A native macOS GUI for Jujutsu (jj) — fast, keyboard-driven, built with Rust + SwiftUI.

Browse your DAG, review side-by-side diffs, resolve conflicts, and run every jj operation from one window. JayJay is a full-featured jj GUI with DAG visualization, interdiff (PR-style revision comparison), diff edit mode, file annotate, one-click conflict resolution, AI-generated commit messages, and a command palette.

History & Graph

• DAG visualization with lane-based fork/merge rendering
• Bookmark and conflict indicators on every node
• Revset filtering with preset chips (All, Mine, Bookmarks, Trunk, Conflicts, Heads)
• Load more: incrementally load older history
• Auto-refresh via file system watcher

Diff & Review

• Unified + side-by-side diff modes (toggle with one click)
• Histogram diff algorithm (via jj-diff crate) — instant diffs even for large files
• Diff edit mode (jj diffedit-style): select files, hunks, or line ranges across a change
• Interdiff: compare any two revisions (shift-click or context menu)
• File annotate (blame) with syntax-highlighted gutter — click to navigate
• File history: list all revisions that modified a file
• tree-sitter syntax highlighting (18 languages)
• Word-level change highlighting
• Context collapsing, rename detection
• Background preloading of all file diffs
• Persistent file review state (survives restart, auto-invalidates on content change)

Conflict Resolution

• Conflicted files shown with warning indicator and resolution bar
• One-click "Use Ours" / "Use Theirs" resolution
• "Resolve in Editor" via jj resolve --tool (VS Code, Zed merge editors)
• Auto-refresh after resolution

Operations

• New, edit, describe, squash, abandon, split (with parallel option), graft, duplicate, merge
• Extract selected diff to child/parallel changes, move selected changes to @, discard selected working-copy changes
• Absorb hunks into ancestors, back out (revert) changes
• Git push/fetch with auto-track
• Bookmark Manager (⌘⇧B) with stats, filter, clean up stale branches, resolve conflicts
• Divergent commit detection and resolution
• Undo via operation log
• Command palette (⌘⇧P) with ~35 commands and jj CLI integration

AI Commit Messages

• Codex CLI, Claude CLI, Apple Intelligence fallback chain

Tools & Settings

• External editor integration (VS Code, Zed, Xcode, Android Studio, Vim + auto-detection)
• Terminal integration (Terminal.app, iTerm2, Ghostty)
• Dock menu with recent repositories
• Font family picker + ⌘+/-/0 zoom
• Commit avatars (GitHub + Gravatar)
• Multi-window, recent repos, CLI launcher with URL scheme

Homebrew:

brew install --cask hewigovens/tap/jayjay

Download: Grab the latest release from GitHub Releases, unzip, and move to Applications.

Build from source:

just run               # Build and run
just install-cli       # Install CLI launcher to ~/.local/bin
jayjay .               # Open current repo

Auto-update: JayJay checks for updates automatically via Sparkle. You can also check manually from JayJay → Check for Updates. Auto-update may require App Management permission in System Settings → Privacy & Security.

Requirements: macOS 26 (Tahoe) recommended.

See Roadmap.md for near-term and long-term plans.

See CONTRIBUTING.md for architecture notes, development workflow, and the current jj-lib vs jj CLI backend split.

The diff engine is extracted as a standalone Rust crate with zero dependency on jj-lib:

[dependencies]
jj-diff = { git = "https://github.com/hewigovens/jayjay" }

Features:

• Histogram line diff (via similar 3.0)
• Word-level diff highlighting
• tree-sitter syntax highlighting (18 languages)
• Context collapsing with display-to-full line index mapping
• Skip highlighting for .lock/.csv/.svg files

Usage:

use jj_diff::{compute_file_diff, collapse_context_with_mapping};

let diff = compute_file_diff("main.rs", &old_content, &new_content, false);
let collapsed = collapse_context_with_mapping(&diff);
for line in &collapsed.diff.lines {
    // render line with line.style, line.spans
}

What is JayJay? JayJay is a native macOS GUI for Jujutsu (jj), the modern version control system that reimagines the git model with mutable history, changes instead of commits, and bookmarks instead of branches. JayJay is built with Rust (wrapping jj-lib directly — no CLI scraping) and SwiftUI.

Is there a GUI for Jujutsu? Yes — JayJay is a full-featured native macOS jj GUI. It gives you DAG visualization, unified + side-by-side diffs with tree-sitter syntax highlighting, interdiff (PR-style revision comparison), diff edit mode, file annotate, one-click conflict resolution, and every common jj operation (squash, split, graft, absorb, backout, merge, duplicate, describe, abandon) — without memorizing the command flags.

How do I install JayJay on macOS? brew install --cask hewigovens/tap/jayjay is the easiest path. Or download the signed, notarized zip from GitHub Releases. Requires macOS 15 Sequoia or later.

Does JayJay support interdiff (comparing two revisions)? Yes. Shift-click two revisions in the DAG to compare them PR-style — same unified + side-by-side diff views with word-level highlighting, but rendering the difference between the two change contents.

Does JayJay support side-by-side diffs? Yes. Toggle between unified and side-by-side diff modes with one click. Both use tree-sitter syntax highlighting (18 languages) and word-level change highlights. Image files (PNG, JPG, SVG, HEIC, …) render as actual images with before/after panes, not as <binary> placeholders.

Can JayJay extract individual lines or hunks into a new change? Yes — this is JayJay's diff edit mode. Select files, hunks, or line ranges across a change and split them out into a new child or parallel change (jj diffedit workflow). You can also right-click → Abandon Selected Lines on the working copy to drop individual edits.

How is JayJay different from using jj on the command line? JayJay doesn't replace the jj CLI — it complements it. The DAG graph, visual diff review, diff-edit mode, and bookmark manager are significantly easier in a GUI than in a terminal. For anything JayJay doesn't expose, the command palette (⌘⇧P) has an ! prefix that drops you into a raw jj CLI prompt in-window.

Is JayJay open source? JayJay is free and source-available, not OSI open source. The macOS app is BSL 1.1 — free to use, fork, modify, and redistribute; the only restriction is paid app-store distribution without permission. It converts to Apache-2.0 on 2030-03-23. The Rust crates (jayjay-core, jayjay-uniffi, jj-diff) are Apache-2.0 today.

Does JayJay work on Windows or Linux? Not yet. Today it's macOS-only. The Rust core (jayjay-core) is platform-agnostic — a future Windows or Linux frontend is possible if there's demand.

• Rust crates (crates/): Apache-2.0
• macOS app (shell/, everything else): BSL 1.1 — free to use, modify, and redistribute; paid app store distribution requires permission. Converts to Apache-2.0 on 2030-03-23.