diff --git a/pkg/test_runner/lib/src/compiler_configuration.dart b/pkg/test_runner/lib/src/compiler_configuration.dart
index 6b08ea01d57..597fe79d4a4 100644
--- a/pkg/test_runner/lib/src/compiler_configuration.dart
+++ b/pkg/test_runner/lib/src/compiler_configuration.dart
@@ -25,12 +25,30 @@ List<String> _replaceDartFiles(List<String> list, String replacement) {
 /// list allows the result of calling this to be spread into another list.
 List<String> _experimentsArgument(
     TestConfiguration configuration, TestFile testFile) {
-  if (configuration.experiments.isEmpty && testFile.experiments.isEmpty) {
+  var experiments = {
+    ...configuration.experiments,
+    ...testFile.experiments,
+    if (configuration.nnbdMode != NnbdMode.legacy)
+      'non-nullable',
+  };
+  if (experiments.isEmpty) {
     return const [];
   }
 
-  var experiments = {...configuration.experiments, ...testFile.experiments};
-  return ["--enable-experiment=${experiments.join(',')}"];
+  return ['--enable-experiment=${experiments.join(',')}'];
+}
+
+List<String> _nnbdModeArgument(TestConfiguration configuration) {
+  switch (configuration.nnbdMode) {
+    case NnbdMode.legacy:
+      return [];
+    case NnbdMode.strong:
+      return ['--sound-null-safety'];
+    case NnbdMode.weak:
+      return ['--no-sound-null-safety'];
+  }
+
+  throw 'unreachable';
 }
 
 /// Grouping of a command with its expected result.
@@ -175,6 +193,7 @@ class NoneCompilerConfiguration extends CompilerConfiguration {
       else if (_configuration.hotReloadRollback)
         '--hot-reload-rollback-test-mode',
       ...vmOptions,
+      ..._nnbdModeArgument(_configuration),
       ...testFile.sharedOptions,
       ..._configuration.sharedOptions,
       ..._experimentsArgument(_configuration, testFile),
@@ -426,13 +445,18 @@ class Dart2jsCompilerConfiguration extends Dart2xCompilerConfiguration {
       ..._configuration.sharedOptions,
       ..._experimentsArgument(_configuration, testFile),
       ...testFile.dart2jsOptions,
+      ..._nnbdModeArgument(_configuration),
       ...args
     ];
   }
 
   CommandArtifact computeCompilationArtifact(String tempDir,
       List<String> arguments, Map<String, String> environmentOverrides) {
-    var compilerArguments = [...arguments, ..._configuration.dart2jsOptions];
+    var compilerArguments = [
+      ...arguments,
+      ..._configuration.dart2jsOptions,
+      ..._nnbdModeArgument(_configuration),
+    ];
 
     // TODO(athom): input filename extraction is copied from DDC. Maybe this
     // should be passed to computeCompilationArtifact, instead?
@@ -729,9 +753,14 @@ class PrecompilerCompilerConfiguration extends CompilerConfiguration
   static const String ndkPath = "third_party/android_tools/ndk";
   String get abiTriple => _isArm || _isArmX64
       ? "arm-linux-androideabi"
-      : _isArm64 ? "aarch64-linux-android" : null;
-  String get host =>
-      Platform.isLinux ? "linux" : Platform.isMacOS ? "darwin" : null;
+      : _isArm64
+          ? "aarch64-linux-android"
+          : null;
+  String get host => Platform.isLinux
+      ? "linux"
+      : Platform.isMacOS
+          ? "darwin"
+          : null;
 
   Command computeAssembleCommand(String tempDir, List arguments,
       Map<String, String> environmentOverrides) {
@@ -1104,6 +1133,7 @@ abstract class VMKernelCompilerMixin {
           arguments.contains('--enable-asserts') ||
           arguments.contains('--enable_asserts'))
         '--enable-asserts',
+      ..._nnbdModeArgument(_configuration),
       ..._configuration.genKernelOptions,
     ];
 
diff --git a/tools/bots/test_matrix.json b/tools/bots/test_matrix.json
index 88ab3c42dbe..bb2918c669c 100644
--- a/tools/bots/test_matrix.json
+++ b/tools/bots/test_matrix.json
@@ -398,10 +398,7 @@
         "enable-asserts": true,
         "mode": "release",
         "runtime": "vm",
-        "timeout": 240,
-        "enable-experiment": [
-          "non-nullable"
-        ]
+        "timeout": 240
       }
     },
     "analyzer-unittest-asserts-(debug|product|release)-(linux|mac|win)": {
@@ -516,12 +513,6 @@
     "dart2js-weak-(linux|mac|win)-x64-d8": {
       "options": {
         "builder-tag": "dart2js-weak",
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "dart2js-options": [
-          "--no-sound-null-safety"
-        ],
         "use-sdk": true
       }
     },
@@ -576,11 +567,7 @@
     "dart2js-hostasserts-weak-(linux|win)-x64-(d8|chrome)": {
       "options": {
         "builder-tag": "dart2js-weak",
-        "enable-experiment": [
-          "non-nullable"
-        ],
         "dart2js-options": [
-          "--no-sound-null-safety",
           "--libraries-spec=sdk/lib/libraries.json",
           "--platform-binaries=out/ReleaseX64/"
         ],
@@ -591,11 +578,7 @@
     "dart2js-hostasserts-weak-mac-x64-(d8|chrome)": {
       "options": {
         "builder-tag": "dart2js-weak",
-        "enable-experiment": [
-          "non-nullable"
-        ],
         "dart2js-options": [
-          "--no-sound-null-safety",
           "--libraries-spec=sdk/lib/libraries.json",
           "--platform-binaries=xcodebuild/ReleaseX64/"
         ],
@@ -606,11 +589,7 @@
     "dart2js-hostasserts-strong-(linux|win)-x64-(d8|chrome)": {
       "options": {
         "builder-tag": "dart2js-strong",
-        "enable-experiment": [
-          "non-nullable"
-        ],
         "dart2js-options": [
-          "--sound-null-safety",
           "--libraries-spec=sdk/lib/libraries.json",
           "--platform-binaries=out/ReleaseX64/"
         ],
@@ -621,11 +600,7 @@
     "dart2js-hostasserts-strong-mac-x64-(d8|chrome)": {
       "options": {
         "builder-tag": "dart2js-strong",
-        "enable-experiment": [
-          "non-nullable"
-        ],
         "dart2js-options": [
-          "--sound-null-safety",
           "--libraries-spec=sdk/lib/libraries.json",
           "--platform-binaries=xcodebuild/ReleaseX64/"
         ],
@@ -710,115 +685,49 @@
     },
     "dartkp-weak-asserts-(linux|mac)-(debug|product|release)-x64": {
       "options": {
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "gen-kernel-options": [
-          "--no-sound-null-safety"
-        ],
         "enable-asserts": true,
-        "vm-options": [
-          "--no-sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
     "dartkp-weak-asserts-(linux|mac)-(debug|product|release)-simarm64": {
       "options": {
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "gen-kernel-options": [
-          "--no-sound-null-safety"
-        ],
         "enable-asserts": true,
         "use-elf": true,
-        "vm-options": [
-          "--no-sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
     "dartkp-weak-asserts-win-(debug|product|release)-(simarm64|x64)": {
       "options": {
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "gen-kernel-options": [
-          "--no-sound-null-safety"
-        ],
         "enable-asserts": true,
         "use-elf": true,
-        "vm-options": [
-          "--no-sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
     "dartk-weak-asserts-(linux|mac|win)-(debug|product|release)-x64": {
       "options": {
-        "enable-experiment": [
-          "non-nullable"
-        ],
         "enable-asserts": true,
-        "vm-options": [
-          "--no-sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
     "dartk-strong-(linux|mac|win)-(debug|product|release)-x64": {
       "options": {
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "vm-options": [
-          "--sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
     "dartkp-strong-(linux|mac)-(debug|product|release)-x64": {
       "options": {
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "gen-kernel-options": [
-          "--sound-null-safety"
-        ],
-        "vm-options": [
-          "--sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
     "dartkp-strong-(linux|mac)-(debug|product|release)-simarm64": {
       "options": {
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "gen-kernel-options": [
-          "--sound-null-safety"
-        ],
         "use-elf": true,
-        "vm-options": [
-          "--sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
     "dartkp-strong-win-(debug|product|release)-(simarm64|x64)": {
       "options": {
         "use-elf": true,
-        "enable-experiment": [
-          "non-nullable"
-        ],
-        "gen-kernel-options": [
-          "--sound-null-safety"
-        ],
-        "vm-options": [
-          "--sound-null-safety"
-        ],
         "builder-tag": "vm_nnbd"
       }
     },
@@ -868,9 +777,6 @@
       "options": {
         "checked": true,
         "use-sdk": true,
-        "enable-experiment": [
-          "non-nullable"
-        ],
         "enable-asserts": true
       }
     },
@@ -878,9 +784,6 @@
       "options": {
         "checked": true,
         "use-sdk": true,
-        "enable-experiment": [
-          "non-nullable"
-        ],
         "enable-asserts": true
       }
     },
@@ -891,18 +794,12 @@
     },
     "cfe-weak-(linux|mac|win)": {
       "options": {
-        "compiler": "fasta",
-        "enable-experiment": [
-          "non-nullable"
-        ]
+        "compiler": "fasta"
       }
     },
     "cfe-strong-(linux|mac|win)": {
       "options": {
-        "compiler": "fasta",
-        "enable-experiment": [
-          "non-nullable"
-        ]
+        "compiler": "fasta"
       }
     },
     "analyzer-(linux|mac|win)": {
@@ -922,20 +819,14 @@
       "options": {
         "compiler": "dart2analyzer",
         "enable-asserts": true,
-        "use-sdk": true,
-        "enable-experiment": [
-          "non-nullable"
-        ]
+        "use-sdk": true
       }
     },
     "analyzer-asserts-weak-(linux|mac|win)": {
       "options": {
         "compiler": "dart2analyzer",
         "enable-asserts": true,
-        "use-sdk": true,
-        "enable-experiment": [
-          "non-nullable"
-        ]
+        "use-sdk": true
       }
     }
   },