Questions a reviewer asks first.

Which pull requests can I check?

Public GitHub pull requests of Node.js projects. Noether installs the repository's dependencies with npm in a Node 24 sandbox and runs checks with node --test. A private repository is refused, and a project without a package.json cannot be run.

How long does a run take, and what does it cost me?

About a minute for a small pull request. A run is stopped after 270 seconds. It is free; to keep the cost bounded, one address may start 3 live runs per hour and the service accepts a fixed number per day. The replay of the sealed Hopper run is a real earlier run and never counts against that.

What do the verdicts mean?

• BROKEN: a behaviour that held on the base commit fails on the head, and the pull request does not announce the change.
• CONSERVED: every pinned behaviour still holds on the head.
• INCONCLUSIVE: nothing could be pinned, or the run could not finish. The reason is always given and nothing is claimed.

Can a CONSERVED verdict be wrong?

Yes. Only behaviours that were pinned, and green twice on the base, are compared, and a language model writes the checks. A break nobody pinned stays invisible, and two runs of the same pull request can pin different checks. The benchmark lists the catches, the misses and the false alarms.

What is a seal, and how do I check one?

Each finished run is stored as one JSON bundle with its sha256. Every run page re-hashes the bundle in your browser and compares it with the recorded hash. Download the JSON from the same page to hash it yourself.

Who sees my code?

For a live run, GitHub, Nebius (models and sandbox) and the server that hosts the site. The privacy page lists each one and what it receives.

Can I run it on my own repository?

Yes, as a GitHub Action with two Nebius secrets. The Action page has the workflow file, every input and output, and when it fails a job.