lziff

A cross-platform terminal diff & review tool with JetBrains-style snap-aligned side-by-side diffs.

Demo Screenshot

File diff	Screenshot
View Diff

Review Mode	Screenshot
Select PR
PR diff
Review / Comment
Submit Review

What it does

• Side-by-side diff of two files or any pair of git states.
• Snap alignment: click any line and the other pane scrolls until the corresponding line lands on the same row. Equal anchors stay visually connected by ●─● ribbons in the gutter.
• No filler rows: each pane shows its file as-is. When one side has more change than the other, scrolling automatically pauses the shorter side at change-block boundaries so the panes re-sync at the next equal anchor.
• Word-level highlights inside modified lines, with a similarity threshold so unrelated pair-ups don't turn into red/green noise.
• Auto-reload while you edit — saves outside the tool show up within a couple hundred milliseconds.
• Mouse + keyboard: click to snap, wheel to scroll the pane under the pointer, vim-style keys for everything else.

Install

Homebrew (macOS / Linux)

brew install KikuchiTomo/tap/lziff

cargo (crates.io)

cargo install lziff

From source (Rust 1.74+)

cargo install --git https://github.com/KikuchiTomo/lziff

Pre-built binaries

Download the latest binary for your platform from the Releases page and put it somewhere on your $PATH.

Usage

Git workflows

lziff                          # working tree vs HEAD/index (default)
lziff --staged                 # staged changes (index vs HEAD; alias: --cached)
lziff --commit HEAD            # what HEAD changed (HEAD~ vs HEAD)
lziff --commit abc123          # what an arbitrary commit changed
lziff --range main..feature    # what `feature` added on top of `main`

Run lziff anywhere inside a git repository and it picks up the repo automatically. The Files panel on the left lists every changed file; pick one with j/k (or click), then explore the diff on the right.

Arbitrary file pair

lziff a.txt b.txt              # diff any two files, no git required

The Files panel hides itself in this mode so the diff fills the screen.

Live editing loop

Run lziff in one terminal and edit in another — saves are picked up automatically and the diff redraws in place. Useful when you want to review your in-progress changes without alt-tabbing through git diff.

Keys

Key	Action
j / k	scroll both panes 1:1
J / K	jump to next / previous change hunk
Ctrl-d/u	half-page down / up
g / G	top / bottom
n / p	next / previous file
click	select that line; the other pane snaps to it
wheel	scroll the pane under the pointer
=	re-snap the non-anchor pane to the cursor row
Tab	toggle focus (Files / Diff)
F	show / hide the Files panel
r	manual reload
?	open this help
q	quit

Configuration

lziff reads $XDG_CONFIG_HOME/lziff/config.toml (or the platform equivalent — e.g. ~/Library/Application Support/lziff/config.toml on macOS). The file is optional; missing keys fall back to sensible defaults.

[i18n]
lang = "ja"                    # "en" or "ja" — defaults to $LANG

[layout]
files_panel_width_pct = 20     # % of horizontal space for the Files list
ribbon_width = 5               # 5-char gutter between the two diff panes
target_y_divisor = 3           # alignment row sits at viewport_h / N

[behavior]
tick_ms = 250                  # auto-reload poll interval
scroll_step = 3                # mouse-wheel step
half_page_step = 15            # ctrl-d / ctrl-u step
similarity_threshold = 0.30    # below this, paired lines drop word-diff

# Rebind any of the 19 actions. Override accepts a single string or an
# array. Modifiers: ctrl-, shift-, alt-. Named keys: Up, Down, Left,
# Right, Enter, Esc, Tab, F1..F12, PageUp, PageDown.
[keymap]
quit         = ["q", "Esc"]
scroll_down  = ["j", "Down"]
scroll_up    = ["k", "Up"]
next_hunk    = "J"
prev_hunk    = "K"
half_page_down = "ctrl-d"
half_page_up   = "ctrl-u"
toggle_help    = "?"
toggle_files_panel = "F"
resnap         = "="

# Every visual color is themable via #rrggbb. Below is just a sample;
# all theme keys are documented in the config module.
[theme]
bg_delete = "#301618"
bg_insert = "#142c1a"
hl_delete = "#963c46"
hl_insert = "#328246"
anchor_bright = "#f5f5fa"
help_section_fg = "#e1c882"

Status

Early days — the diff engine and snap UX are stable, but the plugin boundary (for hosting non-git sources) is still in design. Issues and suggestions welcome on the issue tracker.