Evidence bundles

An evidence bundle is the record’s full proof package — everything a report PDF has, plus the machine-readable data and chain-verification result behind it.

What it is

The bundle is a ZIP built on demand from any sealed record: record.json (the finalized record exactly as stored), canonical.json (the canonical form its hash is actually computed over), chain.json (its chain links, plus a chain-verification result computed fresh at the moment you export — not a cached figure), every photo, and manifest.json (a SHA-256 of every file in the bundle, and bundle metadata). It’s returned as a short-lived signed URL, and the export itself is written to your audit log.

Before you start

Exporting a bundle needs evidence permission at Export level or above.

How to do it

1. Open the sealed record in Evidence.
2. Click Evidence bundle to build and download the ZIP.
3. Use the signed download link promptly — it stays valid for a short window and is never trusted or re-rendered directly by anything else.
4. Hand the whole ZIP to whoever needs to independently verify the record — a regulator, a solicitor, or your own compliance team — rather than extracting individual files, so the chain-verification result travels with the record it describes.

How it integrates

The chain is re-verified at the exact moment of export, not read from a cached flag, so chain.json’s result is as current as the export itself. This never alters or removes the underlying evidence — a bundle is a read-only copy. Unlike the plain report PDF (see The report), a bundle is built for independent, offline verification rather than for reading — canonical.json is exactly the byte sequence the hash was computed over, so a third party with no HousingSurvey Pro access can recompute the hash themselves and confirm it matches.

Common problems

• The download link has expired. Signed URLs are deliberately short-lived — go back to the record and export the bundle again for a fresh one.
• I need this for more than one record at once. Bundles are exported one sealed record at a time; for bulk data across many records, see Exporting data: which export do I want?.
• The export control is greyed out. It needs evidence permission at Export level, a higher bar than simply viewing the record.