zz

WIP — This project is under active development. Expect bugs, missing features, and breaking changes.

A lightweight, fast code editor written in Zig. No AI, no telemetry, no bloat.

 ┌─ zz ──────────────────────────────────────────────┐
 │ [main.zig] [view.zig] [+]                         │
 ├─ ▾ src/    ─┬──────────────────────────────────────┤
 │   ▾ editor/ │  1 │ const std = @import("std");     │
 │     buffer  │  2 │                                 │
 │     cursor  │  3 │ pub fn main() !void {           │
 │     view    │  4 │     // ...                      │
 │   ▾ ui/     │  5 │ }                               │
 │     window  │                                      │
 │     font    ├──────────────────────────────────────┤
 │     render  │  master │ Zig │ Ln 3, Col 5 │ UTF-8  │
 ├─────────────┼──────────────────────────────────────┤
 │ $ zig build                                        │
 │ Build succeeded.                                   │
 └────────────────────────────────────────────────────┘

Why

• VS Code / Zed: Feature-rich but heavy, ships AI and telemetry
• Neovim / Helix: Fast but no native GUI, no mouse-first UX
• zz: Fast GUI editor with zero telemetry. 3MB binary, 18MB RAM, idle CPU 0%

Features

Editor Core

• Piece Table buffer with O(1) insert and undo/redo coalescing
• Multi-cursor editing (Ctrl+D, Ctrl+Shift+L)
• Split panes (vertical/horizontal, binary tree layout)
• Tabs with multi-file editing
• Auto-indent on Enter (copies whitespace, extra indent after {)
• Line operations (duplicate, move up/down, delete)
• Bracket matching with highlight and auto-closing
• Word occurrence highlighting on cursor
• Indent guides (vertical lines at tab stops)
• Trailing whitespace visualization and trim-on-save
• Smart selection (Ctrl+Shift+Up/Down expand/shrink)
• 4 themes: Catppuccin Mocha, Tokyo Night, Gruvbox Dark, One Dark
• UTF-8 with CJK wide character support
• XIM/fcitx5 input method for Japanese/Chinese

Rendering

• xcb + SHM direct framebuffer (no GPU, no compositor dependency)
• FreeType font rendering with glyph cache (ASCII pre-rendered)
• Catppuccin Mocha theme with syntax-colored highlights
• Dirty region tracking (only re-renders changed rows)
• Event-driven rendering (0% CPU when idle)

IDE

• Tree-sitter syntax highlighting (C, Python, Rust, JavaScript, Bash)
• LSP integration (zls, clangd, rust-analyzer auto-detected)
• Diagnostics underlines (error/warning/info severity colors)
• F12 go-to-definition (same file jump + cross-file open)
• Ctrl+P fuzzy file finder (.gitignore aware)
• Ctrl+Shift+P command palette
• Ctrl+F text search with wrap-around
• Ctrl+H find and replace
• Ctrl+Shift+F search across project files
• Ctrl+Shift+O go to symbol (LSP document symbols)
• Code folding (Ctrl+Shift+[) with bracket matching
• Minimap code overview with syntax colors
• F2 rename symbol, Ctrl+. code actions, Shift+F12 references
• LSP signature help (auto-trigger on ( and ,)
• F8 / Shift+F8 navigate diagnostics

Extras

• File tree sidebar (Ctrl+B) with expand/collapse
• Git branch name + diff gutter (added/modified/deleted markers)
• Embedded terminal (Ctrl+`) with full VT parser, xterm-256color, ANSI/truecolor

Requirements

Arch Linux x86_64 with:

# Build dependencies
sudo pacman -S zig

# Runtime dependencies (most already installed on a desktop system)
sudo pacman -S libxcb xcb-util-xrm xkbcommon xcb-imdkit freetype2

# Tree-sitter (syntax highlighting)
sudo pacman -S tree-sitter tree-sitter-c tree-sitter-python tree-sitter-rust tree-sitter-javascript tree-sitter-bash

# LSP servers (optional, for IDE features)
sudo pacman -S zls               # Zig
# clangd included with clang
# rust-analyzer included with rustup

Build

git clone https://github.com/midasdf/zz.git
cd zz
zig build                        # Debug build
zig build -Doptimize=ReleaseFast  # Release build (~4MB)

Usage

./zig-out/bin/zz                  # New empty buffer
./zig-out/bin/zz file.zig         # Open a file
./zig-out/bin/zz src/main.zig     # Edit your own source

Keybindings

Key	Action
File
Ctrl+S	Save
Ctrl+P	Fuzzy file finder
Ctrl+Q	Quit
Edit
Ctrl+Z	Undo
Ctrl+Shift+Z	Redo
Ctrl+C / X / V	Copy / Cut / Paste
Ctrl+A	Select all
Ctrl+D	Select next occurrence
Ctrl+Shift+L	Select all occurrences
Esc	Collapse multi-cursor
Navigate
Ctrl+G	Go to line
Ctrl+F	Find
Ctrl+Shift+P	Command palette
F12	Go to definition
View
Ctrl+Tab	Next tab
Ctrl+Shift+Tab	Previous tab
Ctrl+W	Close tab
Ctrl+\	Split vertical
Ctrl+Shift+\	Split horizontal
Ctrl+B	Toggle file tree
Ctrl+`	Toggle terminal
Search
Ctrl+Shift+F	Search in project
Ctrl+H	Find & replace
Code
Ctrl+Space	Trigger completion
Ctrl+Shift+I	Format document
Ctrl+Shift+D	Duplicate line
Alt+Up / Down	Move line up / down
Ctrl+Shift+K	Delete line
Ctrl+Shift+O	Go to symbol
Ctrl+Shift+[	Toggle code fold
Ctrl+/	Toggle line comment
Ctrl+L	Select line
Ctrl+J	Join lines
Ctrl+Enter	Insert line below
Ctrl+Shift+Enter	Insert line above
F2	Rename symbol
Ctrl+.	Code actions
Shift+F12	Go to references
F8 / Shift+F8	Next / prev diagnostic
Ctrl+Backspace	Delete word left
Ctrl+Delete	Delete word right
Tab (selection)	Indent lines
Shift+Tab	Outdent lines
Ctrl+Home / End	Start / end of file
Ctrl+Up / Down	Scroll without cursor
Ctrl+M	Go to matching bracket
Ctrl+Shift+Up / Down	Expand / shrink selection

Architecture

src/
├── main.zig              Event loop, mode dispatch
├── editor/
│   ├── buffer.zig        Piece Table with undo/redo
│   ├── cursor.zig        Multi-cursor, UTF-8 movement
│   ├── view.zig          Editor rendering, diagnostics
│   ├── highlight.zig     Tree-sitter integration
│   ├── tabs.zig          Tab manager
│   └── panes.zig         Split pane binary tree
├── ui/
│   ├── window.zig        xcb + SHM, keyboard, clipboard, XIM
│   ├── font.zig          FreeType glyph cache
│   ├── render.zig        Pixel rendering (BGRA32)
│   ├── overlay.zig       Command palette / finder popup
│   ├── file_tree.zig     Directory tree sidebar
│   └── terminal.zig      VT terminal emulator
├── lsp/
│   └── client.zig        LSP JSON-RPC client
├── core/
│   ├── fuzzy.zig         Fuzzy matching algorithm
│   ├── file_walker.zig   Directory walker (.gitignore)
│   └── git.zig           Git branch + diff info
└── input/
    └── keymap.zig        Keybind mapping

~16,000 lines of Zig. Zero external Zig dependencies.

All rendering is CPU-based (xcb shared memory). No GPU, no OpenGL, no Wayland (yet). Single-threaded epoll event loop. The only subprocess communication is with LSP servers (JSON-RPC over stdin/stdout) and the embedded terminal (PTY).

Stats

Metric	Value
Binary (ReleaseFast)	4.1 MB
Binary (ReleaseSmall + strip)	~240 KB
Memory (RSS)	~18 MB
Idle CPU	0%
Startup time	Instant (mmap + single piece)
Source lines	~16,000
Dependencies (Zig packages)	0

License

MIT