Git Initial Setup

Git Initial Setup for Main Protection

Standardize main-branch protection for repositories created by git init/clone. Combine GitHub branch protection (Option A) with global hook defaults and local pre-commit/pre-push hooks (Option B) for defense in depth. Absorb cross-platform environment differences with .gitattributes and .editorconfig.

When to Use This Skill

Use this skill when:

• Defining default protections for new repos created by git init/clone
• Rolling out global hook defaults across developer machines
• Enforcing Pull Request (PR)-only merges for main in team repositories
• Preventing accidental commits/pushes during release preparation
• Absorbing cross-platform line-ending and encoding differences in team repositories
• Adding local safeguards for private repos without protection rules
• Auditing protection coverage before a major release

Related Skills

• git-commit-practices - Commit workflow and conventions
• github-pr-workflow - PR creation and merge flow
• skills-author-skill - Skill documentation standards
• skills-validate-skill - Validate skill quality

Dependencies

• Git 2.30+ (required)
• Bash or PowerShell (for hook scripts)
• GitHub account with repo admin access (for branch protection rules)

Core Principles

1. Defense in Depth - Combine server-side and local protections (基礎と型)
2. Least Privilege - Minimize who can push to main
3. Clear Workflow - Make PR-only flow explicit (成長の複利)
4. Transparent Exceptions - Document emergency paths (ニュートラル)
5. Automation First - Reduce human error with repeatable scripts (継続は力)

Workflow: Protect Main Branch

Step 1: Set Branch Protection Rule

Create a minimal branch protection rule for main that requires pull requests. This is the foundation — without it, anyone can push directly to main.

Settings > Branches > Add rule
Branch name pattern: main
Enable: Require a pull request before merging

Use when setting up any new repository or adding protection to an existing one.

Values: 基礎と型 / 継続は力

Step 2: Generate Repository Environment Files

Add .gitattributes and .editorconfig to absorb cross-platform differences. Without these files, team members on different OSes or AI agent sandboxes may see all files as modified after clone.

.gitattributes (line-ending normalization):

* text=auto eol=lf
*.ps1 text eol=crlf
*.bat text eol=crlf
*.cmd text eol=crlf
*.sln text eol=crlf
*.png binary
*.jpg binary
*.ico binary

.editorconfig (editor settings normalization):

root = true

[*]
charset = utf-8
end_of_line = lf
indent_style = space
indent_size = 4
insert_final_newline = true
trim_trailing_whitespace = true

[*.{yml,yaml}]
indent_size = 2

[*.md]
trim_trailing_whitespace = false

[Makefile]
indent_style = tab

For existing repositories, run git add --renormalize . after adding .gitattributes to re-normalize tracked files.

Use when creating a new repository or onboarding team members with different OSes, editors, or AI agents.

Values: 基礎と型 / 余白の設計

Step 3: Configure Review Requirements

Define review requirements so main merges are intentional and traceable. Enable Code Owners and dismiss stale approvals on new commits to maintain accountability.

Require a pull request before merging:
  ✅ Require approvals: 1
  ✅ Dismiss stale pull request approvals when new commits are pushed
  ✅ Require review from Code Owners

Use when you need accountability for every main merge and consistent review quality.

Values: 成長の複利 / ニュートラル

Step 4: Require Status Checks

Gate merges on CI checks so broken builds never land in main. Required checks keep main green and reduce rollback risk.

required_status_checks:
  - ci/build
  - ci/test

Use when your repository has CI pipelines and you want to prevent regressions.

Values: 継続は力 / 基礎と型

Step 5: Restrict Push Access

Limit direct push access and ensure protections apply to administrators. Enable "Include administrators" and restrict who can push to matching branches.

✅ Include administrators
✅ Restrict who can push to matching branches
   Allowed: release-bot only

Use in regulated or audited environments where strong guarantees are needed.

Values: ニュートラル / 基礎と型

Step 6: Install Local Hooks

Install local pre-commit and pre-push hooks to block commits and pushes to main before changes reach the remote.

# Install hooks for this repo
./scripts/setup.sh

Use for private repos without branch protection rules, as a local safety net, or during release windows.

Note: As an alternative to copying hooks into .git/hooks/, you can use a repository-level hooks directory with git config core.hooksPath .githooks. This keeps hooks version-controlled and automatically applied after clone — no setup script required.

Troubleshooting (Windows): If setup.ps1 fails with a security error, your PowerShell execution policy may be set to Restricted. Run Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy RemoteSigned to allow local scripts, then retry.

Values: 継続は力 / 基礎と型

Step 7: Set Global Hook Defaults

Configure global hook defaults so new repositories inherit protections automatically via core.hooksPath.

git config --global core.hooksPath "~/.githooks"

Use when you manage multiple repositories on the same workstation and want automatic protection.

Values: 基礎と型 / 継続は力

Step 8: Roll Out to Team

Roll out protections with clear communication: announce the PR-only policy, share setup scripts, and update onboarding docs.

## Onboarding Checklist
- [ ] Run `./scripts/setup.sh` to install hooks
- [ ] Confirm branch protection is enabled on main
- [ ] Review PR workflow in github-pr-workflow

Use when you manage multiple repositories or need consistent protections across teams.

Values: 成長の複利 / 継続は力

Step 9: Handle Emergencies

Handle common failures without disabling protections permanently. For emergency hotfixes, use a documented admin bypass with post-incident review.

# Emergency hotfix: bypass hook with explicit approval only
git push --no-verify origin hotfix/critical-fix
# Post-incident: review and document the bypass

Use when protections block an urgent fix or hook behavior differs across environments.

Values: ニュートラル / 温故知新

Best Practices

• Add .gitattributes and .editorconfig at repository creation time
• Set global hook defaults before creating new repos
• Use Pull Request (PR) reviews for all main merges
• Set branch protection after the remote exists
• Require at least one approval for main merges
• Keep a written record of protection settings
• Review protections after org or team changes
• Document emergency bypass steps in a runbook

Use core.hooksPath for all repos.
Set init.templateDir for new repos.
Avoid direct pushes to main.

Common Pitfalls

• Forgetting to include administrators in protection rules
• Allowing direct pushes for convenience and never removing it
• Relying only on local hooks for team-wide enforcement

Fix: Enable "Include administrators" and document who can push.
Fix: Remove direct push permissions from main once PR flow is stable.
Fix: Add GitHub branch protection to enforce team-wide rules.

Anti-Patterns

• Assuming all team members use the same OS and editor settings (Implicit Environment Assumption)
• Disabling branch protection to make a quick change
• Using --no-verify as a default workflow
• Allowing unrestricted direct pushes to main

FAQ

Q: Can I protect private repositories on the free plan?
A: GitHub branch protection for private repos requires a paid plan. Use local hooks as a fallback.

Q: Will the PowerShell hook run automatically on Windows?
A: Git for Windows runs hooks via Bash by default. Use the Bash hook or copy it into a shared hook path.

Q: Does git init automatically install these hooks?
A: Only if you set core.hooksPath or init.templateDir globally. Otherwise, hooks are not installed by default.

Q: Does this block admins?
A: Only if "Include administrators" is enabled in the branch protection rule.

Quick Reference

Step Summary

Decision Table

# Install hooks (pre-commit + pre-push) (macOS/Linux/Git Bash)
./scripts/setup.sh

# Install hooks (PowerShell)
.\scripts\setup.ps1

# Set global hooks path (all repos)
git config --global core.hooksPath "~/.githooks"

# Set init template (new repos only)
git config --global init.templateDir "~/.git-template"

# Verify current branch
git branch --show-current

Resources

• GitHub Protected Branches
• Git Hooks Documentation