How it works
A Service Book is a tamper-evident logbook keyed to a vehicle’s registration. Here is exactly why you can trust one — no crypto-mysticism required.
Stamps, not edits
Every service record is a stamp: what was done, the parts used, the mileage, the date, and who did the work. Once issued, a stamp is immutable — nobody can edit or delete it, not the workshop, not the owner, not even us. Made a mistake? A correction is appended underneath with its own timestamp; the original stays visible. That’s how paper stamps worked, minus the losing-the-book part.
The hash chain
Each stamp is run through SHA-256 — a mathematical fingerprint function — together with the fingerprint of the previous stamp. Change a single character in any old record and every fingerprint after it stops matching. The first stamp chains from the book’s own genesis, so a chain can’t be transplanted between vehicles either.
Plain-English version: the history is a paper chain where every link is glued to the one before it. You can add links to the end; you cannot swap one out of the middle without the whole thing falling apart in an obvious way.
Trust tiers
Tamper-evidence proves a record hasn’t changed — it doesn’t prove it was true when written. So every stamp carries its provenance on its face:
Issued by a workshop that passed our verification (Companies House, VAT, premises evidence). The workshop’s name and address at the time of issue are frozen into the stamp — surviving renames and rebrands.
Recorded by the keeper. Still hash-chained and immutable, but it’s the owner’s word — and it’s labelled as exactly that.
Carried over from a paper service book with supporting evidence. Useful context, honestly labelled.
The public verifier
Any stamp can be checked by anyone, free, forever. The verifier re-computes the vehicle’s entire chain from scratch and tells you whether the stamp’s fingerprint — and every link before it — still holds. If a seller shows you a Service Book, you don’t have to take their word for it: tap any stamp and watch the maths check out.
Sharing by QR
Owners share their history with a QR code or link — scannable by any camera app, no account needed. Links are scoped (full history, or just a summary), revocable at any time, and can carry an expiry date or a view limit. Selling the bike? Print the QR and stick it on the tank. Done with the listing? Revoke the link and the page goes dark at once, along with any documents on it. Individual stamps stay verifiable through their own QR — that permanence is the point of a stamp.
Plate lookups on the other hand only ever show a privacy-safe summary — never keeper identity, never the full timeline.