Database Migrations taste

# Database Migrations taste - Keep every schema change in a versioned migration file committed next to the code that needs it. Confidence: 0.95 - Write migrations in plain SQL rather than ORM-generated diffs you have not read. Confidence: 0.80 - Never edit a migration that has already run in a shared environment; add a new one instead. Confidence: 0.95 - Use the expand and contract pattern: add the new column, backfill, switch reads, then drop the old column in a later release. Confidence: 0.90 ...