Devin writes the code.
Hyrax architects above it.
Devin from Cognition takes a ticket and works it autonomously in its own environment, which is genuinely useful for well-scoped tasks. Hyrax is the layer above the agents: it decides what work is worth doing and whether the result fits the system.
- Hyrax audits roughly 400 of its own repositories.
- Free plan: full access, up to 100 PR reviews a month, a $30 starter credit, and $10/month ongoing.
Verified end to end, with no Devin handoff
What changes when Hyrax runs above the tools.
Judgment above the agents
Devin executes the task it is given. Hyrax decides what is worth doing and whether the result fits the system it lands in.
Verified before review
Every change runs the project baseline tests, build and lint, and passes a second reviewer agent, before the pull request exists.
Context that compounds
The map of the codebase lives in the repository and strengthens with every merge, so the next decision starts from everything learned before it.
One ticket at a time, or the codebase as a whole.
| Decision criteria | Devin | Hyrax |
|---|---|---|
| Unit of work | The assigned ticket, worked in a cloud workspace. | The whole repository, audited continuously across six domains. |
| Codebase context | Builds understanding per session, with a wiki over the repository. | A durable map committed to the repository as HYRAX.md and .hyrax/discovery, so it strengthens as the codebase changes. |
| Output type | Pull requests produced by autonomous sessions. | Verified pull requests, plus issues ranked by severity and effort. |
| Verification | Runs tests in its own workspace, and repository CI gates the pull request. | Baseline tests, build, lint and a second reviewer agent run against the project itself before a pull request opens. |
| Human control | The team reviews sessions and merges. | A human approves and merges every pull request. Hyrax never merges on its own. |
| Delivery surface | Slack, the Devin web app and GitHub. | GitHub pull requests, with issues and posture in the Hyrax console. |
| Pricing model | Usage based on compute credits, starting around $20 per month. | Free plan with a $30 starter credit and $10/month ongoing. Paid is $30 per user per month and each paid user gets $30/month of credits. |
Read how Devin describes itself: devin.ai(opens in a new tab)
Comments on a diff, or a verified pull request.
- 01A developer assigns Devin a task.
- 02Devin writes code for that task and stops when the task is done.
- 03The team decides whether the change fits the wider system, then merges.
- 01Maps the codebase and keeps the map in the repository
- 02Applies architectural judgment across six domains
- 03Opens a verified pull request that a human merges
GitHub-native. Human-controlled. Verified before merge. No training on customer code.
From install to the first verified pull request.
Install the GitHub App
Grant read access to the repositories in scope. No card is required to start.
Hyrax maps the repository
Discovery writes HYRAX.md and .hyrax/discovery into the repository, so humans and AI tools read the same context.
Review the first pull request
Approved upgrades arrive as verified pull requests. A human merges every one.
Both tools solve real problems.
Choose Devin if
There is a backlog of well-specified tickets and the team wants an agent to work them end to end. Devin is built for delegated execution of that kind.
Choose Hyrax if
The harder question is which work matters and whether the result belongs in the system. Hyrax audits six domains, ranks issues, and verifies every change against the project itself.
Usage based compute credits, with team plans above it.
Free plan with a $30 starter credit and $10/month ongoing. Paid is $30 per user per month, and each paid user gets $30/month of credits.
Questions about Devin and Hyrax.
Does Hyrax work alongside Devin?
Yes, and most teams run both. Devin keeps doing its job. Hyrax works at the level of the whole codebase, decides what is worth changing, and delivers verified pull requests. Nothing about the Devin setup has to change.
What does Hyrax change in the repository?
Discovery writes HYRAX.md and a .hyrax/discovery directory, which document the architecture, conventions and risk areas of the codebase. Everything else arrives as a normal pull request on its own branch. Hyrax has no write access to the default branch.
How does pricing work?
The free plan includes full access, a $30 starter credit and $10/month of credits ongoing, with no card required. The paid plan is $30 per user per month, and each paid user gets $30/month of credits. Pull request reviews are included on every plan.
What happens after signup?
Installing the GitHub App and granting access to a repository takes a few minutes. Hyrax maps the codebase, then runs the first audit and returns issues ranked by severity and effort. The first verified pull requests follow once an audit is approved.