+    parts = text.split()
+    if len(parts) != 2:
+        raise ValueError(f"expected '<sha256>  <filename>', got {text!r}")
+    digest, filename = parts
+    if len(digest) != 64 or any(char not in "0123456789abcdef" for char in digest):
+        raise ValueError(f"invalid sha256 digest {digest!r}")
+    return digest, filename
+
+
+def is_safe_relative_path(path: str) -> bool:
+    if not path or path == ".":
+        return False
+    if "\\" in path or "\x00" in path or path.endswith("/"):
+        return False
+    if any(ord(character) < 32 for character in path):
+        return False
+
+    candidate = PurePosixPath(path)
+    if candidate.is_absolute():
+        return False
+    if any(part in ("", ".", "..") for part in candidate.parts):
+        return False
+    if candidate.parts and ":" in candidate.parts[0]:
+        return False
+    return True
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--github-sha",
+        default="",
+        help="Require the manifest github_sha field to match this commit SHA.",
+    )
+    parser.add_argument("input_dir", type=Path)
+    parser.add_argument("manifest", type=Path)
+    return parser.parse_args()
+
+
+def main() -> int:
+    args = parse_args()
+    input_dir = args.input_dir
+    manifest_path = args.manifest
+
+    if not input_dir.is_dir():
+        print(f"missing input directory: {input_dir}", file=sys.stderr)
+        return 66
+    if not manifest_path.is_file():
+        print(f"missing release manifest: {manifest_path}", file=sys.stderr)
+        return 66
+
+    try:
+        manifest = json.loads(manifest_path.read_text(encoding="utf-8"))
+    except json.JSONDecodeError as error:
+        print(f"invalid release manifest JSON: {error}", file=sys.stderr)
+        return 70
+
+    errors: list[str] = []
+    if manifest.get("format_version") != 1:
+        errors.append(f"format_version is {manifest.get('format_version')!r}; expected 1")
+    if not isinstance(manifest.get("github_sha", ""), str):
+        errors.append("github_sha must be a string")
+    elif args.github_sha and manifest.get("github_sha") != args.github_sha:
+        errors.append(
+            f"github_sha is {manifest.get('github_sha')!r}; expected {args.github_sha!r}"
+        )
+
+    artifacts = manifest.get("artifacts")
+    if not isinstance(artifacts, list):
+        errors.append("artifacts must be a list")
+        artifacts = []
+
+    expected_count = manifest.get("artifact_count")
+    if expected_count != len(artifacts):
+        errors.append(
+            f"artifact_count is {expected_count!r}; expected {len(artifacts)}"
+        )
+
+    seen_paths: set[str] = set()
+    seen_sidecars: set[str] = set()
+    for index, artifact in enumerate(artifacts):
+        if not isinstance(artifact, dict):
+            errors.append(f"artifacts[{index}] must be an object")
+            continue
+
+        artifact_path_text = artifact.get("path")
+        artifact_group = artifact.get("artifact_group")
+        filename = artifact.get("filename")
+        sidecar_path_text = artifact.get("sidecar")
+        expected_digest = artifact.get("sha256")
+        expected_size = artifact.get("size")
+        if not isinstance(artifact_path_text, str):
+            errors.append(f"artifacts[{index}].path must be a string")
+            continue
+        if artifact_path_text in seen_paths:
+            errors.append(f"{artifact_path_text}: duplicate artifact path")
+        seen_paths.add(artifact_path_text)
+        if not is_safe_relative_path(artifact_path_text):
+            errors.append(f"{artifact_path_text}: unsafe artifact path")
+            continue
+        artifact_relative = PurePosixPath(artifact_path_text)
+
+        if not isinstance(artifact_group, str):
+            errors.append(f"{artifact_path_text}: artifact_group must be a string")
+        elif artifact_group != artifact_relative.parts[0]:
+            errors.append(
+                f"{artifact_path_text}: artifact_group {artifact_group!r} "
+                f"does not match path group {artifact_relative.parts[0]!r}"
+            )
+
+        if not isinstance(filename, str):
+            errors.append(f"{artifact_path_text}: filename must be a string")
+        elif filename != artifact_relative.name:
+            errors.append(
+                f"{artifact_path_text}: filename {filename!r} "
+                f"does not match path filename {artifact_relative.name!r}"
+            )
+
+        if not isinstance(sidecar_path_text, str):
+            errors.append(f"{artifact_path_text}: sidecar must be a string")
+            continue
+        if sidecar_path_text in seen_sidecars:
+            errors.append(f"{sidecar_path_text}: duplicate sidecar path")
+        seen_sidecars.add(sidecar_path_text)
+        if not is_safe_relative_path(sidecar_path_text):
+            errors.append(f"{sidecar_path_text}: unsafe sidecar path")
+            continue
+
+        artifact_path = input_dir / artifact_path_text
+        sidecar_path = input_dir / sidecar_path_text
+        if not is_plain_file(artifact_path):
+            errors.append(f"{artifact_path_text}: missing artifact file")
+            continue
+        if not is_plain_file(sidecar_path):
+            errors.append(f"{sidecar_path_text}: missing sidecar file")
+            continue
+        actual_size = artifact_path.stat().st_size
+        if actual_size <= 0:
+            errors.append(f"{artifact_path_text}: empty artifacts are not allowed")
+        if sidecar_path != Path(f"{artifact_path}.sha256"):
+            errors.append(
+                f"{artifact_path_text}: sidecar path {sidecar_path_text!r} "
+                f"does not match sibling {artifact_path.name}.sha256"
+            )
+
+        actual_digest = digest_file(artifact_path)
+        if expected_digest != actual_digest:
+            errors.append(
+                f"{artifact_path_text}: digest mismatch "
+                f"{expected_digest!r} != {actual_digest}"
+            )
+        if expected_size != actual_size:
+            errors.append(
+                f"{artifact_path_text}: size mismatch "
+                f"{expected_size!r} != {actual_size}"
+            )
+
+        try:
+            sidecar_digest, sidecar_filename = parse_sidecar(sidecar_path)
+        except ValueError as error:
+            errors.append(f"{sidecar_path_text}: {error}")
+            continue
+        if sidecar_digest != actual_digest:
+            errors.append(
+                f"{sidecar_path_text}: sidecar digest mismatch "
+                f"{sidecar_digest} != {actual_digest}"
+            )
+        if sidecar_filename != artifact_path.name:
+            errors.append(
+                f"{sidecar_path_text}: sidecar filename mismatch "
+                f"{sidecar_filename!r} != {artifact_path.name!r}"
+            )
+
+    manifest_resolved = manifest_path.resolve()
+    manifest_sidecar_resolved = Path(f"{manifest_path}.sha256").resolve()
+    actual_artifacts: set[str] = set()
+    actual_sidecars: set[str] = set()
+    for path in sorted(input_dir.rglob("*")):
+        if not path.is_file():
+            continue
+        if path.is_symlink():
+            relative = path.relative_to(input_dir).as_posix()
+            if path.suffix == ".sha256":
+                actual_sidecars.add(relative)
+            else:
+                actual_artifacts.add(relative)
+            continue
+        resolved = path.resolve()
+        if resolved == manifest_resolved or resolved == manifest_sidecar_resolved:
+            continue
+        relative = path.relative_to(input_dir).as_posix()
+        if path.suffix == ".sha256":
+            actual_sidecars.add(relative)
+        else:
+            actual_artifacts.add(relative)
+
+    missing_from_manifest = sorted(actual_artifacts - seen_paths)
+    if missing_from_manifest:
+        errors.append(
+            "artifacts missing from release manifest: "
+            + ", ".join(missing_from_manifest)
+        )
+
+    orphan_sidecars = sorted(actual_sidecars - seen_sidecars)
+    if orphan_sidecars:
+        errors.append(
+            "sidecars missing from release manifest: " + ", ".join(orphan_sidecars)
+        )
+
+    if errors:
+        print(
+            "release manifest validation failed:\n"
+            + "\n".join(f"  {error}" for error in errors),
+            file=sys.stderr,
+        )
+        return 70
+
+    print(f"release manifest validated: {manifest_path}")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

scripts/verify_artifact_mirror_validator.sh

@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-mirror-validator.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+"$ROOT/scripts/verify_assemble_artifact_mirror.sh" >/dev/null
+
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+ENGINE_REVISION=engine123
+MIRROR_ROOT="$TMP_DIR/mirror"
+mkdir -p "$MIRROR_ROOT/shorebird/$ENGINE_REVISION"
+cat > "$MIRROR_ROOT/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml" <<EOF
+flutter_engine_revision: 'base-engine'
+storage_bucket: 'shorebird'
+artifact_overrides:
+  - 'flutter_infra_release/flutter/\$engine/linux-x64-release/artifacts.zip'
+EOF
+
+"$PYTHON_BIN" - "$MIRROR_ROOT/shorebird/$ENGINE_REVISION" <<'PY'
+from pathlib import Path
+import sys
+import zipfile
+
+root = Path(sys.argv[1])
+patch_zips = {
+    "patch-linux-x64.zip": "patch",
+    "patch-darwin-x64.zip": "patch",
+    "patch-darwin-arm64.zip": "patch",
+    "patch-windows-x64.zip": "patch.exe",
+}
+for zip_name, entry_name in patch_zips.items():
+    with zipfile.ZipFile(root / zip_name, "w", zipfile.ZIP_DEFLATED) as archive:
+        archive.writestr(entry_name, f"{zip_name}:{entry_name}\n")
+PY
+
+mkdir -p "$MIRROR_ROOT/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release"
+printf 'linux-engine-artifacts\n' \
+  > "$MIRROR_ROOT/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release/artifacts.zip"
+
+while IFS= read -r -d '' mirror_file; do
+  if [[ "$mirror_file" == *.sha256 ]]; then
+    continue
+  fi
+  "$ROOT/scripts/write_sha256.sh" "$mirror_file"
+done < <(find "$MIRROR_ROOT/shorebird" -type f -print0)
+
+"$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" "$MIRROR_ROOT" >/dev/null
+
+UNSAFE_MIRROR_ROOT="$TMP_DIR/unsafe-mirror"
+cp -R "$MIRROR_ROOT" "$UNSAFE_MIRROR_ROOT"
+"$PYTHON_BIN" - "$UNSAFE_MIRROR_ROOT/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml" <<'PY'
+from pathlib import Path
+import sys
+
+manifest_path = Path(sys.argv[1])
+manifest_path.write_text(
+    "\n".join(
+        [
+            "flutter_engine_revision: 'base-engine'",
+            "storage_bucket: 'shorebird'",
+            "artifact_overrides:",
+            "  - '../outside/artifacts.zip'",
+        ]
+    )
+    + "\n",
+    encoding="utf-8",
+)
+PY
+"$ROOT/scripts/write_sha256.sh" \
+  "$UNSAFE_MIRROR_ROOT/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml" \
+  "$UNSAFE_MIRROR_ROOT/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml.sha256"
+if "$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" \
+    "$UNSAFE_MIRROR_ROOT" >"$TMP_DIR/unsafe-mirror.log" 2>&1; then
+  echo "validate_artifact_mirror.py unexpectedly accepted an unsafe manifest override" >&2
+  exit 70
+fi
+grep -q "unsafe artifact override path" "$TMP_DIR/unsafe-mirror.log"
+
+SYMLINK_MIRROR_ROOT="$TMP_DIR/symlink-mirror"
+cp -R "$MIRROR_ROOT" "$SYMLINK_MIRROR_ROOT"
+rm "$SYMLINK_MIRROR_ROOT/shorebird/$ENGINE_REVISION/patch-linux-x64.zip"
+ln -s "$MIRROR_ROOT/shorebird/$ENGINE_REVISION/patch-linux-x64.zip" \
+  "$SYMLINK_MIRROR_ROOT/shorebird/$ENGINE_REVISION/patch-linux-x64.zip"
+if "$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" \
+    "$SYMLINK_MIRROR_ROOT" >"$TMP_DIR/symlink-mirror.log" 2>&1; then
+  echo "validate_artifact_mirror.py unexpectedly accepted a symlink artifact" >&2
+  exit 70
+fi
+grep -q "symlink entries are not allowed" "$TMP_DIR/symlink-mirror.log"
+
+EMPTY_OVERRIDE_ROOT="$TMP_DIR/empty-override-mirror"
+cp -R "$MIRROR_ROOT" "$EMPTY_OVERRIDE_ROOT"
+"$PYTHON_BIN" - "$EMPTY_OVERRIDE_ROOT/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release/artifacts.zip" <<'PY'
+from pathlib import Path
+import sys
+
+Path(sys.argv[1]).write_bytes(b"")
+PY
+"$ROOT/scripts/write_sha256.sh" \
+  "$EMPTY_OVERRIDE_ROOT/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release/artifacts.zip" \
+  "$EMPTY_OVERRIDE_ROOT/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release/artifacts.zip.sha256"
+if "$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" \
+    "$EMPTY_OVERRIDE_ROOT" >"$TMP_DIR/empty-override-mirror.log" 2>&1; then
+  echo "validate_artifact_mirror.py unexpectedly accepted an empty manifest override artifact" >&2
+  exit 70
+fi
+grep -q "artifact override is empty" "$TMP_DIR/empty-override-mirror.log"
+
+printf 'tampered\n' >> "$MIRROR_ROOT/shorebird/$ENGINE_REVISION/patch-linux-x64.zip"
+if "$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" "$MIRROR_ROOT" >/dev/null 2>&1; then
+  echo "validate_artifact_mirror.py unexpectedly accepted a stale sidecar" >&2
+  exit 70
+fi
+
+echo "validate_artifact_mirror.py smoke test passed"

scripts/verify_artifact_mirror_workflow_assembly.sh

@@ -0,0 +1,287 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-artifact-job.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+ENGINE_REVISION=engine123
+DOWNLOADED="$TMP_DIR/downloaded-artifacts"
+mkdir -p "$DOWNLOADED"
+
+write_artifact() {
+  local path="$1"
+  local content="$2"
+  mkdir -p "$(dirname "$path")"
+  printf '%s\n' "$content" > "$path"
+  "$ROOT/scripts/write_sha256.sh" "$path"
+}
+
+write_zip() {
+  local zip_path="$1"
+  local entry_name="$2"
+  local content="$3"
+  mkdir -p "$(dirname "$zip_path")"
+  "$PYTHON_BIN" - "$zip_path" "$entry_name" "$content" <<'PY'
+from pathlib import Path
+import sys
+import zipfile
+
+zip_path, entry_name, content = sys.argv[1:]
+with zipfile.ZipFile(Path(zip_path), "w", zipfile.ZIP_DEFLATED) as archive:
+    archive.writestr(entry_name, content + "\n")
+PY
+  "$ROOT/scripts/write_sha256.sh" "$zip_path"
+}
+
+write_tgz() {
+  local archive_path="$1"
+  local staging_dir="$2"
+  local root_entry="$3"
+  mkdir -p "$(dirname "$archive_path")"
+  tar -C "$staging_dir" -czf "$archive_path" "$root_entry"
+  "$ROOT/scripts/write_sha256.sh" "$archive_path"
+}
+
+for target in \
+  cli-linux-x64/open-shorebird-cli-linux-x64.tar.gz \
+  cli-macos-x64/open-shorebird-cli-macos-x64.tar.gz \
+  cli-macos-arm64/open-shorebird-cli-macos-arm64.tar.gz \
+  cli-windows-x64/open-shorebird-cli-windows-x64.tar.gz \
+  shorebird-server-linux-amd64/shorebird-server-linux-amd64.tar.gz \
+  shorebird-server-linux-arm64/shorebird-server-linux-arm64.tar.gz \
+  shorebird-server-darwin-amd64/shorebird-server-darwin-amd64.tar.gz \
+  shorebird-server-darwin-arm64/shorebird-server-darwin-arm64.tar.gz \
+  shorebird-server-windows-amd64/shorebird-server-windows-amd64.tar.gz \
+  custom-dart-sdk-linux-x64/custom-dart-sdk-linux-x64.tar.gz \
+  custom-dart-sdk-macos-arm64/custom-dart-sdk-macos-arm64.tar.gz; do
+  write_artifact "$DOWNLOADED/$target" "$target"
+done
+
+mkdir -p "$DOWNLOADED/mirror-metadata/$ENGINE_REVISION"
+cat > "$DOWNLOADED/mirror-metadata/$ENGINE_REVISION/artifacts_manifest.yaml" <<EOF
+flutter_engine_revision: 'base-engine'
+storage_bucket: 'shorebird'
+artifact_overrides:
+  - 'flutter_infra_release/flutter/\$engine/android-arm64-release/artifacts.zip'
+  - 'flutter_infra_release/flutter/\$engine/android-arm64-release/symbols.zip'
+  - 'flutter_infra_release/flutter/\$engine/linux-x64-release/artifacts.zip'
+  - 'flutter_infra_release/flutter/\$engine/linux-x64-release/linux-x64-flutter-gtk.zip'
+  - 'flutter_infra_release/flutter/\$engine/ios-release/artifacts.zip'
+  - 'flutter_infra_release/flutter/\$engine/flutter_patched_sdk_product.zip'
+  - 'flutter_infra_release/flutter/\$engine/flutter-web-sdk.zip'
+  - 'flutter_infra_release/flutter/\$engine/darwin-arm64-release/FlutterMacOS.framework.zip'
+EOF
+"$ROOT/scripts/write_sha256.sh" \
+  "$DOWNLOADED/mirror-metadata/$ENGINE_REVISION/artifacts_manifest.yaml"
+
+write_patch_artifact() {
+  local artifact_name="$1"
+  local zip_name="$2"
+  local entry_name="$3"
+  write_zip "$DOWNLOADED/$artifact_name/artifacts/mirror/$zip_name" "$entry_name" "$zip_name"
+  write_zip "$DOWNLOADED/$artifact_name/artifacts/mirror/shorebird/$ENGINE_REVISION/$zip_name" "$entry_name" "$zip_name"
+}
+write_patch_artifact mirror-patch-linux-x64.zip patch-linux-x64.zip patch
+write_patch_artifact mirror-patch-darwin-x64.zip patch-darwin-x64.zip patch
+write_patch_artifact mirror-patch-darwin-arm64.zip patch-darwin-arm64.zip patch
+write_patch_artifact mirror-patch-windows-x64.zip patch-windows-x64.zip patch.exe
+
+engine_stage="$TMP_DIR/engine-stage"
+mkdir -p "$engine_stage"
+
+make_engine_archive() {
+  local artifact_dir="$1"
+  local archive_name="$2"
+  local root_name="$3"
+  local mirror_subdir="$4"
+  shift 4
+
+  local stage="$engine_stage/$root_name"
+  rm -rf "$stage"
+  mkdir -p "$stage/$root_name/mirror/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/$mirror_subdir"
+  while [[ "$#" -gt 0 ]]; do
+    local file_name="$1"
+    local content="$2"
+    shift 2
+    write_artifact \
+      "$stage/$root_name/mirror/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/$mirror_subdir/$file_name" \
+      "$content"
+  done
+  write_tgz "$DOWNLOADED/$artifact_dir/$archive_name" "$stage" "$root_name"
+}
+
+make_engine_archive \
+  linux-engine-x64 linux-engine-x64.tar.gz linux-engine linux-x64-release \
+  artifacts.zip linux-artifacts \
+  linux-x64-flutter-gtk.zip linux-gtk
+mkdir -p "$engine_stage/linux-engine/linux-engine/mirror/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION"
+write_artifact \
+  "$engine_stage/linux-engine/linux-engine/mirror/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/flutter_patched_sdk_product.zip" \
+  linux-patched-sdk
+write_tgz "$DOWNLOADED/linux-engine-x64/linux-engine-x64.tar.gz" \
+  "$engine_stage/linux-engine" \
+  linux-engine
+
+make_engine_archive \
+  android-engine-arm64 android-engine-arm64.tar.gz android-engine android-arm64-release \
+  artifacts.zip android-artifacts \
+  symbols.zip android-symbols
+make_engine_archive \
+  flutter-web-sdk flutter-web-sdk.tar.gz web-sdk . \
+  flutter-web-sdk.zip web-sdk
+make_engine_archive \
+  ios-interpreter-engine ios-interpreter-engine.tar.gz ios-engine ios-release \
+  artifacts.zip ios-artifacts
+make_engine_archive \
+  macos-engine-arm64 macos-engine-arm64.tar.gz macos-engine darwin-arm64-release \
+  FlutterMacOS.framework.zip macos-framework
+
+mirror_input="$TMP_DIR/mirror-input"
+mkdir -p "$mirror_input"
+cp -R "$DOWNLOADED"/mirror-* "$mirror_input/"
+cp -R "$DOWNLOADED/linux-engine-x64" "$mirror_input/"
+cp -R "$DOWNLOADED/android-engine-arm64" "$mirror_input/"
+cp -R "$DOWNLOADED/flutter-web-sdk" "$mirror_input/"
+cp -R "$DOWNLOADED/ios-interpreter-engine" "$mirror_input/"
+cp -R "$DOWNLOADED/macos-engine-arm64" "$mirror_input/"
+
+assembled="$TMP_DIR/artifacts/open-shorebird-artifact-mirror"
+mkdir -p "$TMP_DIR/artifacts"
+"$ROOT/scripts/assemble_artifact_mirror.sh" "$mirror_input" "$assembled" >/dev/null
+tar -C "$TMP_DIR/artifacts" -czf "$TMP_DIR/open-shorebird-artifact-mirror.tar.gz" open-shorebird-artifact-mirror
+mirror_extract_dir="$TMP_DIR/mirror-extract"
+mkdir -p "$mirror_extract_dir"
+"$PYTHON_BIN" "$ROOT/scripts/safe_extract_tar.py" \
+  "$TMP_DIR/open-shorebird-artifact-mirror.tar.gz" \
+  "$mirror_extract_dir"
+"$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" \
+  "$mirror_extract_dir/open-shorebird-artifact-mirror" >/dev/null
+"$ROOT/scripts/write_sha256.sh" "$TMP_DIR/open-shorebird-artifact-mirror.tar.gz"
+
+manifest_input="$TMP_DIR/manifest-input"
+mkdir -p "$manifest_input"
+cp -R "$DOWNLOADED"/. "$manifest_input/"
+mkdir -p "$manifest_input/open-shorebird-artifact-mirror"
+cp "$TMP_DIR/open-shorebird-artifact-mirror.tar.gz" "$manifest_input/open-shorebird-artifact-mirror/"
+cp "$TMP_DIR/open-shorebird-artifact-mirror.tar.gz.sha256" "$manifest_input/open-shorebird-artifact-mirror/"
+
+"$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+  "$manifest_input" \
+  --github-sha test-sha \
+  --require 'cli-linux-x64/*open-shorebird-cli-linux-x64.tar.gz' \
+  --require 'cli-macos-x64/*open-shorebird-cli-macos-x64.tar.gz' \
+  --require 'cli-macos-arm64/*open-shorebird-cli-macos-arm64.tar.gz' \
+  --require 'cli-windows-x64/*open-shorebird-cli-windows-x64.tar.gz' \
+  --require 'shorebird-server-linux-amd64/*shorebird-server-linux-amd64.tar.gz' \
+  --require 'shorebird-server-linux-arm64/*shorebird-server-linux-arm64.tar.gz' \
+  --require 'shorebird-server-darwin-amd64/*shorebird-server-darwin-amd64.tar.gz' \
+  --require 'shorebird-server-darwin-arm64/*shorebird-server-darwin-arm64.tar.gz' \
+  --require 'shorebird-server-windows-amd64/*shorebird-server-windows-amd64.tar.gz' \
+  --require 'custom-dart-sdk-linux-x64/*custom-dart-sdk-linux-x64.tar.gz' \
+  --require 'custom-dart-sdk-macos-arm64/*custom-dart-sdk-macos-arm64.tar.gz' \
+  --require 'linux-engine-x64/*linux-engine-x64.tar.gz' \
+  --require 'android-engine-arm64/*android-engine-arm64.tar.gz' \
+  --require 'flutter-web-sdk/*flutter-web-sdk.tar.gz' \
+  --require 'ios-interpreter-engine/*ios-interpreter-engine.tar.gz' \
+  --require 'macos-engine-arm64/*macos-engine-arm64.tar.gz' \
+  --require 'mirror-patch-linux-x64.zip/*patch-linux-x64.zip' \
+  --require 'mirror-patch-darwin-x64.zip/*patch-darwin-x64.zip' \
+  --require 'mirror-patch-darwin-arm64.zip/*patch-darwin-arm64.zip' \
+  --require 'mirror-patch-windows-x64.zip/*patch-windows-x64.zip' \
+  --require 'mirror-metadata/*artifacts_manifest.yaml' \
+  --require 'open-shorebird-artifact-mirror/*open-shorebird-artifact-mirror.tar.gz' \
+  --output "$TMP_DIR/open-shorebird-release-manifest.json"
+
+"$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+  "$manifest_input" \
+  "$TMP_DIR/open-shorebird-release-manifest.json" >/dev/null
+
+mkdir -p "$manifest_input/open-shorebird-release-manifest"
+cp "$TMP_DIR/open-shorebird-release-manifest.json" \
+  "$manifest_input/open-shorebird-release-manifest/"
+"$ROOT/scripts/write_sha256.sh" \
+  "$manifest_input/open-shorebird-release-manifest/open-shorebird-release-manifest.json"
+"$ROOT/scripts/verify_downloaded_release_artifacts.sh" \
+  --github-sha test-sha \
+  "$manifest_input" >/dev/null
+if "$ROOT/scripts/verify_downloaded_release_artifacts.sh" \
+    --github-sha wrong-sha \
+    "$manifest_input" >"$TMP_DIR/wrong-download-sha.log" 2>&1; then
+  echo "unexpectedly accepted downloaded artifacts for the wrong github_sha" >&2
+  exit 1
+fi
+grep -q "github_sha is" "$TMP_DIR/wrong-download-sha.log"
+
+release_manifest_path="$manifest_input/open-shorebird-release-manifest/open-shorebird-release-manifest.json"
+mirror_archive_path="$manifest_input/open-shorebird-artifact-mirror/open-shorebird-artifact-mirror.tar.gz"
+printf '%064d  open-shorebird-release-manifest.json\n' 0 > "$release_manifest_path.sha256"
+if "$ROOT/scripts/verify_downloaded_release_artifacts.sh" \
+    --github-sha test-sha \
+    "$manifest_input" >/dev/null 2>&1; then
+  echo "unexpectedly accepted a stale downloaded release manifest sidecar" >&2
+  exit 1
+fi
+"$ROOT/scripts/write_sha256.sh" "$release_manifest_path"
+
+printf '%064d  open-shorebird-artifact-mirror.tar.gz\n' 0 > "$mirror_archive_path.sha256"
+if "$ROOT/scripts/verify_downloaded_release_artifacts.sh" \
+    --github-sha test-sha \
+    "$manifest_input" >/dev/null 2>&1; then
+  echo "unexpectedly accepted a stale downloaded mirror archive sidecar" >&2
+  exit 1
+fi
+"$ROOT/scripts/write_sha256.sh" "$mirror_archive_path"
+"$ROOT/scripts/verify_downloaded_release_artifacts.sh" \
+  --github-sha test-sha \
+  "$manifest_input" >/dev/null
+
+unsafe_download="$TMP_DIR/unsafe-download"
+cp -R "$manifest_input" "$unsafe_download"
+unsafe_mirror_archive="$unsafe_download/open-shorebird-artifact-mirror/open-shorebird-artifact-mirror.tar.gz"
+"$PYTHON_BIN" - "$unsafe_mirror_archive" <<'PY'
+import io
+import sys
+import tarfile
+
+archive_path = sys.argv[1]
+with tarfile.open(archive_path, "w:gz") as archive:
+    content = b"unsafe\n"
+    member = tarfile.TarInfo("../outside.txt")
+    member.size = len(content)
+    archive.addfile(member, io.BytesIO(content))
+PY
+"$ROOT/scripts/write_sha256.sh" "$unsafe_mirror_archive"
+"$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+  "$unsafe_download" \
+  --github-sha test-sha \
+  --require 'open-shorebird-artifact-mirror/*open-shorebird-artifact-mirror.tar.gz' \
+  --output "$unsafe_download/open-shorebird-release-manifest/open-shorebird-release-manifest.json"
+"$ROOT/scripts/write_sha256.sh" \
+  "$unsafe_download/open-shorebird-release-manifest/open-shorebird-release-manifest.json"
+if "$ROOT/scripts/verify_downloaded_release_artifacts.sh" \
+    --github-sha test-sha \
+    "$unsafe_download" >"$TMP_DIR/unsafe-download.log" 2>&1; then
+  echo "unexpectedly accepted an unsafe downloaded mirror archive" >&2
+  exit 1
+fi
+grep -q "unsafe archive member path" "$TMP_DIR/unsafe-download.log"
+
+"$PYTHON_BIN" - "$TMP_DIR/open-shorebird-release-manifest.json" <<'PY'
+import json
+import sys
+
+manifest = json.load(open(sys.argv[1], encoding="utf-8"))
+paths = {artifact["path"] for artifact in manifest["artifacts"]}
+assert any(path.endswith("open-shorebird-artifact-mirror.tar.gz") for path in paths)
+assert any(path.endswith("linux-engine-x64.tar.gz") for path in paths)
+assert any(path.endswith("patch-windows-x64.zip") for path in paths)
+assert any(path.endswith("artifacts_manifest.yaml") for path in paths)
+PY
+
+echo "artifact-mirror workflow assembly smoke test passed"

scripts/verify_assemble_artifact_mirror.sh

@@ -0,0 +1,180 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-assemble.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+ENGINE_REVISION=engine123
+INPUT_DIR="$TMP_DIR/downloaded-artifacts"
+OUTPUT_DIR="$TMP_DIR/mirror"
+mkdir -p "$INPUT_DIR"
+
+mkdir -p "$INPUT_DIR/mirror-metadata/$ENGINE_REVISION"
+cat > "$INPUT_DIR/mirror-metadata/$ENGINE_REVISION/artifacts_manifest.yaml" <<EOF
+flutter_engine_revision: 'base-engine'
+storage_bucket: 'shorebird'
+artifact_overrides:
+  - 'flutter_infra_release/flutter/\$engine/linux-x64-release/artifacts.zip'
+EOF
+"$ROOT/scripts/write_sha256.sh" \
+  "$INPUT_DIR/mirror-metadata/$ENGINE_REVISION/artifacts_manifest.yaml"
+
+mkdir -p "$INPUT_DIR/mirror-patch/artifacts/mirror/shorebird/$ENGINE_REVISION"
+"$PYTHON_BIN" - "$INPUT_DIR/mirror-patch/artifacts/mirror/shorebird/$ENGINE_REVISION" <<'PY'
+from pathlib import Path
+import sys
+import zipfile
+
+root = Path(sys.argv[1])
+patch_zips = {
+    "patch-linux-x64.zip": "patch",
+    "patch-darwin-x64.zip": "patch",
+    "patch-darwin-arm64.zip": "patch",
+    "patch-windows-x64.zip": "patch.exe",
+}
+for zip_name, entry_name in patch_zips.items():
+    with zipfile.ZipFile(root / zip_name, "w", zipfile.ZIP_DEFLATED) as archive:
+        archive.writestr(entry_name, f"{zip_name}:{entry_name}\n")
+PY
+
+engine_staging="$TMP_DIR/linux-engine"
+mkdir -p "$engine_staging/linux-engine/mirror/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release"
+printf 'linux-engine-artifacts\n' \
+  > "$engine_staging/linux-engine/mirror/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release/artifacts.zip"
+tar -C "$engine_staging" -czf "$INPUT_DIR/linux-engine-x64.tar.gz" linux-engine
+
+"$ROOT/scripts/assemble_artifact_mirror.sh" "$INPUT_DIR" "$OUTPUT_DIR"
+
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml.sha256"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-linux-x64.zip"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-linux-x64.zip.sha256"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-darwin-x64.zip"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-darwin-x64.zip.sha256"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-darwin-arm64.zip"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-darwin-arm64.zip.sha256"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-windows-x64.zip"
+test -f "$OUTPUT_DIR/shorebird/$ENGINE_REVISION/patch-windows-x64.zip.sha256"
+test -f "$OUTPUT_DIR/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release/artifacts.zip"
+test -f "$OUTPUT_DIR/shorebird/flutter_infra_release/flutter/$ENGINE_REVISION/linux-x64-release/artifacts.zip.sha256"
+
+CONFLICT_INPUT="$TMP_DIR/conflicting-artifacts"
+mkdir -p "$CONFLICT_INPUT/conflict/artifacts/mirror/shorebird/$ENGINE_REVISION"
+"$PYTHON_BIN" - "$CONFLICT_INPUT/conflict/artifacts/mirror/shorebird/$ENGINE_REVISION/patch-linux-x64.zip" <<'PY'
+from pathlib import Path
+import sys
+import zipfile
+
+with zipfile.ZipFile(Path(sys.argv[1]), "w", zipfile.ZIP_DEFLATED) as archive:
+    archive.writestr("patch", "different-patch\n")
+PY
+
+if "$ROOT/scripts/assemble_artifact_mirror.sh" "$CONFLICT_INPUT" "$OUTPUT_DIR" >/dev/null 2>&1; then
+  echo "assemble_artifact_mirror.sh unexpectedly allowed a conflicting mirror file" >&2
+  exit 70
+fi
+
+UNSAFE_TAR_INPUT="$TMP_DIR/unsafe-tar"
+UNSAFE_TAR_OUTPUT="$TMP_DIR/unsafe-tar-output"
+mkdir -p "$UNSAFE_TAR_INPUT"
+"$PYTHON_BIN" - "$UNSAFE_TAR_INPUT/unsafe-engine.tar.gz" <<'PY'
+import io
+import sys
+import tarfile
+
+archive_path = sys.argv[1]
+with tarfile.open(archive_path, "w:gz") as archive:
+    content = b"unsafe\n"
+    member = tarfile.TarInfo("../outside.txt")
+    member.size = len(content)
+    archive.addfile(member, io.BytesIO(content))
+PY
+if "$ROOT/scripts/assemble_artifact_mirror.sh" \
+    "$UNSAFE_TAR_INPUT" \
+    "$UNSAFE_TAR_OUTPUT" >"$TMP_DIR/unsafe-tar.log" 2>&1; then
+  echo "assemble_artifact_mirror.sh unexpectedly allowed an unsafe tar member" >&2
+  exit 70
+fi
+grep -q "unsafe archive member path" "$TMP_DIR/unsafe-tar.log"
+
+SYMLINK_TAR_INPUT="$TMP_DIR/symlink-tar"
+SYMLINK_TAR_OUTPUT="$TMP_DIR/symlink-tar-output"
+mkdir -p "$SYMLINK_TAR_INPUT"
+"$PYTHON_BIN" - "$SYMLINK_TAR_INPUT/symlink-engine.tar.gz" <<'PY'
+import sys
+import tarfile
+
+archive_path = sys.argv[1]
+with tarfile.open(archive_path, "w:gz") as archive:
+    member = tarfile.TarInfo("engine/mirror/shorebird/link")
+    member.type = tarfile.SYMTYPE
+    member.linkname = "/tmp/outside"
+    archive.addfile(member)
+PY
+if "$ROOT/scripts/assemble_artifact_mirror.sh" \
+    "$SYMLINK_TAR_INPUT" \
+    "$SYMLINK_TAR_OUTPUT" >"$TMP_DIR/symlink-tar.log" 2>&1; then
+  echo "assemble_artifact_mirror.sh unexpectedly allowed a tar symlink member" >&2
+  exit 70
+fi
+grep -q "unsupported archive member type" "$TMP_DIR/symlink-tar.log"
+
+DUPLICATE_TAR_INPUT="$TMP_DIR/duplicate-tar"
+DUPLICATE_TAR_OUTPUT="$TMP_DIR/duplicate-tar-output"
+mkdir -p "$DUPLICATE_TAR_INPUT"
+"$PYTHON_BIN" - "$DUPLICATE_TAR_INPUT/duplicate-engine.tar.gz" <<'PY'
+import io
+import sys
+import tarfile
+
+archive_path = sys.argv[1]
+with tarfile.open(archive_path, "w:gz") as archive:
+    for content in (b"first\n", b"second\n"):
+        member = tarfile.TarInfo("engine/mirror/shorebird/duplicate.txt")
+        member.size = len(content)
+        archive.addfile(member, io.BytesIO(content))
+PY
+if "$ROOT/scripts/assemble_artifact_mirror.sh" \
+    "$DUPLICATE_TAR_INPUT" \
+    "$DUPLICATE_TAR_OUTPUT" >"$TMP_DIR/duplicate-tar.log" 2>&1; then
+  echo "assemble_artifact_mirror.sh unexpectedly allowed a duplicate tar member" >&2
+  exit 70
+fi
+grep -q "duplicate archive member path" "$TMP_DIR/duplicate-tar.log"
+
+BAD_ZIP_INPUT="$TMP_DIR/bad-zip"
+BAD_ZIP_OUTPUT="$TMP_DIR/bad-zip-output"
+mkdir -p "$BAD_ZIP_INPUT/metadata/artifacts/mirror/shorebird/$ENGINE_REVISION"
+cat > "$BAD_ZIP_INPUT/metadata/artifacts/mirror/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml" <<EOF
+flutter_engine_revision: 'base-engine'
+storage_bucket: 'shorebird'
+artifact_overrides: []
+EOF
+printf 'not a zip\n' > "$BAD_ZIP_INPUT/metadata/artifacts/mirror/shorebird/$ENGINE_REVISION/patch-linux-x64.zip"
+
+if "$ROOT/scripts/assemble_artifact_mirror.sh" "$BAD_ZIP_INPUT" "$BAD_ZIP_OUTPUT" >/dev/null 2>&1; then
+  echo "assemble_artifact_mirror.sh unexpectedly allowed an invalid patch zip" >&2
+  exit 70
+fi
+
+MISSING_INPUT="$TMP_DIR/missing-override"
+MISSING_OUTPUT="$TMP_DIR/missing-output"
+mkdir -p "$MISSING_INPUT/metadata/artifacts/mirror/shorebird/$ENGINE_REVISION"
+cat > "$MISSING_INPUT/metadata/artifacts/mirror/shorebird/$ENGINE_REVISION/artifacts_manifest.yaml" <<EOF
+flutter_engine_revision: 'base-engine'
+storage_bucket: 'shorebird'
+artifact_overrides:
+  - 'flutter_infra_release/flutter/\$engine/ios-release/artifacts.zip'
+EOF
+
+if "$ROOT/scripts/assemble_artifact_mirror.sh" "$MISSING_INPUT" "$MISSING_OUTPUT" >/dev/null 2>&1; then
+  echo "assemble_artifact_mirror.sh unexpectedly allowed a missing manifest override" >&2
+  exit 70
+fi
+
+echo "assemble_artifact_mirror.sh smoke test passed"

scripts/verify_ci_capacity.sh

@@ -0,0 +1,26 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+CI_MIN_FREE_DISK_GB=2 \
+  CI_AVAILABLE_DISK_KB_OVERRIDE=$((3 * 1024 * 1024)) \
+  "$ROOT/scripts/check_ci_capacity.sh" >/dev/null
+
+if CI_MIN_FREE_DISK_GB=4 \
+    CI_AVAILABLE_DISK_KB_OVERRIDE=$((3 * 1024 * 1024)) \
+    "$ROOT/scripts/check_ci_capacity.sh" >/dev/null 2>&1; then
+  echo "check_ci_capacity.sh unexpectedly accepted insufficient disk" >&2
+  exit 70
+fi
+
+if CI_MIN_FREE_DISK_GB=not-a-number \
+    CI_AVAILABLE_DISK_KB_OVERRIDE=$((3 * 1024 * 1024)) \
+    "$ROOT/scripts/check_ci_capacity.sh" >/dev/null 2>&1; then
+  echo "check_ci_capacity.sh unexpectedly accepted an invalid minimum" >&2
+  exit 70
+fi
+
+CI_MIN_FREE_DISK_GB=0 "$ROOT/scripts/check_ci_capacity.sh" >/dev/null
+
+echo "check_ci_capacity.sh smoke test passed"

scripts/verify_ci_workflow.sh

@@ -0,0 +1,59 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+WORKFLOW="$ROOT/.github/workflows/open-shorebird-ci.yml"
+RUBY_ARGS=()
+
+usage() {
+  cat >&2 <<'EOF'
+usage: verify_ci_workflow.sh [--require-tracked] [--require-clean] [--require-upload-ready] [workflow.yml]
+
+Validates the Open Shorebird GitHub Actions workflow contract. The upload-ready
+mode additionally requires every required CI support file to be tracked in its
+own git checkout and every required owning checkout to be clean.
+EOF
+}
+
+while [[ "$#" -gt 0 ]]; do
+  case "$1" in
+    --require-tracked|--require-clean|--require-upload-ready)
+      RUBY_ARGS+=("$1")
+      shift
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    -*)
+      echo "unknown argument: $1" >&2
+      usage
+      exit 64
+      ;;
+    *)
+      WORKFLOW="$1"
+      shift
+      if [[ "$#" -gt 0 ]]; then
+        echo "unexpected extra argument: $1" >&2
+        usage
+        exit 64
+      fi
+      ;;
+  esac
+done
+
+if [[ ! -f "$WORKFLOW" ]]; then
+  echo "missing workflow: $WORKFLOW" >&2
+  exit 66
+fi
+
+command -v ruby >/dev/null 2>&1 || {
+  echo "ruby is required to validate GitHub workflow YAML" >&2
+  exit 127
+}
+
+if [[ "${#RUBY_ARGS[@]}" -eq 0 ]]; then
+  ruby "$ROOT/scripts/verify_ci_workflow.rb" "$WORKFLOW"
+else
+  ruby "$ROOT/scripts/verify_ci_workflow.rb" "${RUBY_ARGS[@]}" "$WORKFLOW"
+fi

scripts/verify_dart_sdk_args.sh

@@ -0,0 +1,60 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ "$#" -eq 0 ]]; then
+  echo "usage: $0 <args.gn>..." >&2
+  exit 64
+fi
+
+require_gn_value() {
+  local args_file="$1"
+  local key="$2"
+  local value="$3"
+  local actual
+
+  if ! actual="$(read_gn_value "$args_file" "$key")"; then
+    echo "expected $key = $value in $args_file, but $key is missing" >&2
+    exit 70
+  fi
+  if [[ "$actual" != "$value" ]]; then
+    echo "expected $key = $value in $args_file, found $actual" >&2
+    exit 70
+  fi
+}
+
+read_gn_value() {
+  local file="$1"
+  local key="$2"
+  awk -v key="$key" '
+    $1 == key && $2 == "=" {
+      value = $0
+      sub("^[[:space:]]*" key "[[:space:]]*=[[:space:]]*", "", value)
+      sub("[[:space:]]*$", "", value)
+      found = 1
+    }
+    END {
+      if (!found) {
+        exit 1
+      }
+      print value
+    }
+  ' "$file"
+}
+
+for args_file in "$@"; do
+  if [[ ! -f "$args_file" ]]; then
+    echo "missing args.gn: $args_file" >&2
+    exit 66
+  fi
+
+  if [[ "$(read_gn_value "$args_file" dart_dynamic_modules)" == "true" ]]; then
+    echo "DART_DYNAMIC_MODULES must not be enabled: $args_file" >&2
+    exit 70
+  fi
+
+  require_gn_value "$args_file" dart_dynamic_modules false
+  require_gn_value "$args_file" dart_enable_aot_patching true
+  require_gn_value "$args_file" dart_enable_shorebird_interpreter true
+
+  echo "Verified $args_file: patched Dart SDK flags are enabled without DDM"
+done

scripts/verify_dart_tool_sdk.sh

@@ -0,0 +1,45 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+DART_SRC="${DART_SRC:-$ROOT/dart-sdk}"
+TOOL_SDK="$DART_SRC/tools/sdks/dart-sdk"
+ENGINE_DART="$ROOT/flutter/engine/src/flutter/third_party/dart"
+
+required_constraint="$(
+  ruby -ryaml -e 'puts YAML.load_file(ARGV[0]).fetch("environment").fetch("sdk")' \
+    "$DART_SRC/pkg/front_end/pubspec.yaml"
+)"
+required_major_minor="$(
+  ruby -e 'ARGV[0] =~ /([0-9]+)\.([0-9]+)/ or abort "unable to parse SDK constraint"; puts "#{$1}.#{$2}"' \
+    "$required_constraint"
+)"
+
+if [[ ! -x "$TOOL_SDK/bin/dart" ]]; then
+  echo "missing executable Dart tool SDK: $TOOL_SDK/bin/dart" >&2
+  exit 66
+fi
+
+version_output="$("$TOOL_SDK/bin/dart" --version 2>&1)"
+actual_major_minor="$(
+  ruby -e 'ARGV[0] =~ /Dart SDK version: ([0-9]+)\.([0-9]+)/ or abort "unable to parse Dart version"; puts "#{$1}.#{$2}"' \
+    "$version_output"
+)"
+
+if [[ "$actual_major_minor" != "$required_major_minor" ]]; then
+  echo "Dart tool SDK version does not satisfy front_end SDK constraint." >&2
+  echo "  required major.minor: $required_major_minor from $required_constraint" >&2
+  echo "  actual: $version_output" >&2
+  exit 70
+fi
+
+if [[ -e "$ENGINE_DART" ]]; then
+  engine_real="$(python3 -c 'import os, sys; print(os.path.realpath(sys.argv[1]))' "$ENGINE_DART")"
+  dart_real="$(python3 -c 'import os, sys; print(os.path.realpath(sys.argv[1]))' "$DART_SRC")"
+  if [[ "$engine_real" != "$dart_real" ]]; then
+    echo "Flutter engine Dart checkout points at $engine_real, expected $dart_real" >&2
+    exit 70
+  fi
+fi
+
+echo "[open-source-sync] Dart tool SDK is compatible: $version_output"

scripts/verify_downloaded_release_artifacts.sh

@@ -0,0 +1,169 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+usage() {
+  cat >&2 <<'EOF'
+usage: verify_downloaded_release_artifacts.sh [--github-sha sha] downloaded-artifacts
+
+Verifies a downloaded full SDK build artifact set. The release manifest and
+artifact mirror archive must have valid checksum sidecars, the manifest must
+cover every downloaded artifact, and the mirror archive must safely extract to a
+valid open Shorebird artifact mirror.
+EOF
+}
+
+DOWNLOAD_DIR=""
+EXPECTED_GITHUB_SHA=""
+while [[ "$#" -gt 0 ]]; do
+  case "$1" in
+    --github-sha)
+      if [[ "$#" -lt 2 || -z "${2:-}" ]]; then
+        echo "--github-sha value is required" >&2
+        usage
+        exit 64
+      fi
+      EXPECTED_GITHUB_SHA="${2:-}"
+      shift 2
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    -*)
+      echo "unknown argument: $1" >&2
+      usage
+      exit 64
+      ;;
+    *)
+      if [[ -n "$DOWNLOAD_DIR" ]]; then
+        echo "unexpected extra argument: $1" >&2
+        usage
+        exit 64
+      fi
+      DOWNLOAD_DIR="$1"
+      shift
+      ;;
+  esac
+done
+
+if [[ -z "$DOWNLOAD_DIR" ]]; then
+  usage
+  exit 64
+fi
+
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-downloaded-release.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+fail() {
+  echo "error: $*" >&2
+  exit 70
+}
+
+verify_sha256_sidecar() {
+  local artifact_path="$1"
+  local sidecar_path="$2"
+
+  [[ -f "$sidecar_path" ]] || fail "missing checksum sidecar: $sidecar_path"
+
+  "$PYTHON_BIN" - "$artifact_path" "$sidecar_path" <<'PY'
+import hashlib
+from pathlib import Path
+import sys
+
+artifact_path = Path(sys.argv[1])
+sidecar_path = Path(sys.argv[2])
+
+try:
+    text = sidecar_path.read_text(encoding="utf-8").strip()
+except UnicodeDecodeError as error:
+    print(f"error: {sidecar_path}: invalid UTF-8: {error}", file=sys.stderr)
+    sys.exit(70)
+
+parts = text.split()
+if len(parts) != 2:
+    print(
+        f"error: {sidecar_path}: expected '<sha256>  <filename>', got {text!r}",
+        file=sys.stderr,
+    )
+    sys.exit(70)
+
+expected_digest, expected_filename = parts
+if len(expected_digest) != 64 or any(
+    char not in "0123456789abcdef" for char in expected_digest
+):
+    print(f"error: {sidecar_path}: invalid sha256 digest {expected_digest!r}", file=sys.stderr)
+    sys.exit(70)
+
+if expected_filename != artifact_path.name:
+    print(
+        f"error: {sidecar_path}: filename mismatch "
+        f"{expected_filename!r} != {artifact_path.name!r}",
+        file=sys.stderr,
+    )
+    sys.exit(70)
+
+digest = hashlib.sha256()
+with artifact_path.open("rb") as artifact:
+    for chunk in iter(lambda: artifact.read(1024 * 1024), b""):
+        digest.update(chunk)
+
+actual_digest = digest.hexdigest()
+if expected_digest != actual_digest:
+    print(
+        f"error: {sidecar_path}: digest mismatch "
+        f"{expected_digest} != {actual_digest}",
+        file=sys.stderr,
+    )
+    sys.exit(70)
+PY
+}
+
+[[ -d "$DOWNLOAD_DIR" ]] || fail "missing downloaded artifacts directory: $DOWNLOAD_DIR"
+
+manifest_paths=()
+while IFS= read -r path; do
+  manifest_paths+=("$path")
+done < <(find "$DOWNLOAD_DIR" -type f -name open-shorebird-release-manifest.json | sort)
+if [[ "${#manifest_paths[@]}" -ne 1 ]]; then
+  fail "expected exactly one open-shorebird-release-manifest.json, found ${#manifest_paths[@]}"
+fi
+manifest_path="${manifest_paths[0]}"
+manifest_sidecar="$manifest_path.sha256"
+
+verify_sha256_sidecar "$manifest_path" "$manifest_sidecar"
+
+validate_manifest_args=()
+if [[ -n "$EXPECTED_GITHUB_SHA" ]]; then
+  validate_manifest_args+=(--github-sha "$EXPECTED_GITHUB_SHA")
+fi
+"$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+  "${validate_manifest_args[@]}" \
+  "$DOWNLOAD_DIR" \
+  "$manifest_path"
+
+mirror_archives=()
+while IFS= read -r path; do
+  mirror_archives+=("$path")
+done < <(find "$DOWNLOAD_DIR" -type f -name open-shorebird-artifact-mirror.tar.gz | sort)
+if [[ "${#mirror_archives[@]}" -ne 1 ]]; then
+  fail "expected exactly one open-shorebird-artifact-mirror.tar.gz, found ${#mirror_archives[@]}"
+fi
+mirror_archive="${mirror_archives[0]}"
+
+mirror_sidecar="$mirror_archive.sha256"
+verify_sha256_sidecar "$mirror_archive" "$mirror_sidecar"
+
+"$PYTHON_BIN" "$ROOT/scripts/safe_extract_tar.py" "$mirror_archive" "$TMP_DIR"
+mirror_root="$TMP_DIR/open-shorebird-artifact-mirror"
+[[ -d "$mirror_root" ]] || fail "mirror archive did not contain open-shorebird-artifact-mirror/"
+
+"$PYTHON_BIN" "$ROOT/scripts/validate_artifact_mirror.py" "$mirror_root"
+
+echo "downloaded release artifacts verified: $DOWNLOAD_DIR"

scripts/verify_engine_args.sh

@@ -0,0 +1,84 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ "$#" -eq 0 ]]; then
+  echo "usage: $0 <args.gn>... | <args.gn> key=value ..." >&2
+  exit 64
+fi
+
+verify_no_ddm() {
+  local args_file="$1"
+
+  if [[ ! -f "$args_file" ]]; then
+    echo "missing args.gn: $args_file" >&2
+    exit 66
+  fi
+
+  local actual
+  if ! actual="$(read_gn_value "$args_file" dart_dynamic_modules)"; then
+    return 0
+  fi
+  if [[ "$actual" == "true" ]]; then
+    echo "DART_DYNAMIC_MODULES must not be enabled: $args_file" >&2
+    exit 70
+  fi
+}
+
+read_gn_value() {
+  local file="$1"
+  local key="$2"
+  awk -v key="$key" '
+    $1 == key && $2 == "=" {
+      value = $0
+      sub("^[[:space:]]*" key "[[:space:]]*=[[:space:]]*", "", value)
+      sub("[[:space:]]*$", "", value)
+      found = 1
+    }
+    END {
+      if (!found) {
+        exit 1
+      }
+      print value
+    }
+  ' "$file"
+}
+
+has_expectations=0
+for arg in "$@"; do
+  if [[ "$arg" == *=* ]]; then
+    has_expectations=1
+    break
+  fi
+done
+
+if [[ "$has_expectations" == "0" ]]; then
+  for args_file in "$@"; do
+    verify_no_ddm "$args_file"
+    echo "Verified $args_file: dart_dynamic_modules is not true"
+  done
+  exit 0
+fi
+
+args_file="$1"
+shift
+verify_no_ddm "$args_file"
+
+for expectation in "$@"; do
+  if [[ "$expectation" != *=* ]]; then
+    echo "invalid expectation: $expectation; expected key=value" >&2
+    exit 64
+  fi
+
+  key="${expectation%%=*}"
+  value="${expectation#*=}"
+  if ! actual="$(read_gn_value "$args_file" "$key")"; then
+    echo "expected $key = $value in $args_file, but $key is missing" >&2
+    exit 70
+  fi
+  if [[ "$actual" != "$value" ]]; then
+    echo "expected $key = $value in $args_file, found $actual" >&2
+    exit 70
+  fi
+done
+
+echo "Verified $args_file: dart_dynamic_modules is not true and expected flags are present"

scripts/verify_hosted_full_sdk_build.sh

@@ -0,0 +1,381 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+usage() {
+  cat >&2 <<'EOF'
+usage: verify_hosted_full_sdk_build.sh --repo owner/name [options]
+
+Dispatches the Open Shorebird full SDK build on GitHub Actions, waits for the
+workflow run to finish, downloads all artifacts, and verifies the release
+manifest plus assembled artifact mirror.
+
+Uses GitHub CLI when `gh` is available. Otherwise uses the GitHub REST API with
+`GITHUB_TOKEN` or `GH_TOKEN`; that fallback also requires `curl`, `jq`, and
+`unzip`.
+
+Options:
+  --repo owner/name                 GitHub repository to run against.
+  --ref branch-or-sha               Ref to dispatch. Defaults to current branch.
+  --workflow file                   Workflow file. Defaults to open-shorebird-ci.yml.
+  --download-dir path               Artifact download directory. Defaults to hosted-full-sdk-artifacts.
+  --timeout-minutes minutes         Maximum wait time. Defaults to 720.
+  --poll-seconds seconds            Poll interval. Defaults to 30.
+  --linux-heavy-runner label        Override linux_heavy_runner.
+  --macos-heavy-runner label        Override macos_heavy_runner.
+  --sdk-min-free-disk-gb value      Override sdk_min_free_disk_gb.
+  --engine-min-free-disk-gb value   Override engine_min_free_disk_gb.
+  --base-flutter-engine-revision v  Override base_flutter_engine_revision.
+  --skip-gclient-sync               Dispatch with run_gclient_sync=false.
+EOF
+}
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+REPO=""
+REF=""
+WORKFLOW="open-shorebird-ci.yml"
+DOWNLOAD_DIR="hosted-full-sdk-artifacts"
+TIMEOUT_MINUTES=720
+POLL_SECONDS=30
+LINUX_HEAVY_RUNNER=""
+MACOS_HEAVY_RUNNER=""
+SDK_MIN_FREE_DISK_GB=""
+ENGINE_MIN_FREE_DISK_GB=""
+BASE_FLUTTER_ENGINE_REVISION=""
+RUN_GCLIENT_SYNC=true
+GITHUB_API_URL="${GITHUB_API_URL:-https://api.github.com}"
+
+while [[ "$#" -gt 0 ]]; do
+  case "$1" in
+    --repo)
+      REPO="${2:-}"
+      shift 2
+      ;;
+    --ref)
+      REF="${2:-}"
+      shift 2
+      ;;
+    --workflow)
+      WORKFLOW="${2:-}"
+      shift 2
+      ;;
+    --download-dir)
+      DOWNLOAD_DIR="${2:-}"
+      shift 2
+      ;;
+    --timeout-minutes)
+      TIMEOUT_MINUTES="${2:-}"
+      shift 2
+      ;;
+    --poll-seconds)
+      POLL_SECONDS="${2:-}"
+      shift 2
+      ;;
+    --linux-heavy-runner)
+      LINUX_HEAVY_RUNNER="${2:-}"
+      shift 2
+      ;;
+    --macos-heavy-runner)
+      MACOS_HEAVY_RUNNER="${2:-}"
+      shift 2
+      ;;
+    --sdk-min-free-disk-gb)
+      SDK_MIN_FREE_DISK_GB="${2:-}"
+      shift 2
+      ;;
+    --engine-min-free-disk-gb)
+      ENGINE_MIN_FREE_DISK_GB="${2:-}"
+      shift 2
+      ;;
+    --base-flutter-engine-revision)
+      BASE_FLUTTER_ENGINE_REVISION="${2:-}"
+      shift 2
+      ;;
+    --skip-gclient-sync)
+      RUN_GCLIENT_SYNC=false
+      shift
+      ;;
+    -h|--help)
+      usage
+      exit 0
+      ;;
+    *)
+      echo "unknown argument: $1" >&2
+      usage
+      exit 64
+      ;;
+  esac
+done
+
+if [[ -z "$REPO" ]]; then
+  echo "--repo owner/name is required" >&2
+  usage
+  exit 64
+fi
+
+if [[ -z "$REF" ]]; then
+  REF="$(git -C "$ROOT" branch --show-current 2>/dev/null || true)"
+fi
+if [[ -z "$REF" ]]; then
+  echo "--ref is required when the current checkout is detached" >&2
+  exit 64
+fi
+
+run_fields=(
+  -f full_sdk_build=true
+  -f run_gclient_sync="$RUN_GCLIENT_SYNC"
+  -f run_runtime_smokes=false
+)
+[[ -z "$LINUX_HEAVY_RUNNER" ]] || run_fields+=(-f linux_heavy_runner="$LINUX_HEAVY_RUNNER")
+[[ -z "$MACOS_HEAVY_RUNNER" ]] || run_fields+=(-f macos_heavy_runner="$MACOS_HEAVY_RUNNER")
+[[ -z "$SDK_MIN_FREE_DISK_GB" ]] || run_fields+=(-f sdk_min_free_disk_gb="$SDK_MIN_FREE_DISK_GB")
+[[ -z "$ENGINE_MIN_FREE_DISK_GB" ]] || run_fields+=(-f engine_min_free_disk_gb="$ENGINE_MIN_FREE_DISK_GB")
+[[ -z "$BASE_FLUTTER_ENGINE_REVISION" ]] || run_fields+=(-f base_flutter_engine_revision="$BASE_FLUTTER_ENGINE_REVISION")
+
+api_token() {
+  if [[ -n "${GITHUB_TOKEN:-}" ]]; then
+    printf '%s' "$GITHUB_TOKEN"
+  elif [[ -n "${GH_TOKEN:-}" ]]; then
+    printf '%s' "$GH_TOKEN"
+  else
+    echo "GITHUB_TOKEN or GH_TOKEN is required when gh is not installed" >&2
+    exit 69
+  fi
+}
+
+api_require_tool() {
+  local tool="$1"
+  if ! command -v "$tool" >/dev/null 2>&1; then
+    echo "$tool is required when gh is not installed" >&2
+    exit 69
+  fi
+}
+
+api_request() {
+  local method="$1"
+  local path="$2"
+  local data="${3:-}"
+  local token
+  token="$(api_token)"
+
+  local curl_args=(
+    -fsSL
+    -X "$method"
+    -H "Accept: application/vnd.github+json"
+    -H "Authorization: Bearer $token"
+    -H "X-GitHub-Api-Version: 2022-11-28"
+  )
+  if [[ -n "$data" ]]; then
+    curl_args+=(-H "Content-Type: application/json" -d "$data")
+  fi
+
+  curl "${curl_args[@]}" "$GITHUB_API_URL/repos/$REPO$path"
+}
+
+api_dispatch_payload() {
+  local inputs_filter
+  inputs_filter='{full_sdk_build: "true", run_gclient_sync: $run_gclient_sync, run_runtime_smokes: "false"}'
+  local jq_args=(
+    --arg ref "$REF"
+    --arg run_gclient_sync "$RUN_GCLIENT_SYNC"
+  )
+  if [[ -n "$LINUX_HEAVY_RUNNER" ]]; then
+    inputs_filter="$inputs_filter + {linux_heavy_runner: \$linux_heavy_runner}"
+    jq_args+=(--arg linux_heavy_runner "$LINUX_HEAVY_RUNNER")
+  fi
+  if [[ -n "$MACOS_HEAVY_RUNNER" ]]; then
+    inputs_filter="$inputs_filter + {macos_heavy_runner: \$macos_heavy_runner}"
+    jq_args+=(--arg macos_heavy_runner "$MACOS_HEAVY_RUNNER")
+  fi
+  if [[ -n "$SDK_MIN_FREE_DISK_GB" ]]; then
+    inputs_filter="$inputs_filter + {sdk_min_free_disk_gb: \$sdk_min_free_disk_gb}"
+    jq_args+=(--arg sdk_min_free_disk_gb "$SDK_MIN_FREE_DISK_GB")
+  fi
+  if [[ -n "$ENGINE_MIN_FREE_DISK_GB" ]]; then
+    inputs_filter="$inputs_filter + {engine_min_free_disk_gb: \$engine_min_free_disk_gb}"
+    jq_args+=(--arg engine_min_free_disk_gb "$ENGINE_MIN_FREE_DISK_GB")
+  fi
+  if [[ -n "$BASE_FLUTTER_ENGINE_REVISION" ]]; then
+    inputs_filter="$inputs_filter + {base_flutter_engine_revision: \$base_flutter_engine_revision}"
+    jq_args+=(--arg base_flutter_engine_revision "$BASE_FLUTTER_ENGINE_REVISION")
+  fi
+
+  jq -n "${jq_args[@]}" "{ref: \$ref, inputs: ($inputs_filter)}"
+}
+
+api_download_artifacts() {
+  rm -rf "$DOWNLOAD_DIR"
+  mkdir -p "$DOWNLOAD_DIR"
+
+  local page=1
+  local downloaded_count=0
+  while true; do
+    local response
+    response="$(api_request GET "/actions/runs/$run_id/artifacts?per_page=100&page=$page")"
+    local artifact_count
+    artifact_count="$(jq '.artifacts | length' <<<"$response")"
+    [[ "$artifact_count" == "0" ]] && break
+
+    while IFS= read -r artifact; do
+      local name
+      local url
+      name="$(jq -r '.name' <<<"$artifact")"
+      url="$(jq -r '.archive_download_url' <<<"$artifact")"
+      case "$name" in
+        ""|*/*|*..*)
+          echo "unsafe GitHub artifact name: $name" >&2
+          exit 70
+          ;;
+      esac
+      if [[ -z "$url" || "$url" == "null" ]]; then
+        echo "missing archive_download_url for artifact: $name" >&2
+        exit 70
+      fi
+
+      local artifact_dir
+      local zip_path
+      artifact_dir="$DOWNLOAD_DIR/$name"
+      zip_path="$(mktemp "${TMPDIR:-/tmp}/github-artifact.XXXXXX")"
+      curl \
+        -fsSL \
+        -L \
+        -H "Accept: application/vnd.github+json" \
+        -H "Authorization: Bearer $(api_token)" \
+        -H "X-GitHub-Api-Version: 2022-11-28" \
+        -o "$zip_path" \
+        "$url"
+      rm -rf "$artifact_dir"
+      mkdir -p "$artifact_dir"
+      unzip -q "$zip_path" -d "$artifact_dir"
+      rm -f "$zip_path"
+      downloaded_count=$((downloaded_count + 1))
+    done < <(jq -c '.artifacts[] | select(.expired | not)' <<<"$response")
+
+    page=$((page + 1))
+  done
+
+  if [[ "$downloaded_count" -eq 0 ]]; then
+    echo "no non-expired artifacts were available for workflow run $run_id" >&2
+    exit 70
+  fi
+}
+
+use_gh=0
+if command -v gh >/dev/null 2>&1; then
+  use_gh=1
+else
+  api_require_tool curl
+  api_require_tool jq
+  api_require_tool unzip
+  api_token >/dev/null
+fi
+
+echo "Dispatching $WORKFLOW on $REPO@$REF with full_sdk_build=true"
+start_epoch="$(date +%s)"
+start_iso="$(date -u -r "$start_epoch" +"%Y-%m-%dT%H:%M:%SZ" 2>/dev/null || date -u -d "@$start_epoch" +"%Y-%m-%dT%H:%M:%SZ")"
+if [[ "$use_gh" == "1" ]]; then
+  gh workflow run "$WORKFLOW" \
+    --repo "$REPO" \
+    --ref "$REF" \
+    "${run_fields[@]}"
+else
+  api_request POST "/actions/workflows/$WORKFLOW/dispatches" "$(api_dispatch_payload)" >/dev/null
+fi
+
+run_id=""
+for _ in {1..40}; do
+  if [[ "$use_gh" == "1" ]]; then
+    run_list_args=(
+      --repo "$REPO"
+      --workflow "$WORKFLOW"
+      --event workflow_dispatch
+      --json databaseId,createdAt
+      --limit 20
+    )
+    if [[ "$REF" =~ ^[0-9a-fA-F]{40}$ ]]; then
+      run_list_args+=(--commit "$REF")
+    else
+      run_list_args+=(--branch "$REF")
+    fi
+    run_id="$(
+      gh run list \
+        "${run_list_args[@]}" \
+        --jq ".[] | select(.createdAt >= \"$start_iso\") | .databaseId" \
+        |
+        head -n 1
+    )"
+  else
+    runs_response="$(api_request GET "/actions/workflows/$WORKFLOW/runs?event=workflow_dispatch&per_page=20")"
+    run_id="$(
+      jq -r \
+        --arg ref "$REF" \
+        --arg start_iso "$start_iso" \
+        '
+          .workflow_runs
+          | map(select(.created_at >= $start_iso))
+          | map(select(.head_branch == $ref or .head_sha == $ref))
+          | sort_by(.created_at)
+          | reverse
+          | .[0].id // ""
+        ' \
+        <<<"$runs_response"
+    )"
+  fi
+  [[ -z "$run_id" ]] || break
+  sleep 3
+done
+
+if [[ -z "$run_id" ]]; then
+  echo "unable to find dispatched workflow run for $WORKFLOW on $REF" >&2
+  exit 70
+fi
+
+echo "Waiting for hosted full SDK run: $run_id"
+deadline=$((start_epoch + TIMEOUT_MINUTES * 60))
+run_head_sha=""
+while true; do
+  if [[ "$use_gh" == "1" ]]; then
+    IFS=$'\t' read -r status conclusion url run_head_sha < <(
+      gh run view "$run_id" \
+        --repo "$REPO" \
+        --json status,conclusion,url,headSha \
+        --jq '[.status, (.conclusion // ""), .url, (.headSha // "")] | @tsv'
+    )
+  else
+    run_response="$(api_request GET "/actions/runs/$run_id")"
+    IFS=$'\t' read -r status conclusion url run_head_sha < <(
+      jq -r '[.status, (.conclusion // ""), .html_url, (.head_sha // "")] | @tsv' \
+        <<<"$run_response"
+    )
+  fi
+  echo "run $run_id status=$status conclusion=${conclusion:-null} url=$url"
+
+  if [[ "$status" == "completed" ]]; then
+    if [[ "$conclusion" != "success" ]]; then
+      echo "hosted full SDK build failed: conclusion=$conclusion" >&2
+      exit 70
+    fi
+    break
+  fi
+  if [[ "$(date +%s)" -ge "$deadline" ]]; then
+    echo "timed out waiting for hosted full SDK build after $TIMEOUT_MINUTES minutes" >&2
+    exit 70
+  fi
+  sleep "$POLL_SECONDS"
+done
+
+if [[ "$use_gh" == "1" ]]; then
+  rm -rf "$DOWNLOAD_DIR"
+  mkdir -p "$DOWNLOAD_DIR"
+  gh run download "$run_id" --repo "$REPO" --dir "$DOWNLOAD_DIR"
+else
+  api_download_artifacts
+fi
+if [[ -z "$run_head_sha" ]]; then
+  echo "unable to read headSha for workflow run $run_id" >&2
+  exit 70
+fi
+"$ROOT/scripts/verify_downloaded_release_artifacts.sh" \
+  --github-sha "$run_head_sha" \
+  "$DOWNLOAD_DIR"
+
+echo "hosted full SDK build verified: $run_id"

scripts/verify_ios_interpreter_route.sh

@@ -14,6 +14,7 @@ CHECKED_IPA=""
 CHECKED_PATCH_ARTIFACT=""
 ENTITLEMENTS_CHECKED=0
 APP_STORE_STRICT_CHECKED=0
+NO_BUNDLED_KEY_CHECKED=0
 CLEANUP_DIR=""
 
 cleanup() {
@@ -35,14 +36,14 @@ read_gn_value() {
     $1 == key && $2 == "=" {
       value = $0
       sub("^[[:space:]]*" key "[[:space:]]*=[[:space:]]*", "", value)
-      print value
+      sub("[[:space:]]*$", "", value)
       found = 1
-      exit
     }
     END {
       if (!found) {
         exit 1
       }
+      print value
     }
   ' "$file"
 }
@@ -66,9 +67,11 @@ verify_ios_engine_args() {
 
   require_gn_value "$args_file" target_os '"ios"'
   require_gn_value "$args_file" dart_dynamic_modules false
+  require_gn_value "$args_file" dart_enable_aot_patching true
   require_gn_value "$args_file" dart_enable_shorebird_interpreter true
   require_gn_value "$args_file" shorebird_use_interpreter true
   require_gn_value "$args_file" shorebird_enable_aot_patching false
+  require_gn_value "$args_file" flutter_prebuilt_dart_sdk false
 }
 
 verify_host_engine_args() {
@@ -77,8 +80,10 @@ verify_host_engine_args() {
 
   require_gn_value "$args_file" target_os '"mac"'
   require_gn_value "$args_file" dart_dynamic_modules false
+  require_gn_value "$args_file" dart_enable_aot_patching true
   require_gn_value "$args_file" dart_enable_shorebird_interpreter true
   require_gn_value "$args_file" shorebird_use_interpreter true
+  require_gn_value "$args_file" flutter_prebuilt_dart_sdk false
 }
 
 app_bundle_from_ipa() {
@@ -143,6 +148,24 @@ verify_entitlements() {
   fi
 }
 
+verify_no_bundled_patch_key() {
+  local app_bundle="$1"
+  [[ "$APP_STORE_STRICT" == "1" ]] || return 0
+
+  local shorebird_yaml
+  shorebird_yaml="$(
+    find "$app_bundle" -name "shorebird.yaml" -type f -print -quit
+  )"
+  if [[ -z "$shorebird_yaml" ]]; then
+    return 0
+  fi
+
+  if grep -Eq '^[[:space:]]*aot_patch_key_hex[[:space:]]*:' "$shorebird_yaml"; then
+    fail "APP_STORE_STRICT=1 rejects bundled aot_patch_key_hex in $shorebird_yaml"
+  fi
+  NO_BUNDLED_KEY_CHECKED=1
+}
+
 verify_app_bundle() {
   if [[ -n "$IOS_APP_BUNDLE" && -n "$IOS_IPA" ]]; then
     fail "set only one of IOS_APP_BUNDLE or IOS_IPA"
@@ -165,6 +188,7 @@ verify_app_bundle() {
   fi
 
   verify_entitlements "$IOS_APP_BUNDLE"
+  verify_no_bundled_patch_key "$IOS_APP_BUNDLE"
 }
 
 file_magic_hex() {
@@ -186,31 +210,105 @@ verify_patch_artifact() {
       ;;
   esac
 
-  local compact_json
+  local python_bin
-  compact_json="$(LC_ALL=C tr -d '[:space:]' < "$IOS_PATCH_ARTIFACT")"
+  python_bin=python3
+  if ! command -v "$python_bin" >/dev/null 2>&1; then
+    python_bin=python
+  fi
+  command -v "$python_bin" >/dev/null 2>&1 ||
+    fail "python3 or python is required to inspect IOS_PATCH_ARTIFACT"
 
-  if [[ "$compact_json" != \{* ]]; then
+  "$python_bin" - "$IOS_PATCH_ARTIFACT" <<'PY'
-    fail "iOS patch artifact must be the encrypted open JSON wrapper, not a raw native/code payload"
+import base64
-  fi
+import binascii
-  if ! grep -Fq '"format":"open-aot-vmcode-encrypted-v1"' <<<"$compact_json"; then
+import json
-    fail "iOS patch artifact is not an open encrypted VM code artifact"
+import re
-  fi
+import sys
-  if grep -Fq '"runtime_mode":"dart-dynamic-modules"' <<<"$compact_json" ||
+
-     grep -Fq '"runtime_mode":"dynamic-modules"' <<<"$compact_json"; then
+path = sys.argv[1]
-    fail "iOS patch artifact uses DART_DYNAMIC_MODULES runtime mode"
+
-  fi
+try:
-  if ! grep -Fq '"runtime_mode":"dart-bytecode-interpreter"' <<<"$compact_json"; then
+    with open(path, encoding="utf-8") as file:
-    fail "iOS patch artifact must declare runtime_mode dart-bytecode-interpreter"
+        artifact = json.load(file)
-  fi
+except (OSError, UnicodeDecodeError, json.JSONDecodeError) as error:
-  if ! grep -Fq '"target_os":"ios"' <<<"$compact_json"; then
+    raise SystemExit(
-    fail "iOS patch artifact must target iOS"
+        "iOS patch artifact must be the encrypted open JSON wrapper, "
-  fi
+        f"not a raw native/code payload: {error}"
-  if ! grep -Fq '"target_arch":"arm64"' <<<"$compact_json"; then
+    )
-    fail "iOS patch artifact must target arm64"
+
-  fi
+if not isinstance(artifact, dict):
-  if ! grep -Fq '"payload_kind":"full-snapshot"' <<<"$compact_json"; then
+    raise SystemExit("iOS patch artifact JSON must be an object")
-    fail "current iOS interpreter mapper requires payload_kind full-snapshot"
+
-  fi
+metadata = artifact.get("metadata")
+if not isinstance(metadata, dict):
+    raise SystemExit("iOS patch artifact must contain metadata object")
+
+
+def require(mapping, key, expected, scope):
+    actual = mapping.get(key)
+    if actual != expected:
+        raise SystemExit(
+            f"iOS patch artifact {scope}.{key} is {actual!r}; "
+            f"expected {expected!r}"
+        )
+
+
+require(artifact, "format", "open-aot-vmcode-encrypted-v1", "artifact")
+runtime_mode = metadata.get("runtime_mode")
+if runtime_mode in {"dart-dynamic-modules", "dynamic-modules"}:
+    raise SystemExit("iOS patch artifact uses DART_DYNAMIC_MODULES runtime mode")
+require(metadata, "runtime_mode", "dart-bytecode-interpreter", "metadata")
+require(metadata, "target_os", "ios", "metadata")
+require(metadata, "target_arch", "arm64", "metadata")
+require(artifact, "payload_kind", "full-snapshot", "artifact")
+
+encryption = artifact.get("encryption")
+if not isinstance(encryption, dict):
+    raise SystemExit("iOS patch artifact must contain encryption object")
+require(encryption, "algorithm", "AES-256-GCM", "encryption")
+
+
+def require_base64(mapping, key, scope):
+    value = mapping.get(key)
+    if not isinstance(value, str) or not value:
+        raise SystemExit(f"iOS patch artifact {scope}.{key} must be non-empty")
+    try:
+        decoded = base64.b64decode(value, validate=True)
+    except (binascii.Error, ValueError) as error:
+        raise SystemExit(
+            f"iOS patch artifact {scope}.{key} is not valid base64: {error}"
+        )
+    if not decoded:
+        raise SystemExit(f"iOS patch artifact {scope}.{key} decodes to empty bytes")
+    return decoded
+
+
+require_base64(artifact, "encrypted_payload_base64", "artifact")
+require_base64(encryption, "nonce_base64", "encryption")
+require_base64(encryption, "tag_base64", "encryption")
+
+key_id = encryption.get("key_id")
+if not isinstance(key_id, str) or not key_id:
+    raise SystemExit("iOS patch artifact encryption.key_id must be non-empty")
+
+hex_pattern = re.compile(r"^[0-9a-f]{64}$")
+for scope, mapping, key in (
+    ("artifact", artifact, "payload_sha256"),
+    ("encryption", encryption, "aad_sha256"),
+):
+    value = mapping.get(key)
+    if not isinstance(value, str) or not hex_pattern.fullmatch(value):
+        raise SystemExit(
+            f"iOS patch artifact {scope}.{key} must be a lowercase SHA-256 hex digest"
+        )
+
+reconstructed_size = artifact.get("reconstructed_size")
+if reconstructed_size is not None:
+    if not isinstance(reconstructed_size, int) or reconstructed_size <= 0:
+        raise SystemExit(
+            "iOS patch artifact reconstructed_size must be a positive integer"
+        )
+PY
 
   CHECKED_PATCH_ARTIFACT="$IOS_PATCH_ARTIFACT"
 }
@@ -240,6 +338,9 @@ fi
 if [[ "$APP_STORE_STRICT_CHECKED" == "1" ]]; then
   echo "  App Store strict: get-task-allow is not true"
 fi
+if [[ "$NO_BUNDLED_KEY_CHECKED" == "1" ]]; then
+  echo "  key material:     no bundled aot_patch_key_hex"
+fi
 if [[ -n "$CHECKED_PATCH_ARTIFACT" ]]; then
   echo "  patch artifact:   encrypted interpreter full-snapshot for ios/arm64"
 fi

scripts/verify_ios_interpreter_route_validator.sh

@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/ios-route-validator.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+IOS_ENGINE_DIR="$TMP_DIR/ios_release"
+HOST_ENGINE_DIR="$TMP_DIR/host_release_arm64"
+mkdir -p "$IOS_ENGINE_DIR" "$HOST_ENGINE_DIR"
+
+cat > "$IOS_ENGINE_DIR/args.gn" <<'EOF'
+target_os = "android"
+target_os = "ios"
+dart_dynamic_modules = false
+dart_enable_aot_patching = false
+dart_enable_aot_patching = true
+dart_enable_shorebird_interpreter = false
+dart_enable_shorebird_interpreter = true
+shorebird_use_interpreter = false
+shorebird_use_interpreter = true
+shorebird_enable_aot_patching = true
+shorebird_enable_aot_patching = false
+flutter_prebuilt_dart_sdk = false
+EOF
+
+cat > "$HOST_ENGINE_DIR/args.gn" <<'EOF'
+target_os = "linux"
+target_os = "mac"
+dart_dynamic_modules = false
+dart_enable_aot_patching = false
+dart_enable_aot_patching = true
+dart_enable_shorebird_interpreter = false
+dart_enable_shorebird_interpreter = true
+shorebird_use_interpreter = false
+shorebird_use_interpreter = true
+flutter_prebuilt_dart_sdk = false
+EOF
+
+write_artifact() {
+  local path="$1"
+  local runtime_mode="$2"
+  local target_os="${3:-ios}"
+  cat > "$path" <<EOF
+{
+  "format": "open-aot-vmcode-encrypted-v1",
+  "metadata": {
+    "app_id": "app.test",
+    "app_build_id": "1",
+    "flavor_id": "pro",
+    "license_type": "pro",
+    "sdk_hash": "sdk",
+    "base_snapshot_hash": "0000000000000000000000000000000000000000000000000000000000000000",
+    "patch_snapshot_hash": "1111111111111111111111111111111111111111111111111111111111111111",
+    "target_os": "$target_os",
+    "target_arch": "arm64",
+    "runtime_mode": "$runtime_mode"
+  },
+  "payload_kind": "full-snapshot",
+  "reconstructed_size": 4,
+  "payload_sha256": "2222222222222222222222222222222222222222222222222222222222222222",
+  "encrypted_payload_base64": "AQIDBA==",
+  "encryption": {
+    "algorithm": "AES-256-GCM",
+    "key_id": "test-key",
+    "nonce_base64": "AQIDBAUGBwgJCgsM",
+    "tag_base64": "AQIDBAUGBwgJCgsMDQ4PEA==",
+    "aad_sha256": "3333333333333333333333333333333333333333333333333333333333333333"
+  }
+}
+EOF
+}
+
+valid_artifact="$TMP_DIR/valid.vmcode"
+write_artifact "$valid_artifact" "dart-bytecode-interpreter"
+IOS_ENGINE_DIR="$IOS_ENGINE_DIR" \
+  HOST_ENGINE_DIR="$HOST_ENGINE_DIR" \
+  IOS_PATCH_ARTIFACT="$valid_artifact" \
+  "$ROOT/scripts/verify_ios_interpreter_route.sh" >/dev/null
+
+bad_runtime="$TMP_DIR/bad-runtime.vmcode"
+write_artifact "$bad_runtime" "dart-dynamic-modules"
+if IOS_ENGINE_DIR="$IOS_ENGINE_DIR" \
+    HOST_ENGINE_DIR="$HOST_ENGINE_DIR" \
+    IOS_PATCH_ARTIFACT="$bad_runtime" \
+    "$ROOT/scripts/verify_ios_interpreter_route.sh" >/dev/null 2>&1; then
+  echo "iOS route validator unexpectedly accepted DART_DYNAMIC_MODULES metadata" >&2
+  exit 70
+fi
+
+bad_target="$TMP_DIR/bad-target.vmcode"
+write_artifact "$bad_target" "dart-bytecode-interpreter" "android"
+if IOS_ENGINE_DIR="$IOS_ENGINE_DIR" \
+    HOST_ENGINE_DIR="$HOST_ENGINE_DIR" \
+    IOS_PATCH_ARTIFACT="$bad_target" \
+    "$ROOT/scripts/verify_ios_interpreter_route.sh" >/dev/null 2>&1; then
+  echo "iOS route validator unexpectedly accepted a non-iOS patch artifact" >&2
+  exit 70
+fi
+
+bad_json="$TMP_DIR/bad-json.vmcode"
+printf '{"format":"open-aot-vmcode-encrypted-v1"\n' > "$bad_json"
+if IOS_ENGINE_DIR="$IOS_ENGINE_DIR" \
+    HOST_ENGINE_DIR="$HOST_ENGINE_DIR" \
+    IOS_PATCH_ARTIFACT="$bad_json" \
+    "$ROOT/scripts/verify_ios_interpreter_route.sh" >/dev/null 2>&1; then
+  echo "iOS route validator unexpectedly accepted malformed JSON" >&2
+  exit 70
+fi
+
+bad_native="$TMP_DIR/bad-native.vmcode"
+printf '\xcf\xfa\xed\xfe' > "$bad_native"
+if IOS_ENGINE_DIR="$IOS_ENGINE_DIR" \
+    HOST_ENGINE_DIR="$HOST_ENGINE_DIR" \
+    IOS_PATCH_ARTIFACT="$bad_native" \
+    "$ROOT/scripts/verify_ios_interpreter_route.sh" >/dev/null 2>&1; then
+  echo "iOS route validator unexpectedly accepted a Mach-O patch artifact" >&2
+  exit 70
+fi
+
+echo "iOS interpreter route validator smoke test passed"

scripts/verify_open_infrastructure_defaults.sh

@@ -0,0 +1,121 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+fail() {
+  echo "error: $*" >&2
+  exit 70
+}
+
+require_contains() {
+  local path="$1"
+  local needle="$2"
+  grep -Fq "$needle" "$path" || fail "$path is missing required text: $needle"
+}
+
+reject_contains() {
+  local path="$1"
+  local needle="$2"
+  if grep -Fq "$needle" "$path"; then
+    fail "$path contains forbidden text: $needle"
+  fi
+}
+
+check_forbidden_in_file() {
+  local path="$1"
+  local pattern
+
+  [[ -f "$path" ]] || fail "missing open-infrastructure check input: $path"
+  for pattern in "${FORBIDDEN_PATTERNS[@]}"; do
+    reject_contains "$path" "$pattern"
+  done
+}
+
+check_forbidden_in_tree() {
+  local tree="$1"
+  local extension="$2"
+  local path
+
+  [[ -d "$tree" ]] || fail "missing open-infrastructure check tree: $tree"
+  while IFS= read -r -d '' path; do
+    check_forbidden_in_file "$path"
+  done < <(find "$tree" -type f -name "*.$extension" -print0)
+}
+
+FORBIDDEN_PATTERNS=(
+  "https://download.shorebird.dev"
+  "download.shorebird.dev"
+  "api.shorebird.dev"
+  "auth.shorebird.dev"
+  "console.shorebird.dev"
+  "cdn.shorebird.cloud"
+  "git@github.com:shorebirdtech/dart-sdk.git"
+  "github.com/shorebirdtech/updater.git"
+  "github.com/shorebirdtech/flutter.git"
+  "shorebird-dart-sdk-prebuilt"
+  "shorebirdtech/_build_engine"
+)
+
+BUILD_SENSITIVE_FILES=(
+  "$ROOT/.gitmodules"
+  "$ROOT/flutter/DEPS"
+  "$ROOT/flutter/bin/internal/update_dart_sdk.ps1"
+  "$ROOT/flutter/bin/internal/update_dart_sdk.sh"
+  "$ROOT/flutter/dev/bots/post_process_docs.dart"
+  "$ROOT/flutter/dev/bots/unpublish_package.dart"
+  "$ROOT/flutter/dev/integration_tests/pure_android_host_apps/android_host_app_v2_embedding/settings.gradle"
+  "$ROOT/flutter/dev/integration_tests/pure_android_host_apps/host_app_kotlin_gradle_dsl/settings.gradle.kts"
+  "$ROOT/flutter/dev/tools/create_api_docs.dart"
+  "$ROOT/flutter/engine/src/flutter/build/zip_bundle.gni"
+  "$ROOT/flutter/engine/src/flutter/lib/web_ui/dev/steps/copy_artifacts_step.dart"
+  "$ROOT/flutter/packages/flutter_tools/gradle/aar_init_script.gradle"
+  "$ROOT/flutter/packages/flutter_tools/gradle/src/main/kotlin/FlutterPluginConstants.kt"
+  "$ROOT/flutter/packages/flutter_tools/lib/src/cache.dart"
+  "$ROOT/flutter/packages/flutter_tools/lib/src/http_host_validator.dart"
+  "$ROOT/flutter/packages/flutter_tools/pubspec.yaml"
+  "$ROOT/flutter/packages/shorebird_tests/test/shorebird_tests.dart"
+  "$ROOT/scripts/write_gclient.sh"
+  "$ROOT/shorebird/bin/shorebird.ps1"
+  "$ROOT/shorebird/third_party/flutter/bin/internal/shared.sh"
+  "$ROOT/updater/library/src/config.rs"
+)
+
+for path in "${BUILD_SENSITIVE_FILES[@]}"; do
+  check_forbidden_in_file "$path"
+done
+
+check_forbidden_in_tree "$ROOT/shorebird/packages/artifact_proxy/lib" dart
+check_forbidden_in_tree "$ROOT/shorebird/packages/shorebird_cli/lib" dart
+check_forbidden_in_tree "$ROOT/shorebird/packages/shorebird_code_push_client/lib" dart
+
+require_contains "$ROOT/.gitmodules" "https://github.com/tony-cloud/dart-sdk.git"
+require_contains "$ROOT/.gitmodules" "https://github.com/tony-cloud/flutter.git"
+require_contains "$ROOT/.gitmodules" "https://git.tonycloud.org/flutter/shorebird.git"
+require_contains "$ROOT/.gitmodules" "https://git.tonycloud.org/flutter/shorebird-server.git"
+require_contains "$ROOT/.gitmodules" "https://git.tonycloud.org/flutter/shorebird-updater.git"
+
+require_contains "$ROOT/flutter/DEPS" '"dart_sdk_git": "https://github.com/tony-cloud/dart-sdk.git"'
+require_contains "$ROOT/flutter/DEPS" '"updater_git": "https://git.tonycloud.org/flutter/shorebird-updater.git"'
+
+require_contains "$ROOT/flutter/packages/flutter_tools/lib/src/cache.dart" \
+  "kOpenFlutterStorageUrl = 'http://localhost:8080/download.flutter.io'"
+require_contains "$ROOT/flutter/bin/internal/update_dart_sdk.sh" \
+  "http://localhost:8080/download.flutter.io"
+require_contains "$ROOT/flutter/bin/internal/update_dart_sdk.ps1" \
+  "http://localhost:8080/download.flutter.io"
+require_contains "$ROOT/flutter/packages/flutter_tools/gradle/src/main/kotlin/FlutterPluginConstants.kt" \
+  'DEFAULT_MAVEN_HOST = "http://localhost:8080/download.flutter.io"'
+require_contains "$ROOT/flutter/dev/tools/create_api_docs.dart" \
+  "Platform.environment['FLUTTER_STORAGE_BASE_URL']"
+require_contains "$ROOT/flutter/packages/shorebird_tests/test/shorebird_tests.dart" \
+  "'FLUTTER_STORAGE_BASE_URL': 'http://localhost:8080/download.flutter.io'"
+
+require_contains "$ROOT/shorebird/packages/shorebird_cli/lib/src/shorebird_env.dart" \
+  "defaultHostedUrl = 'http://localhost:8080'"
+require_contains "$ROOT/shorebird/packages/shorebird_cli/lib/src/cache.dart" \
+  "defaultArtifactBaseUrl = 'http://localhost:8080/artifacts'"
+require_contains "$ROOT/updater/library/src/config.rs" \
+  'const DEFAULT_BASE_URL: &str = "http://localhost:8080";'
+
+echo "open infrastructure defaults check passed"

scripts/verify_powershell_open_defaults.sh

@@ -0,0 +1,87 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+fail() {
+  echo "error: $*" >&2
+  exit 70
+}
+
+require_contains() {
+  local path="$1"
+  local needle="$2"
+  grep -Fq "$needle" "$path" || fail "$path is missing required text: $needle"
+}
+
+reject_contains() {
+  local path="$1"
+  local needle="$2"
+  if grep -Fq "$needle" "$path"; then
+    fail "$path contains forbidden text: $needle"
+  fi
+}
+
+shorebird_launcher="$ROOT/shorebird/bin/shorebird.ps1"
+flutter_dart_updater="$ROOT/flutter/bin/internal/update_dart_sdk.ps1"
+
+[[ -f "$shorebird_launcher" ]] || fail "missing PowerShell launcher: $shorebird_launcher"
+[[ -f "$flutter_dart_updater" ]] || fail "missing Flutter Dart SDK updater: $flutter_dart_updater"
+
+require_contains "$shorebird_launcher" \
+  '$defaultFlutterGitUrl = "https://github.com/tony-cloud/flutter.git"'
+require_contains "$shorebird_launcher" \
+  '$defaultFlutterStorageBaseUrl = "http://localhost:8080/download.flutter.io"'
+require_contains "$shorebird_launcher" 'SHOREBIRD_FLUTTER_GIT_URL'
+require_contains "$shorebird_launcher" 'SHOREBIRD_FLUTTER_STORAGE_BASE_URL'
+require_contains "$shorebird_launcher" 'FLUTTER_STORAGE_BASE_URL'
+
+require_contains "$flutter_dart_updater" '$Env:FLUTTER_STORAGE_BASE_URL'
+require_contains "$flutter_dart_updater" \
+  '$dartSdkBaseUrl = "http://localhost:8080/download.flutter.io"'
+
+for path in "$shorebird_launcher" "$flutter_dart_updater"; do
+  reject_contains "$path" 'download.shorebird.dev'
+  reject_contains "$path" 'api.shorebird.dev'
+  reject_contains "$path" 'auth.shorebird.dev'
+  reject_contains "$path" 'console.shorebird.dev'
+  reject_contains "$path" 'docs.shorebird.dev'
+  reject_contains "$path" 'github.com/shorebirdtech/flutter.git'
+  reject_contains "$path" 'github.com/shorebirdtech/shorebird'
+  reject_contains "$path" 'git@github.com:shorebirdtech'
+done
+
+if command -v pwsh >/dev/null 2>&1; then
+  SHOREBIRD_POWERSHELL_LAUNCHER="$shorebird_launcher" \
+  FLUTTER_DART_SDK_POWERSHELL_UPDATER="$flutter_dart_updater" \
+  pwsh -NoProfile -NonInteractive -Command '
+    $paths = @(
+      $env:SHOREBIRD_POWERSHELL_LAUNCHER,
+      $env:FLUTTER_DART_SDK_POWERSHELL_UPDATER
+    )
+    $failed = $false
+    foreach ($path in $paths) {
+      $tokens = $null
+      $errors = $null
+      [System.Management.Automation.Language.Parser]::ParseFile(
+        $path,
+        [ref]$tokens,
+        [ref]$errors
+      ) | Out-Null
+      if ($errors.Count -gt 0) {
+        Write-Error "$path has PowerShell parse errors:"
+        foreach ($errorRecord in $errors) {
+          Write-Error "  $($errorRecord.Message)"
+        }
+        $failed = $true
+      }
+    }
+    if ($failed) {
+      exit 70
+    }
+  '
+else
+  echo "warning: pwsh not found; skipped PowerShell parse check" >&2
+fi
+
+echo "PowerShell open-default checks passed"

scripts/verify_release_manifest.sh

@@ -0,0 +1,238 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-release-manifest.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+INPUT_DIR="$TMP_DIR/artifacts"
+mkdir -p "$INPUT_DIR/cli-linux" "$INPUT_DIR/server-linux" "$INPUT_DIR/mirror-patch/artifacts/mirror"
+printf 'cli archive\n' > "$INPUT_DIR/cli-linux/open-shorebird-cli-linux-x64.tar.gz"
+printf 'server archive\n' > "$INPUT_DIR/server-linux/shorebird-server-linux-amd64.tar.gz"
+printf 'patch archive\n' > "$INPUT_DIR/mirror-patch/artifacts/mirror/patch-linux-x64.zip"
+
+"$ROOT/scripts/write_sha256.sh" "$INPUT_DIR/cli-linux/open-shorebird-cli-linux-x64.tar.gz"
+"$ROOT/scripts/write_sha256.sh" "$INPUT_DIR/server-linux/shorebird-server-linux-amd64.tar.gz"
+"$ROOT/scripts/write_sha256.sh" "$INPUT_DIR/mirror-patch/artifacts/mirror/patch-linux-x64.zip"
+
+"$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+  "$INPUT_DIR" \
+  --github-sha test-sha \
+  --require 'cli-linux/*open-shorebird-cli-linux-x64.tar.gz' \
+  --require 'server-linux/*shorebird-server-linux-amd64.tar.gz' \
+  --require 'mirror-patch/*patch-linux-x64.zip' \
+  --output "$TMP_DIR/release-manifest.json"
+
+"$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+  --github-sha test-sha \
+  "$INPUT_DIR" \
+  "$TMP_DIR/release-manifest.json"
+
+"$PYTHON_BIN" - "$TMP_DIR/release-manifest.json" <<'PY'
+import json
+import sys
+
+manifest = json.load(open(sys.argv[1], encoding="utf-8"))
+assert manifest["format_version"] == 1
+assert manifest["github_sha"] == "test-sha"
+assert manifest["artifact_count"] == 3
+paths = {artifact["path"] for artifact in manifest["artifacts"]}
+assert "cli-linux/open-shorebird-cli-linux-x64.tar.gz" in paths
+assert "server-linux/shorebird-server-linux-amd64.tar.gz" in paths
+assert "mirror-patch/artifacts/mirror/patch-linux-x64.zip" in paths
+for artifact in manifest["artifacts"]:
+    assert artifact["artifact_group"] in {
+        "cli-linux",
+        "server-linux",
+        "mirror-patch",
+    }
+    assert artifact["filename"] == artifact["path"].split("/")[-1]
+    assert len(artifact["sha256"]) == 64
+    assert artifact["size"] > 0
+    assert artifact["sidecar"].endswith(".sha256")
+PY
+
+TAMPERED_MANIFEST="$TMP_DIR/tampered-release-manifest.json"
+"$PYTHON_BIN" - "$TMP_DIR/release-manifest.json" "$TAMPERED_MANIFEST" <<'PY'
+import json
+import sys
+
+source, output = sys.argv[1:]
+manifest = json.load(open(source, encoding="utf-8"))
+manifest["artifacts"][0]["sha256"] = "0" * 64
+json.dump(manifest, open(output, "w", encoding="utf-8"))
+PY
+if "$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+    "$INPUT_DIR" \
+    "$TAMPERED_MANIFEST" >/dev/null 2>&1; then
+  echo "validate_release_manifest.py unexpectedly accepted a tampered digest" >&2
+  exit 70
+fi
+
+if "$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+    --github-sha wrong-sha \
+    "$INPUT_DIR" \
+    "$TMP_DIR/release-manifest.json" >"$TMP_DIR/wrong-sha.log" 2>&1; then
+  echo "validate_release_manifest.py unexpectedly accepted the wrong github_sha" >&2
+  exit 70
+fi
+grep -q "github_sha is" "$TMP_DIR/wrong-sha.log"
+
+UNLISTED_ARTIFACTS="$TMP_DIR/unlisted-artifacts"
+cp -R "$INPUT_DIR" "$UNLISTED_ARTIFACTS"
+printf 'extra artifact\n' > "$UNLISTED_ARTIFACTS/extra.tar.gz"
+"$ROOT/scripts/write_sha256.sh" "$UNLISTED_ARTIFACTS/extra.tar.gz"
+if "$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+    "$UNLISTED_ARTIFACTS" \
+    "$TMP_DIR/release-manifest.json" >/dev/null 2>&1; then
+  echo "validate_release_manifest.py unexpectedly accepted an unlisted artifact" >&2
+  exit 70
+fi
+
+UNSAFE_MANIFEST="$TMP_DIR/unsafe-release-manifest.json"
+"$PYTHON_BIN" - "$TMP_DIR/release-manifest.json" "$UNSAFE_MANIFEST" <<'PY'
+import json
+import sys
+
+source, output = sys.argv[1:]
+manifest = json.load(open(source, encoding="utf-8"))
+manifest["artifacts"][0]["path"] = r"cli-linux\open-shorebird-cli-linux-x64.tar.gz"
+manifest["artifacts"][0]["sidecar"] = (
+    r"cli-linux\open-shorebird-cli-linux-x64.tar.gz.sha256"
+)
+json.dump(manifest, open(output, "w", encoding="utf-8"))
+PY
+if "$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+    "$INPUT_DIR" \
+    "$UNSAFE_MANIFEST" >/dev/null 2>&1; then
+  echo "validate_release_manifest.py unexpectedly accepted an unsafe artifact path" >&2
+  exit 70
+fi
+
+BAD_PROVENANCE_MANIFEST="$TMP_DIR/bad-provenance-release-manifest.json"
+"$PYTHON_BIN" - "$TMP_DIR/release-manifest.json" "$BAD_PROVENANCE_MANIFEST" <<'PY'
+import json
+import sys
+
+source, output = sys.argv[1:]
+manifest = json.load(open(source, encoding="utf-8"))
+manifest["artifacts"][0]["artifact_group"] = "wrong-group"
+manifest["artifacts"][1]["filename"] = "wrong-name.tar.gz"
+json.dump(manifest, open(output, "w", encoding="utf-8"))
+PY
+if "$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+    "$INPUT_DIR" \
+    "$BAD_PROVENANCE_MANIFEST" >/dev/null 2>&1; then
+  echo "validate_release_manifest.py unexpectedly accepted bad provenance fields" >&2
+  exit 70
+fi
+
+SYMLINK_LISTED_ARTIFACT="$TMP_DIR/symlink-listed-artifact"
+cp -R "$INPUT_DIR" "$SYMLINK_LISTED_ARTIFACT"
+rm "$SYMLINK_LISTED_ARTIFACT/cli-linux/open-shorebird-cli-linux-x64.tar.gz"
+ln -s "$INPUT_DIR/cli-linux/open-shorebird-cli-linux-x64.tar.gz" \
+  "$SYMLINK_LISTED_ARTIFACT/cli-linux/open-shorebird-cli-linux-x64.tar.gz"
+if "$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+    "$SYMLINK_LISTED_ARTIFACT" \
+    "$TMP_DIR/release-manifest.json" >/dev/null 2>&1; then
+  echo "validate_release_manifest.py unexpectedly accepted a symlink artifact" >&2
+  exit 70
+fi
+
+EMPTY_LISTED_ARTIFACT="$TMP_DIR/empty-listed-artifact"
+cp -R "$INPUT_DIR" "$EMPTY_LISTED_ARTIFACT"
+printf '' > "$EMPTY_LISTED_ARTIFACT/cli-linux/open-shorebird-cli-linux-x64.tar.gz"
+"$ROOT/scripts/write_sha256.sh" \
+  "$EMPTY_LISTED_ARTIFACT/cli-linux/open-shorebird-cli-linux-x64.tar.gz"
+EMPTY_LISTED_MANIFEST="$TMP_DIR/empty-listed-release-manifest.json"
+"$PYTHON_BIN" - "$TMP_DIR/release-manifest.json" "$EMPTY_LISTED_MANIFEST" <<'PY'
+import hashlib
+import json
+import sys
+
+source, output = sys.argv[1:]
+manifest = json.load(open(source, encoding="utf-8"))
+empty_digest = hashlib.sha256(b"").hexdigest()
+for artifact in manifest["artifacts"]:
+    if artifact["path"] == "cli-linux/open-shorebird-cli-linux-x64.tar.gz":
+        artifact["sha256"] = empty_digest
+        artifact["size"] = 0
+json.dump(manifest, open(output, "w", encoding="utf-8"))
+PY
+if "$PYTHON_BIN" "$ROOT/scripts/validate_release_manifest.py" \
+    "$EMPTY_LISTED_ARTIFACT" \
+    "$EMPTY_LISTED_MANIFEST" >"$TMP_DIR/empty-listed.log" 2>&1; then
+  echo "validate_release_manifest.py unexpectedly accepted an empty artifact" >&2
+  exit 70
+fi
+grep -q "empty artifacts are not allowed" "$TMP_DIR/empty-listed.log"
+
+SYMLINK_INPUT="$TMP_DIR/symlink-input"
+mkdir -p "$SYMLINK_INPUT"
+printf 'symlink target\n' > "$SYMLINK_INPUT/target.tar.gz"
+"$ROOT/scripts/write_sha256.sh" "$SYMLINK_INPUT/target.tar.gz"
+ln -s target.tar.gz "$SYMLINK_INPUT/link.tar.gz"
+if "$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+    "$SYMLINK_INPUT" \
+    --output "$TMP_DIR/symlink-input.json" >/dev/null 2>&1; then
+  echo "write_release_manifest.py unexpectedly accepted a symlink artifact" >&2
+  exit 70
+fi
+
+MISSING_SIDECAR="$TMP_DIR/missing-sidecar"
+mkdir -p "$MISSING_SIDECAR"
+printf 'missing sidecar\n' > "$MISSING_SIDECAR/artifact.tar.gz"
+if "$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+    "$MISSING_SIDECAR" \
+    --output "$TMP_DIR/missing.json" >/dev/null 2>&1; then
+  echo "write_release_manifest.py unexpectedly accepted a missing sidecar" >&2
+  exit 70
+fi
+
+BAD_SIDECAR="$TMP_DIR/bad-sidecar"
+mkdir -p "$BAD_SIDECAR"
+printf 'bad sidecar\n' > "$BAD_SIDECAR/artifact.tar.gz"
+printf '%064d  artifact.tar.gz\n' 0 > "$BAD_SIDECAR/artifact.tar.gz.sha256"
+if "$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+    "$BAD_SIDECAR" \
+    --output "$TMP_DIR/bad.json" >/dev/null 2>&1; then
+  echo "write_release_manifest.py unexpectedly accepted a bad sidecar" >&2
+  exit 70
+fi
+
+EMPTY_ARTIFACT="$TMP_DIR/empty-artifact"
+mkdir -p "$EMPTY_ARTIFACT"
+printf '' > "$EMPTY_ARTIFACT/artifact.tar.gz"
+"$ROOT/scripts/write_sha256.sh" "$EMPTY_ARTIFACT/artifact.tar.gz"
+if "$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+    "$EMPTY_ARTIFACT" \
+    --output "$TMP_DIR/empty.json" >"$TMP_DIR/empty-artifact.log" 2>&1; then
+  echo "write_release_manifest.py unexpectedly accepted an empty artifact" >&2
+  exit 70
+fi
+grep -q "empty artifacts are not allowed" "$TMP_DIR/empty-artifact.log"
+
+ORPHAN_SIDECAR="$TMP_DIR/orphan-sidecar"
+mkdir -p "$ORPHAN_SIDECAR"
+printf '%064d  missing.tar.gz\n' 0 > "$ORPHAN_SIDECAR/missing.tar.gz.sha256"
+if "$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+    "$ORPHAN_SIDECAR" \
+    --output "$TMP_DIR/orphan.json" >/dev/null 2>&1; then
+  echo "write_release_manifest.py unexpectedly accepted an orphan sidecar" >&2
+  exit 70
+fi
+
+if "$PYTHON_BIN" "$ROOT/scripts/write_release_manifest.py" \
+    "$INPUT_DIR" \
+    --require 'missing-artifact/*.tar.gz' \
+    --output "$TMP_DIR/missing-required.json" >/dev/null 2>&1; then
+  echo "write_release_manifest.py unexpectedly accepted a missing required artifact" >&2
+  exit 70
+fi
+
+echo "write_release_manifest.py smoke test passed"

scripts/verify_sync_open_sources.sh

@@ -0,0 +1,125 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-source-sync.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+
+init_git_checkout() {
+  local path="$1"
+  mkdir -p "$path"
+  git -C "$path" init -q
+}
+
+real_path() {
+  python3 -c 'import os,sys; print(os.path.realpath(sys.argv[1]))' "$1"
+}
+
+make_workspace() {
+  local workspace="$1"
+
+  mkdir -p "$workspace/scripts"
+  cp "$ROOT/scripts/sync_open_sources.sh" "$workspace/scripts/sync_open_sources.sh"
+  chmod +x "$workspace/scripts/sync_open_sources.sh"
+
+  init_git_checkout "$workspace/dart-sdk"
+  mkdir -p "$workspace/dart-sdk/runtime/vm"
+  : > "$workspace/dart-sdk/runtime/vm/dart_api_impl.h"
+
+  init_git_checkout "$workspace/updater"
+  mkdir -p "$workspace/updater/library/include"
+  : > "$workspace/updater/library/include/updater_engine.h"
+
+  mkdir -p "$workspace/flutter/engine/src/flutter/third_party"
+}
+
+run_sync() {
+  local workspace="$1"
+  DART_SRC="$workspace/dart-sdk" \
+    UPDATER_SRC="$workspace/updater" \
+    "$workspace/scripts/sync_open_sources.sh"
+}
+
+assert_links_to_workspace_sources() {
+  local workspace="$1"
+  local dart_target="$workspace/flutter/engine/src/flutter/third_party/dart"
+  local updater_target="$workspace/flutter/engine/src/flutter/third_party/updater"
+
+  test -L "$dart_target"
+  test -L "$updater_target"
+  [[ "$(real_path "$dart_target")" == "$(real_path "$workspace/dart-sdk")" ]]
+  [[ "$(real_path "$updater_target")" == "$(real_path "$workspace/updater")" ]]
+  test -f "$dart_target/runtime/vm/dart_api_impl.h"
+  test -f "$updater_target/library/include/updater_engine.h"
+}
+
+clean_checkout_workspace="$TMP_DIR/clean-checkouts"
+make_workspace "$clean_checkout_workspace"
+init_git_checkout "$clean_checkout_workspace/flutter/engine/src/flutter/third_party/dart"
+init_git_checkout "$clean_checkout_workspace/flutter/engine/src/flutter/third_party/updater"
+run_sync "$clean_checkout_workspace"
+assert_links_to_workspace_sources "$clean_checkout_workspace"
+run_sync "$clean_checkout_workspace"
+assert_links_to_workspace_sources "$clean_checkout_workspace"
+
+stale_link_workspace="$TMP_DIR/stale-link"
+make_workspace "$stale_link_workspace"
+mkdir -p "$stale_link_workspace/other-dart"
+ln -s "../../../../../other-dart" \
+  "$stale_link_workspace/flutter/engine/src/flutter/third_party/dart"
+if run_sync "$stale_link_workspace" >"$TMP_DIR/stale-link.log" 2>&1; then
+  echo "expected stale Dart symlink to fail" >&2
+  exit 1
+fi
+grep -q "Dart SDK target symlink points at" "$TMP_DIR/stale-link.log"
+
+dirty_checkout_workspace="$TMP_DIR/dirty-checkout"
+make_workspace "$dirty_checkout_workspace"
+dirty_dart="$dirty_checkout_workspace/flutter/engine/src/flutter/third_party/dart"
+init_git_checkout "$dirty_dart"
+: > "$dirty_dart/untracked.txt"
+if run_sync "$dirty_checkout_workspace" >"$TMP_DIR/dirty-checkout.log" 2>&1; then
+  echo "expected dirty Dart checkout to fail" >&2
+  exit 1
+fi
+grep -q "Dart SDK target is a dirty git checkout" "$TMP_DIR/dirty-checkout.log"
+test -d "$dirty_dart/.git"
+test -f "$dirty_dart/untracked.txt"
+
+forbidden_dart_remote_workspace="$TMP_DIR/forbidden-dart-remote"
+make_workspace "$forbidden_dart_remote_workspace"
+git -C "$forbidden_dart_remote_workspace/dart-sdk" remote add origin \
+  https://github.com/dart-lang/sdk.git
+if run_sync "$forbidden_dart_remote_workspace" >"$TMP_DIR/forbidden-dart-remote.log" 2>&1; then
+  echo "expected forbidden Dart SDK remote to fail" >&2
+  exit 1
+fi
+grep -q "Dart SDK source checkout uses forbidden remote fragment" \
+  "$TMP_DIR/forbidden-dart-remote.log"
+
+forbidden_updater_remote_workspace="$TMP_DIR/forbidden-updater-remote"
+make_workspace "$forbidden_updater_remote_workspace"
+git -C "$forbidden_updater_remote_workspace/updater" remote add origin \
+  https://github.com/shorebirdtech/updater.git
+if run_sync "$forbidden_updater_remote_workspace" >"$TMP_DIR/forbidden-updater-remote.log" 2>&1; then
+  echo "expected forbidden updater source remote to fail" >&2
+  exit 1
+fi
+grep -q "updater submodule source checkout uses forbidden remote fragment" \
+  "$TMP_DIR/forbidden-updater-remote.log"
+
+forbidden_updater_url_workspace="$TMP_DIR/forbidden-updater-url"
+make_workspace "$forbidden_updater_url_workspace"
+rm -rf "$forbidden_updater_url_workspace/updater"
+if DART_SRC="$forbidden_updater_url_workspace/dart-sdk" \
+  UPDATER_SRC="$forbidden_updater_url_workspace/missing-updater" \
+  UPDATER_URL=https://github.com/shorebirdtech/updater.git \
+  "$forbidden_updater_url_workspace/scripts/sync_open_sources.sh" \
+    >"$TMP_DIR/forbidden-updater-url.log" 2>&1; then
+  echo "expected forbidden explicit UPDATER_URL to fail" >&2
+  exit 1
+fi
+grep -q "UPDATER_URL points at a forbidden official Shorebird updater remote" \
+  "$TMP_DIR/forbidden-updater-url.log"
+
+echo "sync_open_sources.sh smoke test passed"

scripts/verify_upload_readiness.sh

@@ -0,0 +1,10 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+
+"$ROOT/scripts/verify_ci_workflow.sh" \
+  --require-upload-ready \
+  "$ROOT/.github/workflows/open-shorebird-ci.yml"
+
+echo "upload readiness check passed"

scripts/verify_write_sha256.sh

@@ -0,0 +1,51 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+TMP_DIR="$(mktemp -d "${TMPDIR:-/tmp}/open-shorebird-sha256.XXXXXX")"
+trap 'rm -rf "$TMP_DIR"' EXIT
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+ARTIFACT="$TMP_DIR/artifact.txt"
+SIDECAR="$TMP_DIR/artifact.txt.sha256"
+CUSTOM_SIDECAR="$TMP_DIR/custom.sha256"
+
+printf 'open-shorebird\n' > "$ARTIFACT"
+
+"$ROOT/scripts/write_sha256.sh" "$ARTIFACT"
+
+EXPECTED_HASH="$("$PYTHON_BIN" - "$ARTIFACT" <<'PY'
+import hashlib
+import pathlib
+import sys
+
+print(hashlib.sha256(pathlib.Path(sys.argv[1]).read_bytes()).hexdigest())
+PY
+)"
+EXPECTED_LINE="$EXPECTED_HASH  artifact.txt"
+ACTUAL_LINE="$(cat "$SIDECAR")"
+
+if [[ "$ACTUAL_LINE" != "$EXPECTED_LINE" ]]; then
+  echo "unexpected sha256 sidecar: $ACTUAL_LINE" >&2
+  echo "expected: $EXPECTED_LINE" >&2
+  exit 70
+fi
+
+"$ROOT/scripts/write_sha256.sh" "$ARTIFACT" "$CUSTOM_SIDECAR"
+CUSTOM_LINE="$(cat "$CUSTOM_SIDECAR")"
+
+if [[ "$CUSTOM_LINE" != "$EXPECTED_LINE" ]]; then
+  echo "unexpected custom sha256 sidecar: $CUSTOM_LINE" >&2
+  echo "expected: $EXPECTED_LINE" >&2
+  exit 70
+fi
+
+if "$ROOT/scripts/write_sha256.sh" "$TMP_DIR/missing.txt" >/dev/null 2>&1; then
+  echo "write_sha256.sh unexpectedly succeeded for a missing artifact" >&2
+  exit 70
+fi
+
+echo "write_sha256.sh smoke test passed"

scripts/write_artifact_manifest.py

@@ -0,0 +1,85 @@
+#!/usr/bin/env python3
+"""Write an open Shorebird artifact proxy manifest.
+
+The artifact proxy expects this file at:
+
+  /shorebird/<shorebird-engine-revision>/artifacts_manifest.yaml
+
+It maps a custom Shorebird engine revision back to the upstream Flutter engine
+revision for unchanged artifacts, and lists the artifact paths that should be
+served from the open Shorebird mirror.
+"""
+
+from __future__ import annotations
+
+import argparse
+from pathlib import Path
+import sys
+
+
+DEFAULT_ARTIFACT_OVERRIDES = (
+    "flutter_infra_release/flutter/$engine/android-arm64-release/artifacts.zip",
+    "flutter_infra_release/flutter/$engine/android-arm64-release/symbols.zip",
+    "flutter_infra_release/flutter/$engine/linux-x64-release/artifacts.zip",
+    "flutter_infra_release/flutter/$engine/linux-x64-release/linux-x64-flutter-gtk.zip",
+    "flutter_infra_release/flutter/$engine/ios-release/artifacts.zip",
+    "flutter_infra_release/flutter/$engine/flutter_patched_sdk_product.zip",
+    "flutter_infra_release/flutter/$engine/flutter-web-sdk.zip",
+    "flutter_infra_release/flutter/$engine/darwin-arm64-release/FlutterMacOS.framework.zip",
+)
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser()
+    parser.add_argument(
+        "--flutter-engine-revision",
+        required=True,
+        help="Upstream Flutter engine revision used for non-overridden artifacts.",
+    )
+    parser.add_argument(
+        "--storage-bucket",
+        default="shorebird",
+        help="Bucket/path prefix under the Shorebird artifact mirror.",
+    )
+    parser.add_argument(
+        "--output",
+        type=Path,
+        help="Output path. Writes to stdout when omitted.",
+    )
+    return parser.parse_args()
+
+
+def yaml_quote(value: str) -> str:
+    return "'" + value.replace("'", "''") + "'"
+
+
+def build_manifest(flutter_engine_revision: str, storage_bucket: str) -> str:
+    lines = [
+        f"flutter_engine_revision: {yaml_quote(flutter_engine_revision)}",
+        f"storage_bucket: {yaml_quote(storage_bucket)}",
+        "artifact_overrides:",
+    ]
+    lines.extend(
+        f"  - {yaml_quote(override)}" for override in DEFAULT_ARTIFACT_OVERRIDES
+    )
+    return "\n".join(lines) + "\n"
+
+
+def main() -> int:
+    args = parse_args()
+    manifest = build_manifest(
+        flutter_engine_revision=args.flutter_engine_revision,
+        storage_bucket=args.storage_bucket,
+    )
+
+    if args.output is None:
+        sys.stdout.write(manifest)
+        return 0
+
+    args.output.parent.mkdir(parents=True, exist_ok=True)
+    args.output.write_text(manifest, encoding="utf-8")
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

scripts/write_gclient.sh

@@ -7,8 +7,13 @@ INCLUDE_ENGINE_DEPS="${INCLUDE_ENGINE_DEPS:-0}"
 
 case "$PLATFORM" in
   linux)
-    TARGET_OS='["linux"]'
+    if [[ "$INCLUDE_ENGINE_DEPS" == "1" ]]; then
-    DART_DOWNLOAD_ANDROID_DEPS="False"
+      TARGET_OS='["linux", "android"]'
+      DART_DOWNLOAD_ANDROID_DEPS="True"
+    else
+      TARGET_OS='["linux"]'
+      DART_DOWNLOAD_ANDROID_DEPS="False"
+    fi
     ;;
   macos)
     if [[ "$INCLUDE_ENGINE_DEPS" == "1" ]]; then
@@ -28,13 +33,13 @@ esac
 cat > "$ROOT/.gclient" <<EOF
 solutions = [
   {
-    "name": "dart-sdk-new",
+    "name": "dart-sdk",
-    "url": "https://git.tonycloud.org/dart-lang/sdk.git",
+    "url": "https://github.com/tony-cloud/dart-sdk.git",
     "deps_file": "DEPS",
     "managed": False,
     "custom_deps": {},
     "custom_vars": {
-      "dart_root": "dart-sdk-new",
+      "dart_root": "dart-sdk",
       "download_android_deps": $DART_DOWNLOAD_ANDROID_DEPS,
       "checkout_javascript_engines": False,
       "checkout_benchmarks_internal": False,
@@ -52,7 +57,7 @@ if [[ "$INCLUDE_ENGINE_DEPS" == "1" ]]; then
 solutions = [
   {
     "name": ".",
-    "url": "https://git.tonycloud.org/flutter/flutter.git",
+    "url": "https://github.com/tony-cloud/flutter.git",
     "deps_file": "DEPS",
     "managed": False,
     "custom_deps": {
@@ -77,7 +82,6 @@ solutions = [
       "engine/src/flutter/third_party/dart/third_party/pkg/tools": None,
       "engine/src/flutter/third_party/dart/third_party/pkg/vector_math": None,
       "engine/src/flutter/third_party/dart/third_party/pkg/web": None,
-      "engine/src/flutter/third_party/dart/third_party/pkg/webdev": None,
       "engine/src/flutter/third_party/dart/third_party/pkg/webdriver": None,
       "engine/src/flutter/third_party/dart/third_party/pkg/webkit_inspection_protocol": None,
       "engine/src/flutter/third_party/dart/tools/sdks/dart-sdk": None,

scripts/write_release_manifest.py

@@ -0,0 +1,177 @@
+#!/usr/bin/env python3
+"""Write a JSON manifest for CI release artifacts.
+
+Every non-sidecar file under the input directory must have a sibling
+`<file>.sha256` sidecar in the format written by scripts/write_sha256.py:
+
+  <hex sha256>  <basename>
+"""
+
+from __future__ import annotations
+
+import argparse
+import fnmatch
+import hashlib
+import json
+from pathlib import Path, PurePosixPath
+import sys
+
+
+def digest_file(path: Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as file:
+        for chunk in iter(lambda: file.read(1024 * 1024), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def is_plain_file(path: Path) -> bool:
+    return path.is_file() and not path.is_symlink()
+
+
+def parse_sidecar(path: Path) -> tuple[str, str]:
+    text = path.read_text(encoding="utf-8").strip()
+    parts = text.split()
+    if len(parts) != 2:
+        raise ValueError(f"expected '<sha256>  <filename>', got {text!r}")
+    digest, filename = parts
+    if len(digest) != 64 or any(char not in "0123456789abcdef" for char in digest):
+        raise ValueError(f"invalid sha256 digest {digest!r}")
+    return digest, filename
+
+
+def is_safe_relative_path(path: str) -> bool:
+    if not path or path == ".":
+        return False
+    if "\\" in path or "\x00" in path or path.endswith("/"):
+        return False
+    if any(ord(character) < 32 for character in path):
+        return False
+
+    candidate = PurePosixPath(path)
+    if candidate.is_absolute():
+        return False
+    if any(part in ("", ".", "..") for part in candidate.parts):
+        return False
+    if candidate.parts and ":" in candidate.parts[0]:
+        return False
+    return True
+
+
+def parse_args() -> argparse.Namespace:
+    parser = argparse.ArgumentParser()
+    parser.add_argument("input_dir", type=Path)
+    parser.add_argument("--output", required=True, type=Path)
+    parser.add_argument("--github-sha", default="")
+    parser.add_argument(
+        "--require",
+        action="append",
+        default=[],
+        metavar="GLOB",
+        help="Require at least one artifact path matching this glob. May be repeated.",
+    )
+    return parser.parse_args()
+
+
+def main() -> int:
+    args = parse_args()
+    input_dir = args.input_dir
+    output_path = args.output
+
+    if not input_dir.is_dir():
+        print(f"missing input directory: {input_dir}", file=sys.stderr)
+        return 66
+
+    artifacts = []
+    errors = []
+    for artifact_path in sorted(path for path in input_dir.rglob("*") if path.is_file()):
+        if artifact_path.is_symlink():
+            errors.append(f"{artifact_path.relative_to(input_dir).as_posix()}: symlink artifacts are not allowed")
+            continue
+        if artifact_path.suffix == ".sha256":
+            continue
+        if artifact_path.resolve() == output_path.resolve():
+            continue
+
+        artifact_relative_path = artifact_path.relative_to(input_dir).as_posix()
+        if not is_safe_relative_path(artifact_relative_path):
+            errors.append(f"{artifact_relative_path}: unsafe artifact path")
+            continue
+        if artifact_path.stat().st_size <= 0:
+            errors.append(f"{artifact_relative_path}: empty artifacts are not allowed")
+            continue
+        artifact_relative = PurePosixPath(artifact_relative_path)
+
+        sidecar_path = Path(f"{artifact_path}.sha256")
+        if not is_plain_file(sidecar_path):
+            errors.append(f"{artifact_relative_path}: missing .sha256 sidecar")
+            continue
+
+        actual_digest = digest_file(artifact_path)
+        try:
+            sidecar_digest, sidecar_filename = parse_sidecar(sidecar_path)
+        except ValueError as error:
+            errors.append(f"{sidecar_path.relative_to(input_dir).as_posix()}: {error}")
+            continue
+
+        if sidecar_digest != actual_digest:
+            errors.append(
+                f"{sidecar_path.relative_to(input_dir).as_posix()}: digest mismatch "
+                f"{sidecar_digest} != {actual_digest}"
+            )
+        if sidecar_filename != artifact_path.name:
+            errors.append(
+                f"{sidecar_path.relative_to(input_dir).as_posix()}: filename mismatch "
+                f"{sidecar_filename!r} != {artifact_path.name!r}"
+            )
+
+        artifacts.append(
+            {
+                "path": artifact_relative_path,
+                "artifact_group": artifact_relative.parts[0],
+                "filename": artifact_path.name,
+                "sha256": actual_digest,
+                "size": artifact_path.stat().st_size,
+                "sidecar": sidecar_path.relative_to(input_dir).as_posix(),
+            }
+        )
+
+    orphan_sidecars = []
+    for sidecar_path in sorted(input_dir.rglob("*.sha256")):
+        artifact_path = Path(str(sidecar_path)[: -len(".sha256")])
+        if sidecar_path.is_symlink():
+            orphan_sidecars.append(sidecar_path.relative_to(input_dir).as_posix())
+        elif not is_plain_file(artifact_path):
+            orphan_sidecars.append(sidecar_path.relative_to(input_dir).as_posix())
+    if orphan_sidecars:
+        errors.append(f"orphan .sha256 sidecars: {', '.join(orphan_sidecars)}")
+
+    artifact_paths = [artifact["path"] for artifact in artifacts]
+    for required_glob in args.require:
+        if not any(fnmatch.fnmatchcase(path, required_glob) for path in artifact_paths):
+            errors.append(f"missing required artifact matching {required_glob!r}")
+
+    if errors:
+        print(
+            "release manifest validation failed:\n"
+            + "\n".join(f"  {error}" for error in errors),
+            file=sys.stderr,
+        )
+        return 70
+
+    manifest = {
+        "format_version": 1,
+        "github_sha": args.github_sha,
+        "artifact_count": len(artifacts),
+        "artifacts": artifacts,
+    }
+    output_path.parent.mkdir(parents=True, exist_ok=True)
+    output_path.write_text(
+        json.dumps(manifest, indent=2, sort_keys=True) + "\n",
+        encoding="utf-8",
+    )
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

scripts/write_sha256.py

@@ -0,0 +1,43 @@
+#!/usr/bin/env python3
+"""Write a sha256 sidecar in the common `digest  filename` format."""
+
+from __future__ import annotations
+
+import hashlib
+import pathlib
+import sys
+
+
+def digest_file(path: pathlib.Path) -> str:
+    digest = hashlib.sha256()
+    with path.open("rb") as file:
+        for chunk in iter(lambda: file.read(1024 * 1024), b""):
+            digest.update(chunk)
+    return digest.hexdigest()
+
+
+def main() -> int:
+    if len(sys.argv) not in (2, 3):
+        print("usage: write_sha256.py <artifact> [output]", file=sys.stderr)
+        return 64
+
+    artifact_path = pathlib.Path(sys.argv[1])
+    output_path = (
+        pathlib.Path(sys.argv[2])
+        if len(sys.argv) == 3
+        else pathlib.Path(f"{artifact_path}.sha256")
+    )
+
+    if not artifact_path.is_file():
+        print(f"missing artifact: {artifact_path}", file=sys.stderr)
+        return 66
+
+    output_path.write_text(
+        f"{digest_file(artifact_path)}  {artifact_path.name}\n",
+        encoding="utf-8",
+    )
+    return 0
+
+
+if __name__ == "__main__":
+    raise SystemExit(main())

scripts/write_sha256.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+set -euo pipefail
+
+if [[ "$#" -ne 1 && "$#" -ne 2 ]]; then
+  echo "usage: $0 <artifact> [output]" >&2
+  exit 64
+fi
+
+ROOT="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
+PYTHON_BIN=python3
+if ! command -v "$PYTHON_BIN" >/dev/null 2>&1; then
+  PYTHON_BIN=python
+fi
+
+"$PYTHON_BIN" "$ROOT/scripts/write_sha256.py" "$@"

testapps/license_flavor_patch_test/ios/Runner/SceneDelegate.swift

@@ -2,5 +2,39 @@ import Flutter
 import UIKit
 
 class SceneDelegate: FlutterSceneDelegate {
+  override func scene(
+    _ scene: UIScene,
+    willConnectTo session: UISceneSession,
+    options connectionOptions: UIScene.ConnectionOptions
+  ) {
+    guard let windowScene = scene as? UIWindowScene else {
+      return
+    }
 
+    let project = FlutterDartProject()
+    project.shorebirdAotPatchKeyProvider = { keyIdentifier in
+      guard keyIdentifier == "test-key" else {
+        return nil
+      }
+      let bytes: [UInt8] = [
+        0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+        0x08, 0x09, 0x0a, 0x0b, 0x0c, 0x0d, 0x0e, 0x0f,
+        0x10, 0x11, 0x12, 0x13, 0x14, 0x15, 0x16, 0x17,
+        0x18, 0x19, 0x1a, 0x1b, 0x1c, 0x1d, 0x1e, 0x1f,
+      ]
+      return Data(bytes)
+    }
+
+    let flutterViewController = FlutterViewController(
+      project: project,
+      nibName: nil,
+      bundle: nil
+    )
+    GeneratedPluginRegistrant.register(with: flutterViewController.engine)
+
+    let window = UIWindow(windowScene: windowScene)
+    window.rootViewController = flutterViewController
+    self.window = window
+    window.makeKeyAndVisible()
+  }
 }

testapps/license_flavor_patch_test/shorebird.yaml

@@ -1,6 +1,5 @@
 app_id: license-flavor-patch-test
 aot_patch_key_id: test-key
-aot_patch_key_hex: "000102030405060708090a0b0c0d0e0f101112131415161718191a1b1c1d1e1f"
 aot_patch_base_flavor_id: free
 aot_patch_base_license_type: free
 aot_patch_flavor_id: pro

testapps/license_flavor_patch_test/tool/verify_aot_patch.dart

@@ -4,7 +4,7 @@ import 'dart:io';
 Future<void> main() async {
   final appDir = File.fromUri(Platform.script).parent.parent;
   final workspaceRoot = appDir.parent.parent;
-  final dartRoot = Directory('${workspaceRoot.path}/dart-sdk-new');
+  final dartRoot = Directory('${workspaceRoot.path}/dart-sdk');
   final patchBuildDir = _resolvePatchBuildDir(dartRoot);
   final toolWorkspace = Directory('${workspaceRoot.path}/shorebird');
   final workDir = Directory('${appDir.path}/build/open_aot_patch_verify');