Safe Database Migration Patterns
affaan-m/ECC
Rules and examples for safe, reversible schema changes in production: zero-downtime column and index changes, large data backfills and ORM migration workflows.
Implementation details for EF Core migrations. An agent skill from dotnet/efcore.
OfficialMITAuto-check passed
Install Migrations
$ npx skills add dotnet/efcore --skill migrations -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install dotnet/efcore migrations --agent claude-codeProject scope by default; add --scope user for a personal install. Needs GitHub CLI 2.90.0 or later (public preview).
$ git clone --depth 1 https://github.com/dotnet/efcore.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/migrations .claude/skills/migrations && rm -rf skills-srcUse ~/.claude/skills/ instead of .claude/skills for a personal install. The folder must contain SKILL.md.
Claude Code skills documentation · loads skills from .claude/skills/
Install the "migrations" agent skill from https://github.com/dotnet/efcore/tree/main/.agents/skills/migrations into .claude/skills/migrations/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "migrations", then confirm the skill loads.Claude Code copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$skill-installer install https://github.com/dotnet/efcore/tree/main/.agents/skills/migrationsType this inside Codex. $skill-installer <name> installs a curated skill from openai/skills. The installer writes to $CODEX_HOME/skills (default ~/.codex/skills). Restart Codex if the skill does not show up.
$ npx skills add dotnet/efcore --skill migrations -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install dotnet/efcore migrations --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/dotnet/efcore.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/migrations .agents/skills/migrations && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "migrations" agent skill from https://github.com/dotnet/efcore/tree/main/.agents/skills/migrations into .agents/skills/migrations/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "migrations", then confirm the skill loads.Codex copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add dotnet/efcore --skill migrations -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install dotnet/efcore migrations --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/dotnet/efcore.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/migrations .cursor/skills/migrations && rm -rf skills-srcUse ~/.cursor/skills/ instead of .cursor/skills for a personal install.
Cursor skills documentation · loads skills from .cursor/skills/, .agents/skills/, .claude/skills/, .codex/skills/
Install the "migrations" agent skill from https://github.com/dotnet/efcore/tree/main/.agents/skills/migrations into .cursor/skills/migrations/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "migrations", then confirm the skill loads.Cursor copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gemini skills install https://github.com/dotnet/efcore.git --path .agents/skills/migrations--scope user (default) or --scope workspace; --path is the subfolder of the repo that holds the skill; --consent skips the security confirmation prompt.
$ npx skills add dotnet/efcore --skill migrations -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install dotnet/efcore migrations --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/dotnet/efcore.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/migrations .gemini/skills/migrations && rm -rf skills-srcUse ~/.gemini/skills/ instead of .gemini/skills for a personal install, then run /skills reload.
Gemini CLI skills documentation · loads skills from .gemini/skills/, .agents/skills/
Install the "migrations" agent skill from https://github.com/dotnet/efcore/tree/main/.agents/skills/migrations into .gemini/skills/migrations/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "migrations", then confirm the skill loads.Gemini CLI copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ gh skill install dotnet/efcore migrationsInstalls for Copilot at project scope by default; add --scope user for a personal install. Preview a skill first with gh skill preview. Needs GitHub CLI 2.90.0 or later (public preview).
$ npx skills add dotnet/efcore --skill migrations -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/dotnet/efcore.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/migrations .github/skills/migrations && rm -rf skills-srcUse ~/.copilot/skills/ instead of .github/skills for a personal install. Commit .github/skills so cloud agent and code review can use it.
GitHub Copilot skills documentation · loads skills from .github/skills/, .claude/skills/, .agents/skills/
Install the "migrations" agent skill from https://github.com/dotnet/efcore/tree/main/.agents/skills/migrations into .github/skills/migrations/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "migrations", then confirm the skill loads.GitHub Copilot copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
$ npx skills add dotnet/efcore --skill migrations -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install dotnet/efcore migrations --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/dotnet/efcore.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/migrations .opencode/skills/migrations && rm -rf skills-srcUse ~/.config/opencode/skills/ instead of .opencode/skills for a personal install.
OpenCode skills documentation · loads skills from .opencode/skills/, .claude/skills/, .agents/skills/
Install the "migrations" agent skill from https://github.com/dotnet/efcore/tree/main/.agents/skills/migrations into .opencode/skills/migrations/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "migrations", then confirm the skill loads.OpenCode copies the folder itself, the same result as the manual copy. Check what it changed before you commit it.
Facts
- Skill name
migrations- GitHub stars
- 15k
- Token cost
- ~374 tokens
- SKILL.md length
- 105 words
- Files
- 1
- Skills in repo
- 17
- Repo updated
- First seen
- Licence
- MIT
At a glance
Implementation details for EF Core migrations. An agent skill from dotnet/efcore.
- Changing MigrationsSqlGenerator
- SKILL.md covers Pipeline, Model Snapshot and Testing
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
- Migration operations
What it does
Migrations is an agent skill from dotnet/efcore, published by the product's own GitHub organization. Implementation details for EF Core migrations. Use when changing MigrationsSqlGenerator, model diffing, migration operations, HistoryRepository, the Migrator or related classes.
Its SKILL.md is about 370 tokens, which your agent loads only when the skill is triggered. It is a single SKILL.md file with no bundled scripts.
The repository describes itself as: EF Core is a modern object-database mapper for .NET. It supports LINQ queries, change tracking, updates, and schema migrations. The licence is MIT.
When your agent uses it
- Changing MigrationsSqlGenerator
- Migration operations
- HistoryRepository
- Related classes
Example prompts
- “/migrations”
What it can do on your machine
Read from SKILL.md and the folder at commit 7adff35. It shows what the files ask for, not the result of running them.
Tool permissions
Pre-approves nothing: there is no allowed-tools line, so your agent's usual permission prompts apply.
From allowed-tools in the SKILL.md frontmatter.
Runs code
No scripts in the folder and no shell commands in SKILL.md.
From the folder's file list and the shell code blocks in SKILL.md.
Network
No URLs in SKILL.md.
From URLs in SKILL.md, links to its own repository left out.
Credentials
Names no API keys, tokens, secrets or passwords.
From names ending in _API_KEY, _TOKEN, _SECRET, _KEY or _PASSWORD in SKILL.md.
Context cost
Migrations loads about 374 tokens when it runs. Until then it costs about 47 tokens; SKILL.md has 105 words of instructions outside code blocks.
Estimates: characters ÷ 4, the usual rule of thumb; real counts depend on the model's tokenizer. Scripts and assets cost tokens only if the agent reads them.
Safety
Auto-check passed
The automated check found no risky patterns in SKILL.md.
Automated static check — not a guarantee. Review scripts before installing. It scans the text of SKILL.md for risky patterns (piping downloads into a shell, reading credential files, hidden Unicode, destructive commands); files beside SKILL.md are not scanned.
SKILL.md
The full file from dotnet/efcore at commit 7adff35, republished under its MIT licence (© dotnet). 105 words, ~374 tokens.
Download SKILL.mdSave it as
.claude/skills/migrations/SKILL.md (or your agent's skills folder).- name
- migrations
- description
- Implementation details for EF Core migrations. Use when changing MigrationsSqlGenerator, model diffing, migration operations, HistoryRepository, the Migrator or related classes.
- user-invocable
- false
Migrations
Pipeline
Add migration: MigrationsScaffolder.ScaffoldMigration() → MigrationsModelDiffer.GetDifferences() → list of MigrationOperation → CSharpMigrationsGenerator and CSharpSnapshotGenerator produce Up/Down/Snapshot code
Apply migration: Migrator.MigrateAsync() → reads __EFMigrationsHistory → per pending: MigrationsSqlGenerator.Generate(operations) → MigrationCommandExecutor executes
Model Snapshot
- Model snapshots use
typeof(Dictionary<string, object>)(property bag format), not the actual CLR type. When examining theClrTypein a snapshot, don't assume it matches the real entity type. SnapshotModelProcessor.Process()is used at design-time to fixup older model snapshots for backward compatibility.MigrationsModelDifferuses provider-agnostic structural comparison between relational models to determine what migration operations are necessary.
Testing
Migration operation tests: test/EFCore.Relational.Tests/Migrations/. Functional tests: test/EFCore.{Provider}.FunctionalTests/Migrations/. Model differ tests: test/EFCore.Relational.Tests/Migrations/Internal/MigrationsModelDifferTest*.cs.
To simulate a snapshot model use ModelBuilder calls without conventions.
© dotnet, MIT. Rendered from Markdown: HTML in the file is shown as text, images as links, and headings moved down two levels. Raw file
Files
Just SKILL.md in .agents/skills/migrations of dotnet/efcore.
Open the folder on GitHubat commit 7adff35
Compare with similar skills
Migrations next to the 5 skills that share the most tags, products or categories with it. Stars are the repository's; “used in” counts other GitHub owners with a copy.
| Skill | Stars | Used in | Tokens | Auto-check | Licence | Repo updated |
|---|---|---|---|---|---|---|
| Migrations this skilldotnet/efcore | 15k | — | ~374 | Automated safety check: Pass | MIT | |
| Safe Database Migration Patternsaffaan-m/ECC | 274k | — | ~3.3k | Automated safety check: Pass | MIT | |
| Database Migrationsaffaan-m/ECC | 274k | 4 repos | ~3k | Automated safety check: Pass | MIT | |
| Reversible MigrationJuliusBrussee/caveman | 110k | 1 repos | ~196 | Automated safety check: Pass | Apache-2.0 | |
| Database Migrationsaffaan-m/ECC | 274k | 1 repos | ~2.4k | Automated safety check: Pass | MIT | |
| Migrationkortix-ai/suna | 20k | — | ~1.2k | Automated safety check: Pass | Custom licence |
Similar skills
Database Migrations
affaan-m/ECC
Safe, reversible database migration patterns: forward-only production changes, expand-contract zero-downtime renames, concurrent indexes, batched backfills, and per-tool workflows for PostgreSQL…
Reversible Migration
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Implement reversible compatibility-safe transitions. Use for schema, data, API, protocol, configuration, or dependency migrations requiring rollback and…
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Şema değişiklikleri, veri migration'ları, rollback'ler ve PostgreSQL, MySQL ve yaygın ORM'ler (Prisma, Drizzle, Django, TypeORM, golang-migrate) arasında sıfır kesinti deployment'ları için…
Migration
kortix-ai/suna
How to change the database schema in this repo. An agent skill from kortix-ai/suna.
Migrate Create
ruvnet/ruflo
Create a new sequentially numbered database migration with up/down SQL files
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Questions about Migrations
What does Migrations do?
Implementation details for EF Core migrations. An agent skill from dotnet/efcore. Migrations is an agent skill from dotnet/efcore, published by the product's own GitHub organization. Implementation details for EF Core migrations.
When should I use Migrations?
Migrations fits situations like: changing MigrationsSqlGenerator; migration operations; historyRepository; related classes.
How do I install Migrations in Claude Code?
Run `npx skills add dotnet/efcore --skill migrations -a claude-code`. Or copy the skill folder (.agents/skills/migrations in dotnet/efcore) into .claude/skills/migrations in your project. Claude Code loads it when a task matches its description.
How do I install Migrations in Codex?
Run `npx skills add dotnet/efcore --skill migrations -a codex`. Or copy the skill folder (.agents/skills/migrations in dotnet/efcore) into .agents/skills/migrations in your project. Codex loads it when a task matches its description.
Can I use Migrations in Cursor, Gemini CLI or GitHub Copilot?
Cursor, Gemini CLI, GitHub Copilot and OpenCode also load SKILL.md folders. With the skills CLI, run `npx skills add dotnet/efcore --skill migrations -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/migrations, .gemini/skills/migrations, .github/skills/migrations and .opencode/skills/migrations in your project.
What does Migrations need to run?
SKILL.md names no scripts, command-line tools or credentials: Migrations is instructions for the agent only.
Does Migrations access the network?
SKILL.md contains no URLs. Any network use would come from the scripts or tools the agent runs. This is read from the text; nothing was executed.
Is Migrations safe to install?
Our automated static check of SKILL.md found no risky patterns, such as piping downloads into a shell, reading credential files or hidden Unicode. It is not a guarantee. Review the folder before installing.
What licence does Migrations use?
Migrations is published under the MIT licence (the repository's licence). It allows redistribution, so the full SKILL.md is shown on this page.
How many tokens does Migrations use?
About 374 tokens (SKILL.md is roughly 1.5k characters). Agents keep only the skill's name and description in context until a task matches; then they load SKILL.md in full.
What are the alternatives to Migrations?
Skills that share tags, products or a category with Migrations: Safe Database Migration Patterns (affaan-m/ECC, 274k stars), Database Migrations (affaan-m/ECC, 274k stars), Reversible Migration (JuliusBrussee/caveman, 110k stars) and Database Migrations (affaan-m/ECC, 274k stars). The comparison table on this page puts their stars, adoption, token cost, safety result and licence side by side.
Who maintains Migrations?
dotnet (a GitHub organization, an official publisher) maintains it in dotnet/efcore, which has 14,800 GitHub stars. The repository holds 17 skills in this directory. The repository was last updated on October 7, 2026.
Source: dotnet/efcore on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.