// Generates git patch files from codebase modifications for local application. Use when user mentions patch, diff, export changes, bring changes back, apply locally, or after editing uploaded codebases.
| name | generating-patches |
| description | Generates git patch files from codebase modifications for local application. Use when user mentions patch, diff, export changes, bring changes back, apply locally, or after editing uploaded codebases. |
Generate portable git patch files from codebase modifications, enabling users to apply Claude's edits to their local repositories.
Activate after modifying files in an uploaded codebase when the user needs to transfer changes back to their local environment. Typical workflow: user uploads zip → Claude edits files → this skill exports changes as a patch.
Verify git is available and the working directory is a git repository (or can be initialized as one):
git status 2>/dev/null || git init
If working with an uploaded codebase that lacks git history, initialize and create a baseline commit before making edits:
git init
git add -A
git commit -m "Baseline: original uploaded state"
After completing edits, generate a unified diff:
# For uncommitted changes (working tree modifications)
git diff > /mnt/user-data/outputs/changes.patch
# If changes are staged but not committed
git diff --cached > /mnt/user-data/outputs/changes.patch
# For both staged and unstaged
git diff HEAD > /mnt/user-data/outputs/changes.patch
For committed changes (preserves commit messages and metadata):
# All commits since baseline
git format-patch --stdout baseline..HEAD > /mnt/user-data/outputs/changes.patch
# Or specify number of commits
git format-patch --stdout -n 3 > /mnt/user-data/outputs/changes.patch
Binary files: Git diff excludes binaries by default. Warn the user if binary files were modified:
git diff --name-only --diff-filter=M | xargs file | grep -v "ASCII\|UTF-8\|empty"
Large patches: For extensive changes, consider splitting by directory or file type:
git diff -- "*.py" > /mnt/user-data/outputs/python-changes.patch
git diff -- src/ > /mnt/user-data/outputs/src-changes.patch
No changes detected: Verify files were actually modified. Common issues:
git add first)Always output to /mnt/user-data/outputs/ with a descriptive filename. Provide the download link:
[Download changes.patch](computer:///mnt/user-data/outputs/changes.patch)
Include these instructions with every patch delivery:
To apply this patch locally:
cd /path/to/your/repo
# Preview changes (dry run)
git apply --check changes.patch
# Apply to working tree
git apply changes.patch
If using format-patch output (includes commit metadata):
git am changes.patch
Troubleshooting:
git apply --reject changes.patch — applies what it can, writes .rej files for conflictsgit apply -R changes.patch — reverses a previously applied patchgit apply --3way changes.patch — enables three-way merge for conflictsWhen requested, generate a pull request description from the patch:
# Extract summary of changes
echo "## Summary"
git diff --stat
echo ""
echo "## Changes"
git diff --name-only | while read f; do echo "- \`$f\`"; done
Combine with a brief description of what was changed and why, suitable for GitHub PR body.
Generate navigable code maps for unfamiliar codebases. Use when exploring a new codebase, needing to understand project structure, or before diving into code modifications. Extracts exports/imports via AST (tree-sitter) to create _MAP.md files per directory. Triggers on "map this codebase", "understand this project structure", "generate code map", or when starting work on an unfamiliar repository.
REQUIRED for all skill development. Automatically version control every skill file modification for rollback/comparison. Use after init_skill.sh, after every str_replace/create_file, and before packaging.