How to Create a .gitignore File (2026)
A .gitignore file is one of the first things you should create in any new repository. Without it, Git tracks everything — node_modules, compiled binaries, .env secrets, IDE configuration, OS junk files, and build artifacts. Your repository bloats, secrets leak, and collaborators deal with merge conflicts in files they never touch.
- Covers pattern syntax.
- Covers language-specific ignore rules.
- Covers common .gitignore mistakes.
- Covers global .gitignore for your machine.
Pattern Syntax
Glob patterns: * matches any characters within a filename (*.log ignores all log files). ** matches across directories (**/test ignores test directories at any depth). ? matches a single character.
Directory trailing slash: build/ ignores the entire build directory and everything in it. Without the slash, build would match both files and directories named build.
Negation: ! re-includes a previously ignored pattern. If you ignore *.log but want to keep important.log, add !important.log after the *.log rule. Order matters — negation must come after the ignore rule.
Language-Specific Ignore Rules
Node.js: always ignore node_modules/ (it can contain 100,000+ files), dist/ and build/ (compiled output), .env (secrets), *.log, and coverage/ (test coverage reports). node_modules alone can be hundreds of megabytes.
-webkit-backdrop-filter alongside backdrop-filter for Safari support. Without the prefix, the effect is invisible to roughly 25% of mobile users.Python: ignore __pycache__/, *.pyc, *.pyo (compiled bytecode), venv/ or env/ (virtual environments), .egg-info/, dist/, build/, and .pytest_cache/. Virtual environments should be recreated from requirements.txt, never committed.
React: in addition to Node.js patterns, ignore .env.local, .env.development.local, .env.test.local, and .env.production.local. Create React App generates these environment-specific files locally.
Common .gitignore Mistakes
Adding .gitignore too late: if files are already tracked by Git, adding them to .gitignore does not untrack them. You need to run git rm --cached filename to remove them from tracking first.
backdrop-filter inside a position: fixed element can cause severe scroll performance issues. Test thoroughly on real iOS devices.Ignoring too much: if your .gitignore is overly aggressive, important files might be missing from the repository. After creating .gitignore, verify with git status that the right files are being tracked.
Not ignoring enough: IDE settings (.idea/, .vscode/), OS files (.DS_Store, Thumbs.db), and editor swap files (*.swp, *~) should always be ignored. These are machine-specific and cause unnecessary conflicts.
Global .gitignore for Your Machine
Your personal machine generates files that should never be in any repository: .DS_Store (macOS), Thumbs.db (Windows), .idea/ (JetBrains IDEs), .vscode/ (VS Code). Rather than adding these to every project, create a global .gitignore.
Set it up with git config --global core.excludesfile ~/.gitignore_global. Then add OS and IDE patterns to that file. This keeps project .gitignore files focused on project-specific patterns.
Global gitignore handles your environment. Project gitignore handles the project. This separation means team members using different OSes and editors do not need to coordinate their ignore rules.