How Strait manages immutable migrations and baseline bootstraps.

Current Policy

• Existing numbered migrations are immutable once merged.
• Never rewrite or squash already-applied migrations in deployed environments.
• Backward/forward compatibility is maintained by additive migrations.

Consolidation Plan for New Environments

To speed up fresh installs while preserving safety for existing deployments:

1. Keep historical migrations (000001..current) for upgrades.
2. Introduce periodic baseline snapshot migrations for fresh databases only.
3. Keep incremental migrations after each baseline for active development.

Example baseline pattern:

• 001000_baseline_schema.up.sql — complete schema at release cut
• 001001_*.sql onward — normal incremental migrations

Operational Rules

• Existing environments:
  • Continue applying incremental migrations in order.
  • Never skip historical migration state.
• New environments:
  • Bootstrap from baseline + subsequent increments.

Tooling Notes

• Baseline generation should be automated from a fully migrated reference DB.
• CI should test both paths:
  1. empty DB through full historical chain
  2. baseline through latest increments

Safety Checklist Before Releasing a Baseline

• Schema diff against reference DB is empty
• Integration/E2E pass on baseline bootstrap path
• Integration/E2E pass on historical upgrade path
• Rollback scripts verified for latest increment set