From ce
Guides safe code migrations for DB schemas, APIs, framework upgrades, library swaps with backward compatibility, reversibility, testing, and rollbacks.
How this skill is triggered — by the user, by Claude, or both
Slash command
/ce:migrating-codeThe summary Claude sees in its skill listing — used to decide when to auto-load this skill
1. **Never break production** - Backward compatible until fully rolled out
- [ ] Pre-Migration: Read changelog, identify breaking changes, ensure test coverage
- [ ] During: Small steps, test each, monitor errors, rollback ready
- [ ] Post: Verify tests, check metrics, remove scaffolding, update docs
| Operation | Pattern |
|---|---|
| Add column | Add nullable first → backfill → add constraints |
| Remove column | Stop writes → deploy code that doesn't read → drop column |
| Rename column | Add new → dual-write → backfill → switch reads → drop old |
| Change type | New column → dual-write → migrate in batches → switch → drop |
Never: Add NOT NULL without defaults to tables with data.
{
"data": {},
"_warnings": [{
"code": "DEPRECATED_ENDPOINT",
"message": "Use /api/v2/users instead",
"sunset": "2025-06-01"
}]
}
// Wrap library usage
// lib/date.ts
import moment from 'moment';
export const formatDate = (date: Date, format: string) =>
moment(date).format(format);
// Migration: just change the adapter
import { format } from 'date-fns';
export const formatDate = (date: Date, fmt: string) =>
format(date, fmt);
Use feature flags:
if (featureFlags.useNewSystem) {
return newService.process(order);
} else {
return legacyService.process(order);
}
Roll out: 1% → 10% → 50% → 100% → remove flag
Avoid:
Do:
npx claudepluginhub rileyhilliard/claude-essentials --plugin cePlans and executes database, framework, and dependency migrations with breaking change analysis, phased rollout, and rollback procedures.
Guides safe database schema changes and code migrations with zero-downtime strategies including backfills, dual-writes, feature flags, and Strangler Fig pattern.
Safe schema migrations, backward compatibility, zero-downtime deployments, and rollback strategies.