Deprecation and Migration
Code is a liability — disciplined removal, Hyrum's law, expand/contract schema migrations
- What
- Code is a liability — disciplined removal, Hyrum's law, expand/contract schema migrations
- Cost
- Free
- Needs
- none
- Install
- Copy the installer prompt below into your Muse — your agent does the rest.
Curated by Skill Harbor — the discipline most engineering organizations lack: removing code. Code is a liability, not an asset — every line carries maintenance cost, and when the same functionality can be delivered with less code, the old code should go. Covers the deprecation decision (does it still provide unique value? how many consumers? does a replacement exist? what's the migration cost? what's the cost of NOT deprecating?), Hyrum's Law (with enough users, every observable behavior — bugs included — becomes depended on, so deprecation requires active migration, not just announcement), designing for removal from day one (clean interfaces, feature flags, minimal surface area), and zero-downtime production schema migrations (expand/contract). Not verified against any particular codebase — a methodology skill. By @addyosmani, listed here with credit to its creator. Skill Harbor never reviews the code, review it yourself before use.
Version:
Install
Prerequisites: none Install "Deprecation and Migration" for me. Code is a liability — disciplined removal, Hyrum's law, expand/contract schema migrations Repository: https://github.com/addyosmani/agent-skills/blob/main/skills/deprecation-and-migration/SKILL.md 1. Fetch the SKILL.md file for the addyosmani-deprecation-and-migration skill from the repository into a temporary folder and summarize what it does in one or two sentences. 2. Safety check: review the SKILL.md and scripts for anything suspicious (unexpected network calls, shell commands, credential harvesting). This repo should contain zero secrets in code, credentials only via the secure vault, allowed hosts declared in the SKILL.md. Verify that holds here; STOP on any red flag and tell me. 3. Install it as a skill: copy SKILL.md and its helper files into the agent's skills directory, in a folder named "addyosmani-deprecation-and-migration". 4. Verify with no network calls: frontmatter valid, files in place. 5. Report what was installed, where, and what I still need to do myself (e.g. any accounts, API keys, or CLI tools mentioned in the prerequisites above). GitHub is optional: if I have a GitHub account or the gh CLI, you may use it; otherwise public access is fine. Never require it unless it's in the prerequisites above. Rules: don't touch anything outside the temp folder and the install target. Never ask me to paste secrets in chat — credentials go through the secure vault or environment variables. If anything looks off, stop and ask me.
Questions
How do I install a build?
Every product page includes a copy-paste install prompt. Paste it into your Muse and it sets the build up for you — no manual configuration.
Where does my money go?
Straight to the seller. Skill Harbor never processes payments: checkout happens on the seller’s own page, usually Stripe.
What does the ✓ next to a creator’s name mean?
It means we confirmed the identity of the person behind the listing. It says nothing about the code itself — always check a build before installing it.