diffmark

diffmark is a terminal UI for reviewing uncommitted Git changes and turning selected diff lines into inline comments you can paste into a command-line AI agent.

It watches staged and unstaged tracked changes, and shows untracked files by default.

Repository: https://github.com/su27/diffmark

Install

Prebuilt installers are available from GitHub Releases.

Linux/macOS:

curl --proto '=https' --tlsv1.2 -LsSf https://github.com/su27/diffmark/releases/latest/download/diffmark-installer.sh | sh

Windows PowerShell:

powershell -ExecutionPolicy Bypass -c "irm https://github.com/su27/diffmark/releases/latest/download/diffmark-installer.ps1 | iex"

Rust users can also build from crates.io:

cargo install diffmark

Building from source requires Rust 1.88 or newer.

For local development:

cargo install --path .
cargo run --release -- --context 5 --refresh 1.0 --max-copy-lines 11

Usage

diffmark

Common options:

diffmark --context 5
diffmark --refresh 1.0
diffmark --max-copy-lines 11
diffmark --no-untracked
diffmark --max-untracked-bytes 1048576
diffmark -- src/app.rs README.md

Notes:

• Untracked files are shown by default; use --no-untracked to hide them.
• Untracked files larger than 1 MiB are skipped by default; use --max-untracked-bytes to change the limit.
• Path arguments after -- limit the diff to those files or directories.

Controls

• j / k: move the selection; in visual mode, extend the selected range
• V: enter or leave visual-line mode
• Enter: comment on the selected line/range, or edit the selected comment row
• f / b: page forward/backward
• g / G: jump to top/bottom
• r: refresh now
• Esc: leave visual mode or cancel comment editing
• q: quit

Mouse controls:

• Wheel: scroll
• Click a diff line: comment on that line
• Drag across diff lines: select a range, then comment on it
• Click a comment row, then press Enter: edit that comment

Comment editor

The editor appears inline under the selected diff line or block.

• Enter: submit the comment, copy the payload, and show the inline comment
• Ctrl-J: insert a new line
• Esc: cancel
• Arrow keys, Backspace, Delete, Home, End: edit text

Clipboard

When a comment is submitted, diffmark copies a review payload using the first available method:

1. WSL/Windows clipboard: clip.exe or powershell.exe
2. Linux/macOS tools: wl-copy, xclip, xsel, pbcopy, or termux-clipboard-set
3. OSC52 terminal clipboard escape sequence, including tmux passthrough
4. Fallback file: /tmp/diffmark-last-comment.txt

Use --no-osc52 to disable the OSC52 fallback.

Copied payload

The copied text includes:

• file path and target line number or line range
• your comment
• a compact diff snippet around the selected line/range
• >> target: for single-line selections
• >> target start / >> target end for multi-line selections
• >> comment: immediately after the selected line/block

Privacy

diffmark does not send data over the network. It only runs git, reads local files when rendering untracked changes, and calls local clipboard tools.

Development

cargo fmt --check
cargo clippy --all-targets --locked -- -D warnings
cargo test --locked
cargo package --locked