Nineteen Guardians keep Wormhole running. They watch the chains, sign what they see, and gossip those signatures until thirteen agree, and a VAA is born. But how well is each Guardian really doing? Who signed late? Who missed a message? Answering that fairly takes an independent record that anyone can check. That’s the Guardian probe.
A probe joins the Guardians’ gossip network as an ordinary peer. It publishes nothing. It just listens, recording every message on every topic: observations, VAAs, heartbeats, governor updates, along with when it arrived, and who signed it. Two of the probes also read the chains directly, through two independent providers, to check what Guardians report against what actually happened.
One listener isn’t enough. A problem in one region can be invisible from another. So there are six: in Singapore, Finland, Frankfurt, London, São Paulo, and Virginia. Each runs on a small, locked-down cloud machine, with the same immutable image, built from a tagged release with SLSA level three provenance, and scanned for vulnerabilities. Updates reach a canary first, then the fleet.
Everything they record becomes layer one: the raw evidence. Each message is written to a local log first, so nothing is lost silently. Every five minutes, the window is sealed into Parquet files, one per stream, and uploaded to a public bucket, kept for a year. Anyone can download them, query them, and rebuild the analysis. Even the probe’s own gaps and clock drift are recorded.
But what stops anyone, even the Foundation, from quietly changing those files later? Every hour, each probe writes a manifest: every file it uploaded, with a SHA-256 fingerprint of its exact bytes. It signs the manifest with its own key, gets an independent timestamp, and records it in Rekor: Sigstore’s public, append-only transparency log, which the Foundation doesn’t run. And each manifest points to the one before it, forming an unbroken chain. Change one byte, drop a file, or rewrite an hour, and the fingerprints no longer match a record that’s already public. Anyone can check, with just the files, the probe’s public key, and the log.
Six listeners. Public evidence. Proof it hasn’t changed. The Guardian probe: an independent record of the Guardian network that anyone can verify.
Music: “Technology Modern Electronic” by Grand_Project (Pixabay).