macOSDefaultApps

View and set default apps on macOS — which app opens which file extension, UTI or URL scheme.

Install with Homebrew

brew tap klabast/tap
brew trust klabast/tap                  # required for third-party taps
brew install mda                        # cli
brew install --cask macosdefaultapps    # app

Lineage

A modern successor to RCDefaultApp, SwiftDefaultApps and duti that allows you to set the default app on modern macOS.

What it does

App and CLI over the same core — point and click, or script it.
Covers every type and URL scheme your installed apps declare.
Reads and writes duti-syntax settings files, so what you already have keeps working.
English, Deutsch, Français, Español, Italiano, Português, Nederlands, Polski, 简体中文.

CLI

mda get md                          # default handler for .md
mda ls md                           # all candidates, default marked *
mda set com.sublimetext.4 md        # set a handler
mda dump --json                     # every curated type + current handler
mda apply ~/.duti                   # apply a settings file

Dotfiles

Your associations are a plain text file. Snapshot them, put ~/.mda in your dotfiles, restore on the next machine — apps that aren't installed yet are skipped and reported, run it again after installing them.

mda save                    # snapshot current handlers to ~/.mda/default
git init ~/.mda             # make saves diffable (mda warns if you don't)
mda apply                   # restore — on this or any other machine

Requires macOS 15+. Changing the default browser always shows a macOS consent dialog — that's the system, not the app.