An AI agent for Unity that escapes the editor

What it does

Locus is a standalone AI agent for Unity development, built in Rust with a Vue.js frontend. It writes C# code, modifies scenes and assets, debugs runtime state via reflection, and tracks changes through a visual version-control interface. It runs as its own process on Windows, talking to the Unity Editor rather than living inside it.

The interesting bit

The authors argue that an in-editor plugin or MCP server could never pull this off. By staying outside, Locus uses Roslyn to JIT-compile C# inside Unity, performs parallel asset-database scans in Rust, and embeds a full Vue.js UI into the Unity window through Windows APIs. It also maintains long-term project memory with configurable document-injection levels, which is the kind of feature that sounds dull until you realize it saves the agent from re-exploring your project every session.

Key highlights

• Standalone Rust + Tauri + Vue.js app that operates outside the Unity Editor process.
• JIT-compiles and executes C# inside Unity via Roslyn for semantic asset edits.
• Parallel asset-database scanning and a proprietary intermediate representation for large scenes.
• Runtime state sampling via C# reflection, outputting frame-by-frame tables for debugging.
• Automated knowledge system with long-term memory and configurable L0/L1/L2 document injection.

Caveats

• Windows and Unity 2021+ only; macOS support is planned but not yet available.
• The project is in early testing (v0.2.8), so expect rough edges.

Verdict

Unity developers who want an AI collaborator with deep project memory and runtime debugging should keep an eye on this. Everyone else can wait for the cross-platform release.