Is there a fully open-source version of Devin?

OpenHands (formerly OpenDevin) is the closest open-source equivalent. It is MIT-licensed, runs in Docker, and supports multiple LLM backends. SWE-agent is another research-grade option with strong benchmark results.

Can I run a Devin alternative without Docker?

Yes. Aider and Claude Code run directly in your terminal with no container required. Codex CLI also runs locally. These tools do not provide the sandboxed Linux environment that Devin and OpenHands use, so you get more control but also more responsibility for isolation.

Devin Alternatives in 2026

Devin by Cognition is a fully managed cloud engineer that can take an issue and produce a pull request with minimal human involvement. It is impressive but it runs on Cognition's infrastructure, charges per ACU, and gives you limited visibility into what the agent is doing at each step.

If you want similar autonomous coding capability on your own infrastructure — or without the per-ACU billing — there are several serious options worth evaluating. This page covers the open-source and self-hosted alternatives that teams actually use.

OpenHands (formerly OpenDevin)

Full open-source SWE agent runtime that supports dozens of LLMs, runs in Docker, and exposes a browser-based UI for watching the agent work in a sandboxed Linux shell. Closest architectural match to Devin in the open-source space.

Best for: Teams that want Devin-style autonomy on their own servers and are comfortable managing a Docker environment.

SWE-agent

Princeton research project that defines the agent-computer interface (ACI) pattern. Strong SWE-bench results and a clean codebase that is easy to study and extend.

Best for: Researchers and engineers who want to understand or benchmark autonomous coding agent behavior.

Aider

Terminal-based pair programmer that works with any OpenAI-compatible model. Mature git integration, supports multi-file edits, and has an active community shipping weekly improvements.

Best for: Individual developers who want fast, local, agentic editing without a cloud dependency.

Claude Code

Anthropic's official CLI agent. Runs in your terminal, reads your whole codebase, and handles multi-step tasks including writing tests and opening PRs. No remote execution sandbox — it runs as you.

Best for: Teams already on Claude who want a capable CLI agent with direct filesystem and git access.

Cline

VS Code extension that gives Claude or any OpenAI-compatible model a read/write/execute loop inside your editor. Transparent tool-call UI so you can approve or reject each action.

Best for: Developers who prefer staying inside VS Code and want granular approval control over agent actions.

Codex CLI

OpenAI's open-source terminal agent. Sandboxed execution, multimodal input, and a straightforward approval workflow. Designed to be auditable and composable.

Best for: Teams on the OpenAI stack who want a self-hosted terminal agent with a safety-first design.

Where Fleet fits

Fleet does not write code itself. It first jails Fleet-launched Linux agents. A grant names a host for a bounded window; prove it at /security#containment. Then it orchestrates Claude Code or OpenCode across repos with budgets, approvals, and an audit trail. Devin's cloud sandbox is a vendor VM. If you want Devin-style autonomy at team scale without cloud lock-in, Fleet plus your coding harness is the self-hosted answer.

How to choose

Pick Devin if you want a fully managed cloud engineer and per-ACU billing is acceptable.

Pick OpenHands if you want the most Devin-like open-source experience with Docker self-hosting.

Pick Aider if you are a solo developer and want the fastest terminal-based workflow.

Pick Claude Code if your team already uses Claude and wants a capable CLI agent.

Pick Fleet if you need a jail around locally running agents plus orchestration across repos.