🕰️ dtm

Dotfile Time Machine. Automatically snapshots your config files and pushes them to a private GitHub repo on a schedule.

DTM came from the frustration of tweaking dotfiles or config files, accidentally breaking things weeks later, and having no idea what changed. The goal was to create something simple that quietly backs up your files to GitHub on a schedule, makes it easy to track changes over time, and lets you roll back any file to a previous version whenever needed.

Install

npm install -g @ariian/dtm

Setup

dtm init

You'll be prompted for:

? GitHub repo URL (SSH or HTTPS): [email protected]:you/dotfiles-backup.git
? How often should snapshots run? Once a day
? Auto-push to GitHub after every snapshot? Yes
? Select dotfiles to track: ~/.zshrc, ~/.gitconfig

Create a private GitHub repo before running dtm init.

GitHub Connection

SSH (recommended)

Use an SSH URL when prompted:

[email protected]:you/dotfiles-backup.git

Make sure your SSH key is added to your macOS Keychain so pushes work silently in the background:

ssh-add --apple-use-keychain ~/.ssh/id_ed25519

Test it:

ssh -T [email protected]
# Hi you! You've successfully authenticated.

HTTPS

Use an HTTPS URL when prompted:

https://github.com/you/dotfiles-backup.git

Store your GitHub Personal Access Token in macOS Keychain:

git config --global credential.helper osxkeychain

How it works

1. you run       →  dtm snapshot
2. dtm copies    →  your tracked dotfiles into ~/.dtm/
3. dtm commits   →  git commit -m "snapshot 2026-05-23 22:00:00"
4. dtm pushes    →  git push origin main
5. done          →  ✔ snapshot saved and pushed to GitHub

On a schedule, this runs automatically via macOS launchd.

Upgrading from v1.1.x

v1.2.0 changed how files are stored inside ~/.dtm/ — nested files now mirror their original directory structure (e.g. ~/.ssh/config is stored as .ssh/config instead of just config). Root-level dotfiles like .zshrc and .gitconfig are unaffected.

If you tracked any nested files, run once after upgrading:

dtm migrate

This moves your stored files to the new structure, updates your config, and commits the change — no data is lost.

Commands

Setup

dtm init                        # first time setup wizard
dtm status                      # show tracked files, last snapshot, schedule

Snapshots

dtm snapshot                    # take a snapshot now
dtm log                         # show full snapshot history

File Tracking

dtm watch ~/.npmrc              # start tracking a new file
dtm watch ~/Library/Application\ Support/Code/User/settings.json
dtm unwatch ~/.vimrc            # stop tracking a file

Add any file to your snapshot with dtm watch <path>.

Diffing

dtm diff                        # what changed since last snapshot
dtm diff .zshrc                 # what changed in one specific file
dtm diff .ssh/config            # nested files use the relative path

Restoring

dtm restore .zshrc              # restore .zshrc to 1 snapshot ago (default)
dtm restore .zshrc -n 5        # restore .zshrc to 5 snapshots ago
dtm restore .ssh/config -n 2   # nested files use the relative path

Scheduling

dtm schedule                    # enable automatic snapshots via launchd
dtm schedule --off              # disable automatic snapshots

Scheduling is enabled automatically during dtm init. You can disable or re-enable it anytime with the commands above.

Reset

dtm reset                       # remove all dtm data and config

Migration

dtm migrate                     # migrate stored files to the new path structure (v1.2.0+)

Node flags

dtm --version                   # print version number
dtm --help                      # show all commands

File locations

~/.dtm/                         # git snapshot repo
~/.config/dtm/config.json       # dtm config file
~/Library/LaunchAgents/
  com.dtm.snapshot.plist        # launchd scheduler (after dtm schedule)

License

MIT © Arian Najafi Yamchelo — arii.dev