Structures git workflow practices. Use when making any code change. Use when committing, branching, resolving conflicts, splitting uncommitted work in a messy working tree into clean atomic commits, opening or reviewing a pull request (PR), pushing to a remote, or when you need to organize work acro

Git Workflow and Versioning Overview Git is your safety net. Treat commits as save points, branches as sandboxes, and history as documentation. With AI agents generating code at high speed, disciplined version control is the mechanism that keeps changes manageable, reviewable, and reversible. When to Use Always. Every code change flows through git. Core Principles Trunk Based Development (Recommended) Keep main always deployable. Work in short lived feature branches that merge back within 1 3 days. Long lived development branches are hidden costs — they diverge, create merge conflicts, and delay integration. DORA research consistently shows trunk based development correlates with high performing engineering teams. This is the recommended default. Teams using gitflow or long lived branches can adapt the principles (atomic commits, small changes, descriptive messages) to their branching model — the commit discipline matters more than the specific branching strategy. Dev branches are costs. Every day a branch lives, it accumulates merge risk. Release branches are acceptable. When you need to stabilize a release while main moves forward. Feature flags long branches. Prefer deploying incomplete work behind flags rather than keeping it on a branch for weeks. 1. Commit Early, Commit Often Each successful increment gets its own commit. Don't accumulate large uncommitted changes. Commits are save points. If the next change breaks something, you can revert to the last known good state instantly. 2. Atomic Commits Each commit does one logical thing: 3. Descriptive Messages Commit messages explain the why , not just the what : Format: Types: feat — New feature fix — Bug fix refactor — Code change that neither fixes a bug nor adds a feature test — Adding or updating tests docs — Documentation only chore — Tooling, dependencies, config 4. Keep Concerns Separate Don't combine formatting changes with behavior changes. Don't combine refactors with features. Each type of change should be a separate commit — and ideally a separate PR: Separate refactoring from feature work. A refactoring change and a feature change are two different changes — submit them separately. This makes each change easier to review, revert, and understand in history. Small cleanups (renaming a variable) can be included in a feature commit at reviewer discretion. 5. Size Your Changes Target ~100 lines per commit/PR. Changes over ~1000 lines should be split. See the splitting strategies in code review and quality for how to break down large changes. Branching Strategy Feature Branches Branch from main (or the team's default branch) Keep branches short lived (merge within 1 3 days) — long lived branches are hidden costs Delete branches after merge Prefer feature flags over long lived branches for incomplete features Branch Naming Working with Worktrees For parallel AI agent work, use git worktrees to run multiple branches simultaneously: Benefits: Multiple agents can work on different features simultaneously No branch switching needed (each directory has its own branch) If one experiment fails, delete the worktree — nothing is lost Changes are isolated until explicitly merged The Save Point Pattern This pattern means you never lose more than one increment of work. If an agent goes off the rails, git reset hard HEAD takes you back to the last successful state. Change Summaries After any modification, provide a structured summary. This makes review easier, documents scope discipline, and surfaces unintended changes: This pattern catches wrong assumptions early and gives reviewers a clear map of the change. The "DIDN'T TOUCH" section is especially important — it shows you exercised scope discipline and didn't go on an unsolicited renovation. Pre Commit Hygiene Before every commit: Automate this with git hooks: Handling Generated Files Commit generated files only if the project expects them (e.g., package lock.json , Prisma migrations) Don't commit build output ( dist/ , .next/ ), environment files ( .env ), or IDE config ( .vscode/settings.json unless shared) Have a .gitignore that covers: node modules/ , dist/ , .env , .env.local , .pem Using Git for Debugging Release & Versioning Commits are how you track change; a version is how your consumers track it. The moment anything else depends on your code — another team, a published package, a deployed client — "latest on main" stops being a sufficient answer to "what am I running, and is it safe to upgrade?" A version number and a changelog are the contract that answers it. Semantic Versioning For anything with consumers, version MAJOR.MINOR.PATCH and let the number carry meaning: The number is a promise, so make the code match it. A "patch" that changes behavior consumers relied on is a major change wearing a disguise (Hyrum's Law — see the api and interface design skill). When unsure whether a change is breaking, assume it is; a surprise major is far cheaper than a broken consumer. Tag the release, and let the tag be the source of truth A release is an immutable point in history, not a moving branch. Tag it so it can always be reproduced: Derive the version from the tag rather than hand editing it in scattered files, so the artifact, the tag, and the changelog can never disagree. Keep a changelog written for humans A changelog is not git log . It's the curated, consumer facing answer to "what changed and do I care?" — grouped by Added / Changed / Fixed / Deprecated / Removed / Security , newest on top, every entry phrased around user impact, not internal mechanics. Write the entry in the same change that makes the change, while the impact is fresh — not reconstructed from commit archaeology at release time. Breaking changes get a migration note and a deprecation window (follow the deprecation and migration skill); shipping the actual release is the shipping and launch skill's job — this section is the versioning contract that feeds it. Common Rationalizations Rationalization Reality "I'll commit when the feature is done" One giant commit is impossible to review, debug, or revert. Commit each slice. "The message doesn't matter" Messages are documentation. Future you (and future agents) will need to understand what changed and why. "I'll squash it all later" Squashing destroys the development narrative. Prefer clean incremental commits from the start. "Branches add overhead" Short lived branches are free and prevent conflicting work from colliding. Long lived branches are the problem — merge within 1 3 days. "I'll split this change later" Large changes are harder to review, riskier to deploy, and harder to revert. Split before submitting, not after. "I don't need a .gitignore" Until .env with production secrets gets committed. Set it up immediately. "It's just a small fix, bump the patch" Check what consumers can observe. A behavior change they relied on is a major, whatever the diff size. "The changelog is just the commit log" Commits are for you; the changelog is for consumers, curated by impact. Generating one from raw commits buries what matters. "We'll write the changelog at release time" By then the impact is reconstructed from memory and half of it is missing. Write the entry with the change. Red Flags Large uncommitted changes accumulating Commit messages like "fix", "update", "misc" Formatting changes mixed with behavior changes No .gitignore in the project Committing node modules/ , .env , or build artifacts Long lived branches that diverge significantly from main Force pushing to shared branches A breaking change shipped under a minor or patch version bump A release with no tag, or a version number hand edited out of sync with the tag A user facing release with no changelog entry, or a changelog that's just dumped commit messages Verification For every commit: [ ] Commit does one logical thing [ ] Message explains the why, follows type conventions [ ] Tests pass before committing [ ] No secrets in the diff [ ] No formatting only changes mixed with behavior changes [ ] .gitignore covers standard exclusions For every release (anything with consumers): [ ] The version bump matches the change: breaking → major, additive → minor, fix → patch [ ] The release is tagged, and the version is derived from the tag, not hand edited out of sync [ ] The changelog has a curated, human readable entry grouped by impact for this version

git-workflow-and-versioning