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BreakingHigh impactOfficial migration guidesince 3.35.0landed 3.33.0-1.0.pre-1416

$FLUTTER_ROOT/version replaced by $FLUTTER_ROOT/bin/cache/flutter.version.json

Framework · Official source

What changed?

The `flutter` tool will no longer output the `$FLUTTER_ROOT/version` metadata file, and only output `$FLUTTER_ROOT/bin/cache/flutter.version.json`.

Will this affect my application?

Who is affected
Applications and packages relying on the previous behaviour or signature.
Practical impact
Behaviour or API differences that can break builds or change runtime behaviour.
What action should I take?
Follow the official migration guide below, update affected call sites, run `dart fix --apply` where a fix is available, then run your tests.

How do I migrate safely?

Official migration guide (excerpt, © The Flutter Authors, CC BY 3.0)

Most Flutter developers don't parse or use this file, but custom tools or CI configurations might.

For example, the Flutter team's own api.flutter.dev generation script:

final File versionFile = File('version');
final String version = versionFile.readAsStringSync();

Was updated in [172601][PR 172601] to:

final File versionFile = File(path.join(checkoutPath, 'bin', 'cache', 'flutter.version.json'));
final String version = () {
  final Map<String, Object?> json =
      jsonDecode(versionFile.readAsStringSync()) as Map<String, Object?>;
  return json['flutterVersion']! as String;
}();

To temporarily opt-out of $FLUTTER_ROOT/version no longer being emitted:

flutter config --no-enable-omit-legacy-version-file
Migration assistantAI-generated · grounded in cited sources
AI explanations are not configured
Set AI_PROVIDER (for example to openai-compatible with a local Ollama or LM Studio endpoint) to enable grounded explanations. Everything else on this page works without an AI provider.

Evidence & verification

Official migration guide·Verified classification (95%)

Listed in the official breaking-changes index (docs.flutter.dev/release/breaking-changes).

An official announcement or migration guide documents an intended behaviour or API change. A verified source change (git diff) shows code changed but does not by itself prove a public API is breaking. AI interpretations are labelled and never used to classify a change.

Source commit
b3045439b7c0
Source last updated
Oct 21, 2026
Last synchronized
Oct 21, 2026
Publication status
published
Publication history
  • Oct 21, 2026, 8:31 PM: new → published (ingestion) — Backed by an official breaking-change/migration guide.
AI explanationAI-generated · grounded in cited sources
AI explanations are not configured
Set AI_PROVIDER (for example to openai-compatible with a local Ollama or LM Studio endpoint) to enable grounded explanations. Everything else on this page works without an AI provider.
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