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…
How to make fallout-migrate handle a new rename, removal, or rewrite by extending an existing IMigrationStep, and when a genuinely new step is warranted.
Custom licenceAuto-check passed
Install Adding A Migration Step
$ npx skills add Fallout-build/Fallout --skill adding-a-migration-step -a claude-codeProject install by default; add -g for ~/.claude/skills/.
$ gh skill install Fallout-build/Fallout adding-a-migration-step --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/Fallout-build/Fallout.git skills-src && mkdir -p .claude/skills && cp -r skills-src/.agents/skills/adding-a-migration-step .claude/skills/adding-a-migration-step && 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 "adding-a-migration-step" agent skill from https://github.com/Fallout-build/Fallout/tree/develop/.agents/skills/adding-a-migration-step into .claude/skills/adding-a-migration-step/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "adding-a-migration-step", 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/Fallout-build/Fallout/tree/develop/.agents/skills/adding-a-migration-stepType 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 Fallout-build/Fallout --skill adding-a-migration-step -a codexProject install goes to .agents/skills/; add -g for ~/.codex/skills/.
$ gh skill install Fallout-build/Fallout adding-a-migration-step --agent codexProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Fallout-build/Fallout.git skills-src && mkdir -p .agents/skills && cp -r skills-src/.agents/skills/adding-a-migration-step .agents/skills/adding-a-migration-step && rm -rf skills-srcUse ~/.agents/skills/ instead of .agents/skills for a personal install.
Codex skills documentation · loads skills from .agents/skills/
Install the "adding-a-migration-step" agent skill from https://github.com/Fallout-build/Fallout/tree/develop/.agents/skills/adding-a-migration-step into .agents/skills/adding-a-migration-step/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "adding-a-migration-step", 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 Fallout-build/Fallout --skill adding-a-migration-step -a cursorProject install goes to .agents/skills/; add -g for ~/.cursor/skills/.
$ gh skill install Fallout-build/Fallout adding-a-migration-step --agent cursorProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Fallout-build/Fallout.git skills-src && mkdir -p .cursor/skills && cp -r skills-src/.agents/skills/adding-a-migration-step .cursor/skills/adding-a-migration-step && 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 "adding-a-migration-step" agent skill from https://github.com/Fallout-build/Fallout/tree/develop/.agents/skills/adding-a-migration-step into .cursor/skills/adding-a-migration-step/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "adding-a-migration-step", 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/Fallout-build/Fallout.git --path .agents/skills/adding-a-migration-step--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 Fallout-build/Fallout --skill adding-a-migration-step -a gemini-cliProject install goes to .agents/skills/; add -g for ~/.gemini/skills/.
$ gh skill install Fallout-build/Fallout adding-a-migration-step --agent gemini-cliProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Fallout-build/Fallout.git skills-src && mkdir -p .gemini/skills && cp -r skills-src/.agents/skills/adding-a-migration-step .gemini/skills/adding-a-migration-step && 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 "adding-a-migration-step" agent skill from https://github.com/Fallout-build/Fallout/tree/develop/.agents/skills/adding-a-migration-step into .gemini/skills/adding-a-migration-step/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "adding-a-migration-step", 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 Fallout-build/Fallout adding-a-migration-stepInstalls 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 Fallout-build/Fallout --skill adding-a-migration-step -a github-copilotProject install goes to .agents/skills/; add -g for ~/.copilot/skills/.
$ git clone --depth 1 https://github.com/Fallout-build/Fallout.git skills-src && mkdir -p .github/skills && cp -r skills-src/.agents/skills/adding-a-migration-step .github/skills/adding-a-migration-step && 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 "adding-a-migration-step" agent skill from https://github.com/Fallout-build/Fallout/tree/develop/.agents/skills/adding-a-migration-step into .github/skills/adding-a-migration-step/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "adding-a-migration-step", 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 Fallout-build/Fallout --skill adding-a-migration-step -a opencodeOpenCode documents no install command of its own. Project install goes to .agents/skills/; add -g for ~/.config/opencode/skills/.
$ gh skill install Fallout-build/Fallout adding-a-migration-step --agent opencodeProject scope by default (.agents/skills/); add --scope user for a personal install.
$ git clone --depth 1 https://github.com/Fallout-build/Fallout.git skills-src && mkdir -p .opencode/skills && cp -r skills-src/.agents/skills/adding-a-migration-step .opencode/skills/adding-a-migration-step && 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 "adding-a-migration-step" agent skill from https://github.com/Fallout-build/Fallout/tree/develop/.agents/skills/adding-a-migration-step into .opencode/skills/adding-a-migration-step/ in this project. Copy the whole folder (SKILL.md and every file beside it), keep the folder name "adding-a-migration-step", 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
adding-a-migration-step- GitHub stars
- 164
- Token cost
- ~529 tokens
- SKILL.md length
- 269 words
- Files
- 1
- Skills in repo
- 8
- Repo updated
- First seen
- Licence
- Custom licence
At a glance
How to make fallout-migrate handle a new rename, removal, or rewrite by extending an existing IMigrationStep, and when a genuinely new step is warranted.
- Works in 4 steps: Find the step for that file type —… → Add a private static readonly Regex… → Apply it as another statement in the… → …
- Asked to add a rename/rewrite rule to fallout-migrate
- SKILL.md covers Adding a new rename, removal,… and When a new step actually is…
- Instructions only: no scripts, shell commands, URLs or credentials in SKILL.md
What it does
Adding A Migration Step is an agent skill from Fallout-build/Fallout. How to make fallout-migrate handle a new rename, removal, or rewrite by extending an existing IMigrationStep, and when a genuinely new step is warranted. Trigger when asked to add a rename/rewrite rule to fallout-migrate, or to touch src/Fallout.Migrate/Migration.cs or its Steps.
Its SKILL.md is about 530 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: ☢️ Fallout — The C/.NET Build System.
When your agent uses it
- Asked to add a rename/rewrite rule to fallout-migrate
- Touch src/Fallout.Migrate/Migration.cs
Example prompts
- “/adding-a-migration-step”
Workflow steps
4 steps, taken from the first numbered list in SKILL.md.
- Find the step for that file type — RewriteCsprojsStep for *.csproj,
- Add a private static readonly Regex field to that step, with a comment
- Apply it as another statement in the step's Rewrite method, incrementing
- Add cases to that step's spec class in tests/Fallout.Migrate.Specs.
What it can do on your machine
Read from SKILL.md and the folder at commit 8333cc8. 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
Adding A Migration Step loads about 529 tokens when it runs. Until then it costs about 76 tokens; SKILL.md has 269 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
Its licence (Custom licence) doesn't allow us to republish the file, so here is its outline and opening line. It has 269 words (~529 tokens).
“fallout-migrate runs a fixed, ordered list of IMigrationStep implementations, built in src/Fallout.Migrate/Migration.cs. A step is one operation over one set of files, and it owns the rewrite rules for those files. RewriteCsprojsStep holds the rules for *.csproj; RewriteCsFilesStep holds the…”
- name
- adding-a-migration-step
Files
Just SKILL.md in .agents/skills/adding-a-migration-step of Fallout-build/Fallout.
Open the folder on GitHubat commit 8333cc8
Compare with similar skills
Adding A Migration Step 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 |
|---|---|---|---|---|---|---|
| Adding A Migration Step this skillFallout-build/Fallout | 164 | — | ~529 | Automated safety check: Pass | Custom licence | |
| 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 | |
| Error Handlingaffaan-m/ECC | 274k | 1 repos | ~2.7k | Automated safety check: Pass | MIT | |
| Database Migrationsaffaan-m/ECC | 274k | 1 repos | ~2.4k | Automated safety check: Pass | MIT | |
| Safe Database Migration Patternsaffaan-m/ECC | 274k | — | ~3.3k | Automated safety check: Pass | MIT |
Similar skills
Reversible Migration
JuliusBrussee/caveman
Implement reversible compatibility-safe transitions. Use for schema, data, API, protocol, configuration, or dependency migrations requiring rollback and…
Error Handling
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Patterns for robust error handling across TypeScript, Python, and Go.
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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…
Safe Database Migration Patterns
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Rules and examples for safe, reversible schema changes in production: zero-downtime column and index changes, large data backfills and ORM migration workflows.
Migrate Create
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Create a new sequentially numbered database migration with up/down SQL files
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Questions about Adding A Migration Step
What does Adding A Migration Step do?
How to make fallout-migrate handle a new rename, removal, or rewrite by extending an existing IMigrationStep, and when a genuinely new step is warranted. Adding A Migration Step is an agent skill from Fallout-build/Fallout. How to make fallout-migrate handle a new rename, removal, or rewrite by extending an existing IMigrationStep, and when a genuinely new step is warranted.
When should I use Adding A Migration Step?
Adding A Migration Step fits situations like: asked to add a rename/rewrite rule to fallout-migrate; touch src/Fallout.Migrate/Migration.cs.
How do I install Adding A Migration Step in Claude Code?
Run `npx skills add Fallout-build/Fallout --skill adding-a-migration-step -a claude-code`. Or copy the skill folder (.agents/skills/adding-a-migration-step in Fallout-build/Fallout) into .claude/skills/adding-a-migration-step in your project. Claude Code loads it when a task matches its description.
How do I install Adding A Migration Step in Codex?
Run `npx skills add Fallout-build/Fallout --skill adding-a-migration-step -a codex`. Or copy the skill folder (.agents/skills/adding-a-migration-step in Fallout-build/Fallout) into .agents/skills/adding-a-migration-step in your project. Codex loads it when a task matches its description.
Can I use Adding A Migration Step 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 Fallout-build/Fallout --skill adding-a-migration-step -a cursor` (or -a gemini-cli, github-copilot or opencode for the others). To copy it by hand, put the folder in .cursor/skills/adding-a-migration-step, .gemini/skills/adding-a-migration-step, .github/skills/adding-a-migration-step and .opencode/skills/adding-a-migration-step in your project.
What does Adding A Migration Step need to run?
SKILL.md names no scripts, command-line tools or credentials: Adding A Migration Step is instructions for the agent only.
Does Adding A Migration Step 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 Adding A Migration Step 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 Adding A Migration Step use?
Adding A Migration Step has a licence file (the repository's licence) that doesn't match a standard licence. Read it on GitHub before reusing the skill.
How many tokens does Adding A Migration Step use?
About 529 tokens (SKILL.md is roughly 2.1k 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 Adding A Migration Step?
Skills that share tags, products or a category with Adding A Migration Step: Database Migrations (affaan-m/ECC, 274k stars), Reversible Migration (JuliusBrussee/caveman, 110k stars), Error Handling (affaan-m/ECC, 274k 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 Adding A Migration Step?
Fallout-build (a GitHub organization) maintains it in Fallout-build/Fallout, which has 164 GitHub stars. The repository holds 8 skills in this directory. The repository was last updated on October 3, 2026.
Source: Fallout-build/Fallout on GitHub. Facts on this page come from the repository at the commit we read; the author's words are quoted as theirs.