Oyo

A diff viewer for stepping through changes and reviewing scrollable diffs.

https://github.com/user-attachments/assets/0f43b54b-69fe-4cf3-9221-a7749872342b

Oyo is a terminal diff viewer.

Use it as a normal scrollable diff viewer, or step through changes one at a time. You can switch between both modes at any time.

Choose a review mode

Scroll-only diff

Use scroll-only mode when you want a traditional diff viewer.

You can:

• review all changes at once
• scroll freely
• jump between hunks

Start with:

oy

Step-through diff

Use step-through mode when you want to see how a file changes over time. This helps with large refactors and careful reviews.

Start with:

oy --step

You can also press s in the TUI, or set stepping = true in config.

Features

• scroll-only diff mode
• step-through navigation
• hunk navigation
• unified, split, evolution, blame and preview views
• tabs for multiple views
• mouse support
• Markdown, JSON, YAML, TOML and CSV previews
• inline review comments
• visual text selection with copy, comments and command actions
• word-level diffing
• multi-file navigation
• watch mode that refreshes changed files on disk
• regex search
• syntax highlighting
• blame hints
• command palette
• line wrap
• context folding
• animated transitions
• autoplay
• Git integration
• commit picker with oy view
• built-in themes and .tmTheme syntax themes
• XDG config file support

Install

npm

npm i -g @ahkohd/oyo

Pi package

This gives you the /diff and /review commands.

pi install npm:@ahkohd/pi-oyo

Homebrew

brew install ahkohd/oyo/oy

Arch Linux

paru -S oyo

Cargo

cargo install oyo --locked --force

Use Oyo

Show uncommitted changes

oy

Step through uncommitted changes

oy --step

Compare 2 files

oy old.rs new.rs

Compare one file with HEAD

oy path/to/file.rs

Show staged changes

oy --staged

Show a Git range

oy --range HEAD~1..HEAD
oy --range main...feature

Choose a view mode

oy old.rs new.rs --view split
oy old.rs new.rs --step --view evolution

Use autoplay

oy old.rs new.rs --step --autoplay
oy old.rs new.rs --step --speed 100

Pick a commit range

oy view

Review comments

Add comments while reviewing. Oyo prints them when you quit.

oy

Write comments to a file:

oy --review-output-file /tmp/oy-review.txt

Write comments only to a file:

oy --review-output-file /tmp/oy-review.txt --no-print-review

Disable persisted review sessions:

oy --no-review-persist

Start a fresh persisted review session:

oy --clear-review-session

Review hooks are documented in review hooks.

Use with Git

Use git difftool:

git difftool -y --tool=oy

Add this to ~/.gitconfig:

[difftool "oy"]
    cmd = oy "$LOCAL" "$REMOTE"

[difftool]
    prompt = false

[alias]
    d = difftool -y --tool=oy

Keep your pager, such as less, moar or moor, for git diff.

Do not set core.pager or interactive.diffFilter to oy.

Use with Jujutsu

Add this to your Jujutsu config:

[ui]
paginate = "never"
diff-formatter = ["oy", "$left", "$right"]

[diff-tools.oy]
command = ["oy", "$left", "$right"]

Keybindings

Most navigation commands support counts. For example, 10j moves 10 steps forward and 5J scrolls down 5 lines.

Common defaults:

Full keybinding and mouse reference: keybindings.

Selection works with mouse drag or v, V and ctrl-v. Press y to copy and esc to clear.

Clipboard support first uses system tools:

• pbcopy on macOS
• wl-copy, xclip or xsel on Linux
• clip on Windows

If those fail, Oyo falls back to OSC 52 terminal clipboard support.

Configure Oyo

Create a config file at ~/.config/oyo/config.toml.

You can also pass extra config files with repeatable --config FILE. Oyo loads your user config first, then merges each extra config file in order.

oy --config /tmp/oyo-plugin.toml

Minimal config:

[ui]
view_mode = "unified"
stepping = false
watch = true
line_wrap = false
fold_context = "off"

[ui.diff]
fg = "syntax"
bg = true
highlight = "word"

[ui.syntax]
mode = "on"

[files]
panel_visible = true
panel_width = 30
panel_position = "left"

Config is loaded from the first matching file:

1. $XDG_CONFIG_HOME/oyo/config.toml
2. ~/.config/oyo/config.toml
3. the platform config directory, such as ~/Library/Application Support/oyo/config.toml on macOS

Use these docs for full configuration:

• config reference
• theme configuration
• keybinding actions
• review hooks
• diff behaviour
• diff styling previews

Diff styling previews include screenshots.

Development

cargo build
cargo test
cargo run --bin oy -- old.rs new.rs