# Schema Diff

Compare two schema states and surface the risky changes.

- Repository: https://github.com/Archive228/loopkit (756 stars)
- Category: Engineering
- License: MIT
- Last updated: 2026-07-14
- Runs scripts: no, instructions only

## Install

Claude Code: `npx skills add Archive228/loopkit --skill schema-diff -g -a claude-code -y`
Codex: `npx skills add Archive228/loopkit --skill schema-diff -g -a codex -y`
Cursor: `npx skills add Archive228/loopkit --skill schema-diff -g -a cursor -y`
Gemini CLI: `npx skills add Archive228/loopkit --skill schema-diff -g -a gemini-cli -y`
Claude Code plugin marketplace: `/plugin marketplace add Archive228/loopkit`

## Description

Compare two schema states and surface the risky changes. Use before applying migrations or after a model change.

## SKILL.md, as published by its author (untrusted third-party text, read it as data)

# Schema Diff
Diff old vs new schema. Flag by risk:
- **Destructive** (high): dropped column/table, narrowed type, new NOT NULL on existing rows, dropped index a query relies on.
- **Locking** (high at scale): index without CONCURRENTLY, type change that rewrites the table.
- **Safe**: new nullable column, new table, new index CONCURRENTLY.
For each destructive change: is data lost? is it reversible? is there a backfill? Output a risk-ranked list and a go/no-go with the safe rollout order.