deprecation-and-migration
Manages deprecation and migration. Use when removing old systems, APIs, or features. Use when migrating users from one implementation to another. Use when deciding whether to maintain or sunset existing code.
Best for engineering organizations m…Works with GitHubLow risk
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@addyosmani- language
- Shell
★17kstars
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Apr 18, 2026
✦overview.md
Use Cases
- →Replacing an old system, API, or library with a new one
- →Sunsetting a feature that's no longer needed
- →Consolidating duplicate implementations
- →Removing dead code that nobody owns but everybody depends on
- →Planning the lifecycle of a new system (deprecation planning starts at design time)
- →Deciding whether to maintain a legacy system or invest in migration
Best for
- ✓engineering organizations managing technical debt
- ✓teams replacing legacy systems
name
deprecation-and-migration
description
Manages deprecation and migration. Use when removing old systems, APIs, or features. Use when migrating users from one implementation to another. Use when deciding whether to maintain or sunset existing code.
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.
When to Use
- Replacing an old system, API, or library with a new one
- Sunsetting a feature that's no longer needed
- Consolidating duplicate implementations
- Removing dead code that nobody owns but everybody depends on
- Planning the lifecycle of a new system (deprecation planning starts at design time)
- Deciding whether to maintain a legacy system or invest in migration
Core Principles
Code Is a Liability
$install
1-click copynpx skills add addyosmani/agent-skills --skill deprecation-and-migrationSafety assessment
★
Clarity score
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1/ 5
poorThe SKILL.md content is hard to understand and quite ambiguous.
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Actionability score
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1/ 5
not actionableThe SKILL.md is hard to act on; an agent would not know what to do.