Best Open Source AI Coding Tools 2026

Only OSS tools — license, GitHub stars, language, and honest strengths. No SaaS wrappers. Last updated July 2026.

ToolLicenseLanguageTypeModel provider
amuxMIT + Commons ClausePythonFleet orchestratorAny (Claude Code, Codex, Gemini CLI)
AiderApache 2.0PythonTerminal agentAny LLM (incl. local Ollama)
Cline / Roo CodeApache 2.0 / MITTypeScriptVS Code extensionAny (Claude, GPT-4, Gemini, local)
OpenHandsMITPythonAutonomous agent + sandboxClaude, GPT-4, local
Continue.devApache 2.0TypeScriptIDE extension (VS Code + JetBrains)Any (50+ model providers)
Goose (Block)Apache 2.0RustTerminal agentClaude, GPT-4, local
Antigravity CLI (agy)MITGoTerminal agentGemini 2.5 (Google)
Claude Code CLIMIT (CLI tooling)TypeScriptTerminal agentClaude only (Anthropic API)

amux — Fleet orchestrator

amux is the only tool on this list focused purely on orchestration rather than being a coding agent itself. It manages fleets of Claude Code, Codex, or Gemini CLI sessions — self-healing, shared kanban board, web dashboard, native iOS app. Single Python file, zero external dependencies. The essential complement to any terminal-based coding agent.

github.com/mixpeek/amux · amux.io

Aider — The original open-source coding agent

Aider pioneered the terminal-based AI coding agent pattern and remains the most flexible. Works with any LLM via litellm — Claude, GPT-4, Gemini, or local models via Ollama. Every change is auto-committed with a descriptive message. Git-first design with architect/editor mode for complex changes. The best choice when model flexibility or full openness is the priority.

Strength: Model agnostic, excellent git integration, large community, well-documented. github.com/Aider-AI/aider

Cline / Roo Code — VS Code AI agent

Open-source VS Code extension that gives Claude/GPT-4/Gemini agent capabilities inside the editor — file reads, shell commands, browser control. Roo Code is a community fork with additional features and more permissive auto-approval defaults. Both have large communities and active development.

Strength: Deep VS Code integration, multi-provider, human-in-the-loop checkpoints. amux vs Cline →

OpenHands (formerly OpenDevin)

The most fully autonomous open-source coding agent. Runs in a Docker sandbox with its own browser, shell, and filesystem. Can complete end-to-end tasks including web research. Strong for tasks requiring internet access or GUI interaction.

Strength: Browser sandbox, autonomous end-to-end, active research community. amux vs OpenHands →

Continue.dev — IDE completion and chat

Open-source AI code completion and chat for VS Code and JetBrains. Not an autonomous agent — an interactive assistant. Supports 50+ model providers including local models. Highly customizable context providers and slash commands. The open-source alternative to GitHub Copilot for inline completion.

Strength: Provider flexibility, JetBrains support, customizable context, strong local model support. github.com/continuedev/continue

Goose (Block)

Terminal-based AI coding agent from Block (formerly Square). Written in Rust for performance. Extension-based architecture with toolkits for different use cases. Supports Claude, GPT-4, and local models. Younger project but growing quickly.

Strength: Rust performance, extensible toolkit architecture, Block's engineering pedigree. amux vs Goose →

Antigravity CLI (agy)

Google's open-source terminal coding agent, renamed from Gemini CLI in June 2026. Powered by Gemini 2.5 Pro, supports 1M token context windows. Fast Go implementation. Can be run via amux for parallel fleet operations.

Strength: 1M token context, fast CLI, free tier via Google AI Studio. amux vs agy →

See also: Best AI Agent Orchestrators → or all head-to-head comparisons →