OpenCode

OpenCode is an open-source terminal coding agent published by Anomaly Innovations, formerly the SST (Serverless Stack) team. The project ships under MIT license at github.com/sst/opencode and is organized as a Bun workspace monorepo with 20-plus packages and Turbo build orchestration; the Go SDK published on pkg.go.dev indicates a Go component in the backend stack. The TUI is designed by Neovim users, which is visible in the keyboard-first interaction model. The project has accumulated tens of thousands of GitHub stars since its mid-2025 release.

The architecture is client-server: a persistent local server process holds session state and connects to LLM providers, while a TUI client, a desktop app, a VS Code extension, or a web UI talks to it over the local socket. Sessions survive terminal disconnects, SSH drops, and machine sleep; reconnecting picks up where the previous session left off. The model layer abstracts over 75-plus LLM providers including Anthropic, OpenAI, Google, and local model runners. Two built-in agents ship: build (full read-write access) and plan (read-only, for analysis and exploration), toggled via Tab. Language Server Protocol integration provides language-aware navigation and diagnostics for the agent.

Distribution-wise, opencode-sdk-go on pkg.go.dev exposes the API for embedding the agent into other Go programs. The mobile-first portal project (github.com/hosenur/portal) provides a web UI with git integration and in-browser terminal, illustrating that the client-server split enables non-Anomaly teams to ship their own front ends against the same backend.

HRF awarded OpenCode in the November 24, 2025 AI for Individual Rights round. The grant funds work on the platform's use by civil-society teams under authoritarian rule, where routing sensitive software work through corporate AI infrastructure is a surveillance risk. The local-first runtime is the structural defense: code that never leaves the developer's machine cannot be subpoenaed from a vendor, and the open codebase lets security teams audit what the agent actually does before deploying it on sensitive repositories. The competing alternatives are Claude Code, Cursor, GitHub Copilot, and Aider; OpenCode's differentiation is the provider-agnostic backend plus the client-server split that lets the same agent state serve a TUI, an IDE, and a mobile client.