DiffHub

GitHub PR-style diff viewer. Opens in the browser and shows tracked changes relative to your merge-base by default, with a UI toggle for uncommitted-only changes, split/unified diff views, inline comments, and live auto-refresh.

Install

npm install -g diffhub

Or run without installing:

npx diffhub

Usage

Run inside any git repository:

diffhub

Opens http://localhost:2047 and shows tracked changes relative to your branch merge-base (main, master, develop, or dev, auto-detected).

# Use a different base branch
diffhub --base develop

# Point at a repo in another directory
diffhub --repo ~/projects/my-app

# Use a different port
diffhub --port 3000

# Don't open the browser automatically
diffhub --no-open

Features

• PR-style diff — defaults to merge-base diffs and also supports an uncommitted-only mode from the UI
• Split and unified views — toggle with s, keyboard-navigable with j / k
• Whitespace filtering — ignore whitespace-only changes from the top bar when reviewing formatting-heavy diffs
• Inline AI comments — add [must-fix], [suggestion], [nit], or [question] notes on any diff line; copy all comments as a formatted prompt
• "Open in" context menu — right-click any file to open in Zed, VS Code, Ghostty, Terminal, Finder, or copy the path
• Live refresh — polls for changes every 5 seconds; manual refresh with r
• File sidebar — filter files with /, see per-file +/- stats at a glance

Development notes

• The standalone CLI injects DIFFHUB_REPO into the Next.js server process.
• Local development can also point at a repo through DIFFHUB_REPO or the /tmp/diffhub-active-repo pointer file used by diffhub-point.
• The app ships a standalone Next.js build via bin/diffhub.mjs, not next start.

Keyboard shortcuts

| Key | Action | | --------- | --------------------------- | | j / k | Next / previous file | | s | Toggle split / unified view | | / | Focus file filter | | r | Refresh diff |

Options

| 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 |

Requirements

• Node.js 20.11+
• A git repository with at least one commit on your current branch

License

MIT