DiffHub

Review your git branch in a cmux browser split, with inline comments you can hand to an agent

Run one command inside any git repository and DiffHub serves a GitHub-style diff of your branch at localhost:2047.

Demo

Browse any public GitHub pull request in the hosted viewer, with nothing installed.

Install

npm install -g diffhub

Or run it without installing: npx diffhub@latest.

Quickstart

Run inside any git repository.

# Review the current branch in a cmux browser split
diffhub cmux

# The same viewer in your default browser
diffhub

# Compare against a different base branch
diffhub cmux --base develop

# Review a repository in another directory
diffhub cmux --repo ~/Code/mblode/cmux

DiffHub diffs your branch against the merge-base with the detected base branch, preferring origin/main so unpushed commits still show up. It watches the repository and refreshes as you work.

Commands

Command	Description
diffhub	Open DiffHub in your default browser
diffhub cmux	Open DiffHub in a cmux browser split
diffhub serve	Same as diffhub, starts the local web app

Options

diffhub and diffhub serve

Flag	Default	Description
-p, --port <port>	2047	Port to serve on
-r, --repo <path>	cwd	Path to the git repository
-b, --base <branch>	auto	Base branch to diff against
--no-open		Skip automatic browser open

diffhub cmux

Flag	Default	Description
-r, --repo <path>	cwd	Path to the git repository
-b, --base <branch>	auto	Base branch to diff against

Keyboard shortcuts

Key	Action
j / k	Next / previous file
s	Toggle split / stacked view
c	Collapse or expand the whole file
/	Focus the file filter
r	Refresh the diff

Notes

• Node.js 20.11+ or Bun 1.0.23+, and a git repository with at least one commit on the current branch.
• cmux mode expects cmux.app installed on macOS at /Applications/cmux.app.
• Comments live in .git/diffhub-comments.json in the repository you are reviewing, and copy out as a markdown review prompt for a coding agent.

License

MIT

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Crafted by Matthew Blode