Orbit Rust SDK

A complete Rust rewrite of OpenCode — the open-source AI coding agent.

We're rebuilding OpenCode from the ground up in 100% Rust for better performance, lower memory footprint, and a truly native experience.

Note: This is the open-source backend SDK derived from OpenCode. Orbit (our Unified Development Environment) is a separate, proprietary product that uses this SDK.

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Why Rust?

Aspect	TypeScript/Bun	Rust
Memory	~200-500MB runtime	~20-50MB
Startup	1-3 seconds	<100ms
Binary Size	Node/Bun runtime required	Single static binary
Native Integration	FFI overhead	Zero-cost Tauri integration
Concurrency	Event loop limitations	True parallelism with async/await

By rewriting in Rust, we get:

• Instant startup — no runtime initialization
• Minimal memory — critical for running alongside heavy IDEs
• Native Tauri integration — seamless desktop app without IPC overhead
• Single binary distribution — no dependencies, no node_modules
• True concurrency — parallel tool execution without blocking

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What is This?

Orbit Rust SDK is an open-source AI agent backend that handles:

• LLM provider communication (Anthropic, OpenAI, Google, AWS Bedrock, local models)
• Tool execution (bash, file operations, code analysis)
• Session management and conversation state
• Real-time streaming and event handling
• OAuth authentication flows (Claude Pro, ChatGPT Plus, GitHub Copilot)

This SDK is derived from OpenCode and is being rewritten in Rust. It's free and open source for the community to use, contribute to, and build upon.

Orbit (our Agentic UDE — Unified Development Environment) uses this SDK but is a separate, closed-source product.

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Current Status

Phase: Active Development

We're systematically converting the TypeScript codebase to Rust, crate by crate:

Crate	Status	Description
orbit-core	✅ Complete	ID generation, locks, timeouts, wildcard, filesystem, global paths
orbit-bus	🔄 In Progress	Event pub/sub system
orbit-storage	⬜ Planned	JSON file storage
orbit-project	⬜ Planned	Project/instance context
orbit-config	⬜ Planned	Configuration management
orbit-permission	⬜ Planned	Permission system
orbit-provider	⬜ Planned	AI provider adapters (Anthropic, OpenAI, Google, AWS)
orbit-session	⬜ Planned	Session management
orbit-tools	⬜ Planned	Agent tools (bash, read, write, edit, glob, grep)
orbit-lsp	⬜ Planned	LSP client integration
orbit-mcp	⬜ Planned	Model Context Protocol client
orbit-server	⬜ Planned	HTTP API with SSE

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Quick Start

# Check compilation
cargo check --workspace

# Run tests
cargo test --workspace

# Build release
cargo build --release

# Test crates during development
cargo run -p orbit-cli -- test-core

Development CLI

We provide a simple test CLI for verifying crates as they're built:

# Show available commands
cargo run -p orbit-cli -- help

# Test orbit-core
cargo run -p orbit-cli -- test-core

# More commands added as crates are completed

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Architecture

orbit-rust-sdk/
├── Cargo.toml                  # Workspace manifest
├── crates/
│   ├── orbit-core/             # Foundation utilities
│   ├── orbit-bus/              # Event pub/sub
│   ├── orbit-storage/          # JSON file storage
│   ├── orbit-project/          # Project/instance context
│   ├── orbit-config/           # Configuration
│   ├── orbit-permission/       # Permission system
│   ├── orbit-provider/         # AI provider adapters
│   ├── orbit-session/          # Session management
│   ├── orbit-tools/            # Agent tools
│   ├── orbit-lsp/              # LSP client
│   ├── orbit-mcp/              # MCP client
│   ├── orbit-server/           # HTTP API server
│   └── orbit-cli/              # Development test CLI
├── docs/
│   ├── conversion/             # Conversion planning docs
│   ├── providers/              # Provider auth documentation
│   └── workflow/               # Development workflow guides
└── OpenCode-reference/         # Original TypeScript source

Crate Dependency Graph

                    orbit-core
                    /    |    \
            orbit-bus  orbit-storage  orbit-config
                    \    |    /
                    orbit-project
                         |
                orbit-permission
                    /         \
           orbit-provider   orbit-tools
                    \         /
                   orbit-session
                    /    |    \
            orbit-lsp orbit-mcp orbit-server

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Documentation

Document	Description
docs/workflow/Workflow.md	Main conversion workflow guide
docs/workflow/MODULE_MAPPING.md	TypeScript → Rust module mapping
docs/providers/PROVIDER_AUTH.md	OAuth flows for Claude, Codex, Copilot
docs/providers/RUST_AI_SDK_ALTERNATIVES.md	Rust alternatives to Vercel AI SDK

Each crate also has a CONVERSION.md file mapping its TypeScript sources.

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Contributing

We welcome contributions! Whether you're:

• Porting TypeScript to Rust — Pick a module and start converting
• Adding features — New tools, providers, or improvements
• Fixing bugs — In either the TS or Rust codebase
• Improving docs — Better examples, guides, and explanations

This SDK is free and open source. Use it, fork it, build on it.

Conversion Workflow

1. Check crates/<crate-name>/CONVERSION.md for the TypeScript → Rust mapping
2. Follow the patterns in docs/workflow/Workflow.md
3. Test with cargo run -p orbit-cli -- test-<crate>
4. Submit a PR

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Acknowledgments

Special thanks to OpenCode and Anomaly (SST) for building the original open-source AI coding agent.

OpenCode proved that a fully open-source, provider-agnostic AI agent could rival proprietary solutions. We're taking their excellent work and rebuilding it in Rust to push performance even further.

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License

MIT License

Copyright (c) 2025 Recursive Labs Copyright (c) 2024-2025 SST/OpenCode (Original Work)

See LICENSE for details.

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Orbit Rust SDK
_{Built on the foundations of OpenCode}