The company Toptal runs a wonderful api for composing a .gitignore on the fly.

By composing, I mean you give it a list of components that should be considered, and it generates a .gitignore snippet for each and concatenates them into one.

The api has a web interface at gitignore.io:

gitignore.io web interface

But also an api at https://www.toptal.com/developers/gitignore/api/ that can be interacted with from the command line:

$ curl -s https://www.toptal.com/developers/gitignore/api/
gitignore.io help:
  list    - lists the operating systems, programming languages and IDE input types
  :types: - creates .gitignore files for types of operating systems, programming languages or IDEs

Let’s use the api to create some .gitignore files for a project.

MacOS

If the project will be developed on MacOS, let’s make sure to ignore the annoying files it generates automatically:

$ curl -s https://www.toptal.com/developers/gitignore/api/macos

This returns:

# Created by https://www.toptal.com/developers/gitignore/api/macos
# Edit at https://www.toptal.com/developers/gitignore?templates=macos

### macOS ###
# General
.DS_Store
.AppleDouble
.LSOverride

# Icon must end with two \r
Icon


# Thumbnails
._*

# Files that might appear in the root of a volume
.DocumentRevisions-V100
.fseventsd
.Spotlight-V100
.TemporaryItems
.Trashes
.VolumeIcon.icns
.com.apple.timemachine.donotpresent

# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk

### macOS Patch ###
# iCloud generated files
*.icloud

# End of https://www.toptal.com/developers/gitignore/api/macos

Pretty neat! But you probably won’t just be concerned with ignoring MacOS generated files. Let’s say we are building a website using the static site builder called hugo and we want to include this as well.

MacOS + Hugo

$ curl -s https://www.toptal.com/developers/gitignore/api/macos,hugo

This returns:

# Created by https://www.toptal.com/developers/gitignore/api/macos,hugo
# Edit at https://www.toptal.com/developers/gitignore?templates=macos,hugo

### Hugo ###
# Generated files by hugo
/public/
/resources/_gen/
/assets/jsconfig.json
hugo_stats.json

# Executable may be added to repository
hugo.exe
hugo.darwin
hugo.linux

# Temporary lock file while building
/.hugo_build.lock

### macOS ###
# General
.DS_Store
.AppleDouble
.LSOverride

# Icon must end with two \r
Icon


# Thumbnails
._*

# Files that might appear in the root of a volume
.DocumentRevisions-V100
.fseventsd
.Spotlight-V100
.TemporaryItems
.Trashes
.VolumeIcon.icns
.com.apple.timemachine.donotpresent

# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk

### macOS Patch ###
# iCloud generated files
*.icloud

# End of https://www.toptal.com/developers/gitignore/api/macos,hugo

Notice that the result is the composition of a MacOS snippet and a Hugo snippet! Pretty neat.

Okay, next, let’s say our hugo site will be making use of some Nodejs modules, and include a section for Node.

MacOS + Hugo + Node

$ curl -s https://www.toptal.com/developers/gitignore/api/macos,hugo,node

This returns:

# Created by https://www.toptal.com/developers/gitignore/api/macos,hugo,node
# Edit at https://www.toptal.com/developers/gitignore?templates=macos,hugo,node

### Hugo ###
# Generated files by hugo
/public/
/resources/_gen/
/assets/jsconfig.json
hugo_stats.json

# Executable may be added to repository
hugo.exe
hugo.darwin
hugo.linux

# Temporary lock file while building
/.hugo_build.lock

### macOS ###
# General
.DS_Store
.AppleDouble
.LSOverride

# Icon must end with two \r
Icon


# Thumbnails
._*

# Files that might appear in the root of a volume
.DocumentRevisions-V100
.fseventsd
.Spotlight-V100
.TemporaryItems
.Trashes
.VolumeIcon.icns
.com.apple.timemachine.donotpresent

# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk

### macOS Patch ###
# iCloud generated files
*.icloud

### Node ###
# Logs
logs
*.log
npm-debug.log*
yarn-debug.log*
yarn-error.log*
lerna-debug.log*
.pnpm-debug.log*

# Diagnostic reports (https://nodejs.org/api/report.html)
report.[0-9]*.[0-9]*.[0-9]*.[0-9]*.json

# Runtime data
pids
*.pid
*.seed
*.pid.lock

# Directory for instrumented libs generated by jscoverage/JSCover
lib-cov

# Coverage directory used by tools like istanbul
coverage
*.lcov

# nyc test coverage
.nyc_output

# Grunt intermediate storage (https://gruntjs.com/creating-plugins#storing-task-files)
.grunt

# Bower dependency directory (https://bower.io/)
bower_components

# node-waf configuration
.lock-wscript

# Compiled binary addons (https://nodejs.org/api/addons.html)
build/Release

# Dependency directories
node_modules/
jspm_packages/

# Snowpack dependency directory (https://snowpack.dev/)
web_modules/

# TypeScript cache
*.tsbuildinfo

# Optional npm cache directory
.npm

# Optional eslint cache
.eslintcache

# Optional stylelint cache
.stylelintcache

# Microbundle cache
.rpt2_cache/
.rts2_cache_cjs/
.rts2_cache_es/
.rts2_cache_umd/

# Optional REPL history
.node_repl_history

# Output of 'npm pack'
*.tgz

# Yarn Integrity file
.yarn-integrity

# dotenv environment variable files
.env
.env.development.local
.env.test.local
.env.production.local
.env.local

# parcel-bundler cache (https://parceljs.org/)
.cache
.parcel-cache

# Next.js build output
.next
out

# Nuxt.js build / generate output
.nuxt
dist

# Gatsby files
.cache/
# Comment in the public line in if your project uses Gatsby and not Next.js
# https://nextjs.org/blog/next-9-1#public-directory-support
# public

# vuepress build output
.vuepress/dist

# vuepress v2.x temp and cache directory
.temp

# Docusaurus cache and generated files
.docusaurus

# Serverless directories
.serverless/

# FuseBox cache
.fusebox/

# DynamoDB Local files
.dynamodb/

# TernJS port file
.tern-port

# Stores VSCode versions used for testing VSCode extensions
.vscode-test

# yarn v2
.yarn/cache
.yarn/unplugged
.yarn/build-state.yml
.yarn/install-state.gz
.pnp.*

### Node Patch ###
# Serverless Webpack directories
.webpack/

# Optional stylelint cache

# SvelteKit build / generate output
.svelte-kit

# End of https://www.toptal.com/developers/gitignore/api/macos,hugo,node

A file with a section for MacOS, Hugo, and Node!

Oh, let’s add Go, too, since it’s possible to add go modules to a Hugo site:

MacOS + Hugo + Node + Go

# Created by https://www.toptal.com/developers/gitignore/api/macos,hugo,go
# Edit at https://www.toptal.com/developers/gitignore?templates=macos,hugo,go

### Go ###
# If you prefer the allow list template instead of the deny list, see community template:
# https://github.com/github/gitignore/blob/main/community/Golang/Go.AllowList.gitignore
#
# Binaries for programs and plugins
*.exe
*.exe~
*.dll
*.so
*.dylib

# Test binary, built with `go test -c`
*.test

# Output of the go coverage tool, specifically when used with LiteIDE
*.out

# Dependency directories (remove the comment below to include it)
# vendor/

# Go workspace file
go.work

### Hugo ###
# Generated files by hugo
/public/
/resources/_gen/
/assets/jsconfig.json
hugo_stats.json

# Executable may be added to repository
hugo.exe
hugo.darwin
hugo.linux

# Temporary lock file while building
/.hugo_build.lock

### macOS ###
# General
.DS_Store
.AppleDouble
.LSOverride

# Icon must end with two \r
Icon


# Thumbnails
._*

# Files that might appear in the root of a volume
.DocumentRevisions-V100
.fseventsd
.Spotlight-V100
.TemporaryItems
.Trashes
.VolumeIcon.icns
.com.apple.timemachine.donotpresent

# Directories potentially created on remote AFP share
.AppleDB
.AppleDesktop
Network Trash Folder
Temporary Items
.apdisk

### macOS Patch ###
# iCloud generated files
*.icloud

# End of https://www.toptal.com/developers/gitignore/api/macos,hugo,go

That’s our completed file for an example project being programmed on a MacOS and using Hugo, Node, and Go!

Extras

Use gitignore.io domain instead

The domain https://gitignore.io runs a redirect service to https://toptal.com/developers/gitignore so the api can be accessed in a more memorable way. Just add –location/-L to the curl command to follow redirects.

$ curl -sI https://gitignore.io/api/
HTTP/2 301
date: Fri, 17 May 2024 19:16:12 GMT
content-type: text/html
content-length: 167
location: https://www.toptal.com/developers/gitignore/api/
cache-control: max-age=3600
expires: Fri, 17 May 2024 20:16:12 GMT
server: cloudflare

So, for instance, a Python .gitignore can be generated by running:

$ curl -sL https://gitignore.io/api/python

Shell function / Git alias

Finally, as another extra the api can be added as a shell function or git alias, as described in their documentation.

Let’s add a git alias:

$ git config --global alias.ignore \
'!gi() { curl -sL https://gitignore.io/api/$@ ;}; gi'

And use it to generate a Rust .gitignore:

$ git ignore rust,macos

Pretty slick, right!?