Welcome to Infat

Infat is an ultra-powerful, macOS-native CLI tool for declaritively managing both file-type and URL-scheme associations. Avoid the hassle of navigating sub-menus to setup your default browser or image viewer, and the pain of doing that every time you get a new machine. Setup the rules once, and bask in your own ingenuity forevermore. Take back control, and bind your openers to whatever. You. Want. Override everything! Who's going to stop you?

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Summary

• List which apps open for a given file extension or URL scheme (Like when you double click a file in Finder)
• Set a default application for a file extension or URL scheme
• Load associations from a TOML config ([extensions] [types] and [schemes] tables)
• Verbose, scriptable, and ideal for power users and admins

Get Started

Get started by installing Infat — jump to the Install section below.

Tutorial

1. Getting assocation information

# Show the default app for .txt files and all registered apps
infat info --ext txt

2. Setting a Default Application

Tip

These aren't strict extensions, for example, yml and yaml extensions share a common resolver.

# Use TextEdit for .md files
infat set TextEdit --ext md

# Use VSCode for .json files
infat set VSCode --ext json

3. Binding a URL Scheme

# Use Mail.app for mailto: links
infat set Mail --scheme mailto

4. Fallback types

Tip

Openers are cascading in macOS. Most common file formats will have their own identifier, Which will be read from before the plain-text type it inherits from Try setting from extension if you face unexpected issues

# Set VSCode as the opener for files containing text
infat set VSCode --type plain-text

Infat currently supports these supertypes:

• plain-text
• text
• csv
• image
• raw-image
• audio
• video
• movie
• mp4-audio
• quicktime
• mp4-movie
• archive
• sourcecode
• c-source
• cpp-source
• objc-source
• shell
• makefile
• data
• directory
• folder
• symlink
• executable
• unix-executable
• app-bundle

5. Configuration

Place a TOML file at $XDG_CONFIG_HOME/infat/config.toml (or pass --config path/to/config.toml).

Note

$XDG_CONFIG_HOME is not set by default, you need to set in your shell config ex: .zshenv.

On the right is the app you want to bind. You can pass:

1. The name (As seen when you hover on the icon) IF It's in a default location.
2. The relative path (To your user directory: ~)
3. The absolute path

All case sensitive, all can be with or without a .app suffix, and no shell expansions...

[extensions]
md    = "TextEdit"
html  = "Safari"
pdf   = "Preview"

[schemes]
mailto = "Mail"
web    = "Safari"

[types]
plain-text = "VSCode"

Run without arguments to apply all entries.

infat --config ~/.config/infat/config.toml

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Design Philosophy

• Minimal & Scriptable
  Infat is a single-binary tool that plays well in shells and automation pipelines.

• macOS-First
  Leverages native NSWorkspace, Launch Services, and UTType for robust integration.

• Declarative Configuration
  TOML support allows you to version-control your associations alongside other dotfiles.

Building and Debugging

You’ll need just and Swift 5.9+:

# Debug build
just build

# Release build
just build-release

# Run in debug mode
just run "list txt"

# Enable verbose logging for troubleshooting
infat --verbose info --ext pdf

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Install

Homebrew

brew update # Optional but recommended
brew install infat

From Source

Please make sure just (our command-runner) is installed before running. If you don't want to use just, the project is managed with SPM, and you can build with "Swift build -c release" and move the result in the .build folder to wherever.

git clone https://github.com/philocalyst/infat.git && cd infat
just package && mv dist/infat* /usr/local/bin/infat # Wildcard because output name includes platform

Changelog

For the full history of changes, see CHANGELOG.md.

Libraries Used

• ArgumentParser
• swift-log
• PListKit
• swift-toml

Acknowledgements

• Inspired by duti
• Built with Swift, thanks to corporate overlord Apple’s frameworks
• Thanks to all contributors and issue submitters (One day!!)

License

Infat is licensed under the MIT License.
Feel free to use, modify, and distribute!