What is Devin?
Optional reading: go deeper
Meet Devin: an autonomous software engineer that runs in the cloud. It gets its own machine, its own browser, and its own terminal, and it works the way a human engineer does. It reads your codebase, makes a plan, writes code, runs tests, and opens a pull request.
The most useful mental model is to treat Devin like another member of your engineering team. A capable engineer can take a well-written ticket and run with it, but they do better with clear specs, they need access to the right repos and credentials, and you still review their PRs. Everything in this course flows from that model: how you would onboard, instruct, and review a new teammate is how you will get the most out of Devin.
How Devin compares to other AI tools
The AI tools you have used so far sit on a spectrum of how much you stay in the loop:
| Category | Examples | Who is doing the work |
|---|---|---|
| Autocomplete and copilots | inline code suggestions | You are. They suggest code while you type. |
| Agentic IDEs and local agents | Devin Desktop, Devin CLI, Cursor, Claude Code | You supervise in real time while they execute on your machine. |
| Cloud agents | Devin | You delegate, walk away, and come back to a PR. |
Unlike a local agent, which runs in your editor and on your filesystem under your attention, Devin runs remotely in a fresh cloud VM with its own operating system, filesystem, terminal, and browser, set up with your repository and dependencies. It can install packages, run builds and long test suites, and break things without touching your laptop or local branch, avoiding works-on-my-machine drift while leaving your machine free. Each session gets its own VM, so you can run several sessions at once.
From single-threaded to multi-threaded
This is the shift worth internalizing. With autocomplete and local agents, you are single-threaded: you are the person typing every line, and progress is capped by your own keystrokes. When you can delegate well-scoped work to cloud agents and run several in parallel, engineering becomes multi-threaded. You stop being the person typing every line and become the person directing a team.
Key takeaways
- Devin is an autonomous cloud engineer with its own machine, browser, and terminal that reads code, plans, codes, tests, and opens PRs.
- Treat it like a teammate: give it access, clear specs, and review its PRs.
- Autocomplete suggests, local agents execute under your supervision, and cloud agents run autonomously while you do other work.
- Delegating to parallel agents moves you from single-threaded to multi-threaded engineering.