CodeMantis — The Mac app Claude Code deserves
CodeMantis is a free, open-source native macOS application that provides a three-panel graphical interface for Anthropic's Claude Code CLI. Built with Tauri v2 and Rust, it launches in under 3 seconds, uses under 120MB of memory, and includes AI-powered spec writing, 10+ project templates, integrated terminals, and a live preview browser. Under 50MB download, MIT licensed.
Native macOS · Apple Silicon & IntelBuilt with Tauri v2 + RustSee it in action
CodeMantis in under 3 minutes
Write the Spec, Not the Code
Claude Code implements what you describe — but the quality of the description determines the quality of the result. SpecWriter is an AI conversation partner that draws out the details you'd forget to mention: loading states, error handling, validation rules, edge cases. It produces professional specification documents, verification checklists, and multi-session implementation plans. Then Self-Drive implements everything automatically — from idea to finished feature.
- Interactive multi-turn conversation
- Attach mockups, screenshots, and PDFs
- Reads your existing codebase and references real file paths
- Confidence tagging — the AI tells you when it's guessing
- Generates companion verification checklists
- Implementation Guide breaks specs into multi-session plans
- Self-Drive automates the entire implementation — build, verify, fix, advance
- Two modes: spec a new app from scratch, or add a feature to an existing project
See Everything at Once
Claude Code's power comes from its ability to read, write, and execute across your entire project. CodeMantis makes that visible. Chat conversations flow on the left. Every file read, write, edit, and bash command appears in the Activity Feed on the right — color-coded, expandable, with one-click approval. Choose Normal mode to approve each action, Auto-Accept to let Claude work freely, or Plan mode for reasoning-only conversations that never touch your code.
Start Projects in Seconds
Claude Code is at its best when it understands your project from the first message. CodeMantis gives it that head start. Pick from 10+ curated templates — Next.js, Vite+React, FastAPI, Astro, Expo, and more. One click scaffolds the project, installs dependencies, and generates a CLAUDE.md file that teaches Claude the project's structure, conventions, and commands. From empty folder to productive conversation in under a minute.
Preview Your App Live
A native macOS preview window shows your running application right alongside your Claude Code conversation. Auto-detects your dev server, supports responsive viewport presets — phone, tablet, desktop — and captures console logs so you can spot errors without switching to Chrome DevTools. It's the workflow you always wanted: describe a change, watch Claude implement it, see it live.
More Than One Brain
Sometimes you want a second opinion before committing to an approach. Open parallel AI assistants — the latest models from OpenAI, Google, or Anthropic — in tabs alongside your Claude Code session. Brainstorm architecture. Review code. Draft documentation. Compare suggestions. Each assistant has per-session cost tracking. Claude Code stays in control of your files; the assistants are your advisory board.
Everything in One Window
CodeMantis is a native Mac app built with Tauri v2 and Rust — not an Electron wrapper, not a web page in a frame. It launches instantly, uses minimal memory, and respects macOS conventions: native menus, keyboard shortcuts, proper window management. Inside that native shell: a Monaco code editor, xterm.js terminals, MCP server management for 15+ services, AI-powered changelogs, slash commands, and six carefully designed themes. Everything a Mac developer expects, nothing a Mac developer would compromise on.
What the Community Says
Early feedback from developers using CodeMantis with Claude Code.
I went from a terminal-only Claude Code workflow to CodeMantis and immediately felt the difference. Seeing the activity feed separate from the chat is a game-changer — I actually know what Claude is doing to my files now.
Early Beta Tester
Full-Stack Developer · Discord community
SpecWriter alone is worth the download. I used to spend 20 minutes writing prompts for Claude Code. Now I have a conversation with SpecWriter and get a proper spec in 5 minutes that Claude follows precisely.
Community Member
Product Engineer · Discord community
Finally a Claude Code interface that respects macOS conventions. It launches fast, uses minimal memory, and the three-panel layout makes so much more sense than a single scrolling terminal.
Community Member
macOS Developer · GitHub discussion
Frequently Asked Questions
Common questions about CodeMantis and how it works with Claude Code.
CodeMantis is a free, open-source native macOS application that provides a graphical interface for Anthropic's Claude Code CLI. It wraps Claude Code in a three-panel layout with a file tree, chat panel, and activity feed — plus integrated terminals, a file editor, AI-powered spec writing, and a live preview browser. Built with Tauri v2 and Rust, it launches in under 3 seconds and uses under 120MB of memory.
Yes, completely. CodeMantis is MIT licensed with no subscription fees, no API keys required, and no telemetry. You do need an existing Claude Pro ($20/month) or Claude Max ($100-200/month) subscription from Anthropic, since CodeMantis uses Claude Code under the hood — but CodeMantis itself costs nothing.
Claude Code in the terminal runs in a single scrolling pane where chat messages and tool operations are interleaved. CodeMantis separates these into dedicated panels: chat on the left, activity feed on the right. You also get a built-in file editor (Monaco), integrated terminals, a live preview browser, project templates, AI-powered spec writing (SpecWriter), and MCP server management — all in one native Mac window.
Cursor and VS Code extensions add AI to an existing code editor. CodeMantis takes the opposite approach: it builds a purpose-designed interface around Claude Code as the primary workflow. You get a dedicated activity feed showing every file operation, SpecWriter for creating implementation-ready specifications, session modes (Normal, Auto-Accept, Plan), and a native macOS app that uses 40-120MB of memory versus 300-500MB for Electron-based editors.
CodeMantis requires macOS 12 (Monterey) or later, on either Apple Silicon or Intel. You also need the Claude Code CLI installed (npm install -g @anthropic-ai/claude-code) and a Claude Pro or Max subscription. The app itself is under 50MB to download.
SpecWriter is an AI-powered specification assistant built into CodeMantis. Instead of giving Claude Code a vague prompt, SpecWriter guides you through an interactive conversation to extract every detail — loading states, error handling, validation rules, edge cases. It produces a structured specification document with a verification checklist. Two modes are available: New Application (from scratch) and Feature Mode (for existing projects, with codebase context).
Yes. CodeMantis includes Multi-AI Assistant tabs where you can run OpenAI, Google Gemini, or Anthropic API models alongside your Claude Code session. These assistants are chat-only (they cannot edit files or run commands) — perfect for brainstorming, code review, or getting a second opinion. Each assistant tracks per-session token usage and cost.
Yes. CodeMantis is released under the MIT License. The full source code is available on GitHub at github.com/codemantis-dev/codemantis. You can inspect the code, contribute features, report issues, or fork it.
Built by a creator.
Powered by Claude Code.
Made for creators.
AI coding enables a new dawn of creators. Ideas that were impossible due to budget, time, or team constraints are suddenly within reach. CodeMantis was built entirely by a non-developer using Claude Code itself — from the Rust backend to the React frontend — as proof that the path from idea to product is now open to everyone.
CodeMantis exists to support that journey. Not for the engineers who already know how to code, but for the innovators who finally can.
Free. Open source. Built for Mac.
CodeMantis is MIT licensed. No API keys, no subscription fees, no telemetry. Just download, connect to your Claude Pro or Max subscription, and start building. The best coding AI in the world, with the interface it's been missing.