music_library/backlog/completed/ml-37 - Fix-production-migration-strategy-mismatch.md

id, title, status, assignee, created_date, labels, dependencies, references, priority

id	title	status	assignee	created_date	labels	dependencies	references	priority
ML-37	Fix production migration strategy mismatch	Done		2026-04-20 08:53			https://github.com/cloud8421/music_library/issues/141	high

Description

GitHub: created 2026-03-30 · updated 2026-03-30 · closed 2026-03-30

Summary

Production releases are configured to skip boot-time migrations even though the codebase and docs state that migrations run automatically on startup.

Why This Matters

A deploy can start successfully against an outdated schema, creating a real risk of runtime failures or subtle data corruption after deploys.

Evidence

• MusicLibrary.Application wires Ecto.Migrator with skip: skip_migrations?().
• skip_migrations?/0 returns true whenever RELEASE_NAME is set (the release case).
• rel/overlays/bin/server only starts the release and does not run rel/overlays/bin/migrate.
• scripts/prod/deploy.hurl triggers a deploy and health checks, but does not invoke the migrate script.
• docs/architecture.md and docs/production-infrastructure.md both claim migrations run automatically on boot.

Affected Files

• lib/music_library/application.ex
• rel/overlays/bin/server
• rel/overlays/bin/migrate
• docs/architecture.md
• docs/production-infrastructure.md

Acceptance Criteria

• Production deploys cannot start on an unmigrated schema.
• The documented migration strategy matches the implemented one.
• There is at least one automated check covering the chosen behavior.

• #1 Production deploys cannot start on an unmigrated schema.
• #2 The documented migration strategy matches the implemented one.
• #3 There is at least one automated check covering the chosen behavior.