SDK Compatibility Policy

Versioning

• SDK packages use Semantic Versioning (MAJOR.MINOR.PATCH).
• Breaking API changes require major version bumps.
• New features are minor bumps.
• Bug fixes are patch bumps.

Support Window

• Active support for the latest major + previous major.
• Security fixes are backported for previous major for 90 days.

Upgrade Guarantees

• @last1id/sdk and @last1id/login-button document migration notes for every major and minor release.
• Deprecated APIs remain available for at least one minor cycle before removal (except security-critical removals).

Release Artifacts

• npm package tarballs
• changelog entry
• migration notes
• updated reference examples

Required Compatibility Tests

• authorize URL generation with PKCE
• token exchange for authorization code grant
• refresh token rotation
• login-button redirect behavior