Leon - Your Open-Source Personal Assistant | WarmIndex

Leon is an open-source personal assistant that lives on your server, helping you automate everyday digital tasks through voice or text commands while ensuring complete privacy.

🚀 Overview

Leon addresses the privacy concerns and limitations of proprietary cloud-based assistants like Siri, Alexa, or Google Assistant by offering a fully self-hosted alternative that runs on your own hardware. It acts as a 'virtual brain,' handling tasks from simple queries to complex automations without sending data to third parties.

It's built for privacy-conscious users, self-hosters, developers, and anyone seeking a customizable AI companion they fully control. Whether you're automating home tasks, managing schedules, or experimenting with AI skills, Leon keeps everything local.

Louis Grenard created Leon in 2019 to pioneer an open-source, modular personal assistant under the permissive MIT license. The goal is to evolve it into an autonomous AI capable of self-improvement, local LLMs, and unlimited growth through community skills.

✨ Key Features

Modular skills architecture: Create, install, or share packages/modules (skills) to add functionalities like games, image recognition, or custom automations—no barriers to extension.
Multi-modal interaction: Voice support via STT/TTS (offline with Coqui, CMU Flite or cloud providers) and text-based input/output for flexible use.
Privacy-first design: Fully offline-capable, runs on your server to eliminate data leaks; user controls all aspects.
AI-powered core: Natural language processing (NLP), hotword detection, with upcoming local LLMs, workflow orchestration, ReAct reasoning, and self-coding skills.
Optional: Experimental features like video generation, hangman game, Speechmatics STT.

🛠 Tech Stack

Frontend: TypeScript (67%), JavaScript, Sass/SCSS (web interface)
Backend: Node.js (>=24.0.0), TypeScript, Python (22%) bridge/server
Database: TinyDB (for packages/modules)
Package Managers: pnpm (Node), uv (Python)
Other: FFmpeg, ESLint, Vitest (testing), Husky (git hooks), ONNX runtime (planned)
Auth: None (self-hosted personal use)
Hosting: Self-hosted

👥 Who Is This For?

This project is useful for:

Developers who want to build and share custom AI skills
Self-hosters looking for a private voice/text assistant
Privacy enthusiasts avoiding big tech surveillance

📸 Screenshots / Demo

Live demo: No public live demo (designed for self-hosting)
GitHub: https://github.com/leon-ai/leon
Demo videos: https://www.youtube.com/watch?v=p7GRGiicO1c, https://www.youtube.com/watch?v=6CInSt6pTVA

🔥 Project Status

🟢 Actively building

Last updated: 2026-03-24

❓ FAQ

Is this project free?

Yes / Open Source (MIT license). (Fully free to use, modify, and distribute.)

Is the source code available?

Yes — https://github.com/leon-ai/leon

Can I contribute?

Core contributions paused during major refactoring for stability. Help by creating/sharing skills, improving docs/translations, or joining Discord (https://discord.gg/MNQqqKg). Follow CONTRIBUTING.md.