// The proof pipeline
Capture, hash,
anchor, verify.
Every event that passes through Attesto becomes a cryptographic proof object. Here is how the six-step pipeline works — from raw event to independently verifiable receipt.
Capture
A system event occurs and is submitted to Attesto via SDK, API, connector, or batch import. The event data is received and prepared for processing.
Canonicalise
The event is normalised into a stable, deterministic structure. The same event always produces the same canonical form, ensuring consistent verification later.
Hash
A cryptographic fingerprint is computed from the canonical form using SHA-256. Any later modification to the event produces a completely different hash.
Merkle aggregate
Large volumes of event hashes are aggregated into a Merkle tree. This allows efficient proof generation for any individual event within a batch.
Anchor
The Merkle root is anchored to an external reference point, creating a time-stamped commitment independent of Attesto's own infrastructure.
Verify
Any event can be verified by independently checking its hash, Merkle path, and anchor reference. Verification requires no access to the original system or raw data.
// Why Merkle trees
Attesto does not need to know your data to prove your data.
Raw data can remain inside your environment, encrypted storage, or EU data region. Attesto records cryptographic fingerprints and proof paths. Organisations can prove integrity without exposing sensitive content.
// Independent witnesses
Evidence is witnessed by independent parties.
Attesto supports four witness types: Attesto-operated, customer-operated (Local Vault), assurance witnesses, and partner witnesses. Quorum policies define how many witnesses must attest before a checkpoint is confirmed.
Attesto-operated
Default witness operated by Attesto, providing baseline independent attestation for every evidence stream.
Customer-operated
Deploy Local Vault in your own infrastructure. Your environment independently witnesses evidence — separate from Attesto's servers.
Assurance witnesses
Third-party assurance organisations participate as witnesses for regulatory or audit-specific evidence streams.
Partner witnesses
Ecosystem partners serve as witnesses, extending independent attestation for specific use cases and industries.
// Portable verification
Evidence that travels without the backend.
Proofstream bundles package receipts, checkpoints, witness statements, and anchors into a portable Truth Package. Auditors verify evidence offline using the Attesto CLI — no backend access needed.