My name is deff

deff

deff is a Rust TUI: interactive, side-by-side file review for git diffs with per-file navigation, vertical and horizontal scrolling, syntax highlighting, and added/deleted line tinting.

Quickstart

Choose one install method:

1. Install from crates.io with Cargo:

cargo install deff

2. Run the installer script from this repository:

curl -fsSL https://raw.githubusercontent.com/flamestro/deff/main/install.sh | bash

Installer script source: https://github.com/flamestro/deff/blob/main/install.sh

The script checks for cargo, clones this project into a temporary directory, installs it, and removes the temporary checkout. Bundled syntax grammars are compiled into the binary, so removing the checkout does not affect highlighting.

If you have local edits (including untracked files) and want to review them before committing, run:

deff --only-uncommitted

This opens the side-by-side review so you can check exactly what changed in your working tree.

Features

• upstream-ahead strategy (default) to compare local branch changes against its upstream
• range strategy for explicit --base / --head comparison
• Optional --include-uncommitted mode to include working tree and untracked files
• --only-uncommitted mode to compare working tree and untracked files against HEAD
• Side-by-side panes with independent horizontal scroll offsets
• Keyboard and mouse navigation (including wheel + shift-wheel)
• Vim-like motion navigation (h/j/k/l, g/G, Ctrl+u/Ctrl+d)
• Configurable key bindings
• In-diff search (/ + Enter, then n / N to navigate matches)
• Per-file reviewed toggles (r) with local persistence under .git
• Language-aware syntax highlighting and line-level add/delete tinting

Examples

Single-line change view:

Multi-line change view:

Usage

deff
deff --strategy upstream-ahead
deff --strategy range --base origin/main --head HEAD
deff --strategy range --base origin/main --include-uncommitted
deff --only-uncommitted
deff --theme dark
deff --config ~/.config/deff/config.toml

Show help:

deff --help

Local Build and Usage Flow

Prerequisites:

• Rust toolchain (cargo)
• git
• Interactive terminal (TTY)

1. Build locally:

   cargo build --release --locked
   ./target/release/deff --help
   

2. Optionally install it to your local Cargo bin path:

   cargo install --path .
   deff --help
   

3. Run it inside any git repository you want to review:

   cd /path/to/your/repo
   
   # default: compare local branch commits vs upstream
   deff
   
   # explicit range
   deff --base origin/main --head HEAD
   
    # include uncommitted + untracked files
    deff --base origin/main --include-uncommitted
   
    # compare only working tree + untracked files against HEAD
    deff --only-uncommitted
   

If your branch has no upstream configured, use the explicit --base flow.

Theme selection:

• By default, deff prefers a dark syntax theme (better for black/dark terminals).
• Use --theme auto|dark|light to control rendering for your terminal.
• --theme takes precedence over DEFF_THEME=dark|light.

Key binding config:

• Default filesystem locations: ~/.config/deff/config.toml or $XDG_CONFIG_HOME/deff/config.toml
• --config <path> to load specific config file
• --no-config to ignore config files
• Supported actions: quit, previous_file, next_file, scroll_up, scroll_down, page_up, page_down, top, bottom, search, next_match, previous_match, next_hunk, previous_hunk, toggle_reviewed
• Key names: printable characters ("j"), arrows ("left"), paging keys ("pageup"), modifiers ("ctrl-u", "alt-j")
• Entries under [keybindings] replace that action's defaults; omitted actions keep default bindings

[keybindings]
page_down = "J"
page_up = "K"

Custom syntax grammars:

• deff loads syntect defaults, bundled deff grammars, plus any extra .sublime-syntax files found in:
  • assets/syntaxes (current working directory)
  • .deff/syntaxes (current working directory)
• Any *.sublime-syntax file added under this repo's assets/syntaxes is auto-bundled at build time.

Search and reviewed workflow:

• Press / to enter a search query for the current file (searches both panes).
• Press Enter to apply the query, then use n / N to jump matches.
• Press r to mark the current file reviewed/unreviewed.
• Reviewed state is persisted locally in .git/deff/reviewed/ and keyed by comparison scope + file content hash.

GitHub Version Bump Workflow

This repo ships with .github/workflows/bump-version.yml.

• Trigger: push to main (excluding commits authored by github-actions[bot])
• Computes the next version from commit prefixes (feat: -> next minor, fix:/chore:/docs: -> next patch) and updates Cargo.toml/Cargo.lock when needed
• Publishes new crate versions to crates.io and then creates/pushes the matching vX.Y.Z tag and GitHub release

Contributing

See CONTRIBUTING.md for local setup, commit message conventions, and release/versioning rules.

Architecture and Extension Guide

For a module-level map and extension plan, see docs/architecture.md.