Comparison
Relay vs Devin
Devin is a hosted autonomous engineer that supplies the model and the machine. Relay is a harness you install that supplies neither. The real question is not which is smarter — it is whether you want the loop on your infrastructure and your provider account.
Facts checked against official docs on 2026-09-08
What Devin is
Devin is Cognition’s autonomous software engineer: an agent that plans, writes, tests and ships code in its own cloud VMs, reached from a web app, an embedded IDE, Slack and Teams, and an API. It is now an umbrella brand rather than one surface — Devin Desktop launched on 2026-06-02 as "the next generation of Windsurf", there is a local Devin CLI installed with a one-line curl script, and Devin Review is a separate code-review product. Cognition also trains its own models: SWE-1.7, announced 2026-07-08, is served through Cerebras, and Devin Fusion routes between a frontier model and a cheaper one mid-session.
Pricing: Free $0 · Pro $20/mo · Max $200/mo · Teams $80/mo for the team plus $40/mo per full dev seat, with free flex seats · Enterprise custom, billed in Agent Compute Units at a rate set in the order form. Model usage is included in the price. The widely republished "$500/mo for 250 ACUs at $2.25 each" lineup was retired on 2026-04-14 and is not current. As of 2026-09-08.
Side by side
| Devin | Relay | |
|---|---|---|
| Who supplies the model | Cognition. Devin fronts models from OpenAI, Anthropic, Google, xAI and others plus its own SWE series. Its enterprise FAQ states Devin "is a compound AI system and does not currently support third-party LLM API keys". | You do. 31 provider namespaces ship in the model registry, or attach an existing Claude, GitHub Copilot or ChatGPT subscription by OAuth. Relay never sits in the inference path. |
| Where inference runs | Cognition’s cloud, always. The two enterprise deployment models both list the "brain" as Cognition Cloud; Outposts moves execution, file edits and repository access onto your machines over an outbound-only connection, but not the model call. | Wherever your provider is. Relay runs on the developer’s machine and calls the endpoint your key points at. |
| Runs on your own machine | Yes — the Devin CLI is a local terminal agent working with local files, installed by one-line curl, Homebrew or a Windows binary, and it runs over ACP inside JetBrains, Zed and Xcode. | Yes — this is the only mode. There is no Relay-hosted runner to fall back to. |
| What ends an unattended run | Documented task envelope is roughly three hours of human work; larger jobs are split across parallel managed sessions by a coordinator, with Dynamic Workflows for deterministic steps. | A budget you declare: turns, tokens, wall-clock milliseconds, and retries per gate — plus completion gates that are your own shell commands, which must exit zero before the run may end. |
| Price shape | Seat price includes model usage; self-serve overage is billed in dollars, Enterprise in ACUs at a contracted rate. | $0 forever for a local developer, $15 per signed-in developer per month ($12 billed yearly). Inference is billed to you by your own provider and never resold. |
| Account required to start | Yes. | No. The install is keyless; sign-in is for team governance, machine visibility and CI trust. |
Where Devin is the better tool
- Parallel fan-out. A coordinator session can split a large job across managed Devin sessions each in its own VM. Relay has no equivalent — concurrency is however many agents your laptop can hold.
- Work that outlives the machine, not just the terminal. Relay’s sessions survive a closed terminal; they do not survive a closed laptop. Devin’s cloud sessions do.
- People who are not in a terminal. A web app, a full IDE, Slack and Teams, scheduled sessions and an API. Relay is a terminal program.
- One invoice. Devin’s price includes inference; Relay’s $15 explicitly does not, and every developer must hold and rotate a provider key.
- Enterprise procurement: SSO, teamspace isolation, spend caps, security profiles, and code review as a shipped product surface.
- A clean environment the agent did not inherit — a cloud session comes with a terminal, an IDE and a browser already wired up, so the agent can open the page it just changed.
The honest take
Two framings that a Relay-authored comparison reaches for first are both false, and they are worth naming because they are everywhere in third-party listicles. "Devin is cloud-only" is wrong — there is a local CLI installed exactly the way Relay’s is, and Outposts runs execution on customer machines. "Devin does not verify its own work" is wrong too: Cognition documents Devin running tests in its own environment and iterating until they pass. What survives verification is narrower and more useful. Devin decides which model you get and keeps the inference in its cloud; Relay makes both of those your decision, and that is the whole trade. If you want an autonomous engineer that arrives complete — machine, model, review surface, invoice — Devin is built for exactly that and Relay is not trying to be. If the model choice, the provider bill, and the machine the loop runs on need to stay yours, that is the case for a harness.
Sources
- https://devin.ai/pricing
- https://docs.devin.ai/get-started/devin-intro
- https://docs.devin.ai/enterprise/deployment/overview
- https://docs.devin.ai/cloud/outposts/overview
- https://docs.devin.ai/work-with-devin/devin-cli
- https://cognition.com/blog/new-self-serve-plans-for-devin
Run the harness yourself — one command, your own model key, no account: curl -fsSL https://relayevals.com/harness/install.sh | bash. Quickstart · What is a coding agent harness? · Pricing