Mstro vs Devin
Mstro vs Devin: Cognition's autonomous software engineer
Devin is a closed, cloud-hosted AI engineer. Mstro is an open tool that runs on your machines with your code and your API key.
Summary
Devin from Cognition runs in their cloud sandbox. You submit a task, it works, you review the result. It's impressive for long-horizon autonomous work but has limited local integration. Mstro is the opposite architecture: your code stays on your machines, the agents run locally under the Security Bouncer, and you drive everything from your browser. Same "walk-away" experience, different trust model.
Feature-by-feature
| Feature | Mstro | Devin |
|---|---|---|
| Execution location | Your machines | Cognition cloud sandbox |
| Code privacy | Never leaves your hardware | Runs in their environment |
| Parallel agents on git worktrees | PM Board | Session-based |
| Browser IDE | Full editor + terminal + git | Chat-style interface |
| Pricing | Free for first 1,000 users + BYOK | Per-seat subscription |
When Devin wins
- You want a fully-managed, nothing-to-install experience
- You're OK sharing code with a third-party sandbox
- You want the specific Devin UX and are on their plan
When Mstro wins
- Your code cannot leave your machines for IP, compliance, or trust reasons
- You want to run agents on your existing dev VMs, laptops, or servers
- You want a browser IDE with full file explorer, terminal, and git
- You want parallel agents on separate git worktrees, not a single sandbox session
- You prefer BYOK pricing over a per-seat platform fee
Our take
Devin is closer to a contractor — you brief it, it does the work in their environment, you accept the PR. Mstro is closer to a workstation — your machines, your code, your agents, driven from your browser. Pick based on your trust and deployment model.
Try Mstro
Free for the first 1,000 users. No credit card. Bring your own Anthropic API key.