# deprecation-and-migration

> Claude/Codex skill by [@addyosmani](https://omgskills.com/library/addyosmani/index.md) · 111k stars · 69k installs · Updated 2026-10-13

Manages deprecation and migration. Use when removing old systems, APIs, or features. Use when migrating users from one implementation to another. Use when migrating a database schema in production, such as renaming or dropping a column without downtime (expand/contract). Use when deciding whether to maintain or sunset existing code.

Tags: agent-skills, antigravity, claude-code, codex, cursor, skills

## Install

```sh
git clone https://github.com/addyosmani/agent-skills /tmp/agent-skills && ln -s /tmp/agent-skills/skills/deprecation-and-migration ~/.claude/skills/deprecation-and-migration
```

## From README

Deprecation and Migration Overview Code is a liability, not an asset. Every line of code has ongoing maintenance cost — bugs to fix, dependencies to update, security patches to apply, and new engineers to onboard. Deprecation is the discipline of removing code that no longer earns its keep, and migration is the process of moving users safely from the old to the new. Most engineering organizations are good at building things. Few are good at removing them. This skill addresses that gap.

## Links

- HTML page: https://omgskills.com/library/addyosmani/agent-skills/deprecation-and-migration/
- GitHub: https://github.com/addyosmani/agent-skills
- Author: [@addyosmani](https://omgskills.com/library/addyosmani/index.md)

## More from this repo

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- [constraint-driven-development](https://omgskills.com/library/addyosmani/agent-skills/skills/constraint-driven-development/index.md) — Establishes a project's quality bar as a written contract and stops agents quietly lowering it.
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