Dart package:meta

Use package:meta as an API-contract and static-analysis tool, not as annotation decoration and not as a general runtime optimization mechanism.

Operating hierarchy

When expressing a contract, prefer the strongest accurate mechanism in this order:

Dart language guarantee
        ↓
Architecture / real privacy or package boundary
        ↓
Analyzer-enforced metadata contract
        ↓
Lint-enforced convention
        ↓
Documentation-only intent