STEINLOG
ENPLDEAR
Become a design partner

02 · Trust spine

Every line, accountable.

A bid isn’t just documents — it’s a record of who decided what, from which source, and when. Steinlog makes that record walkable, tamper-evident, and — at submission — legally probative. The difference: the record is yours, the bidder’s, not the buyer’s.

A
Daily trustClick any number, clause, or PDF and walk its origin — the human who set it, the source it cites, the version it supersedes.
B
Continuous integrityEvery change is hash-chained, content-addressed, and attributed to a human or a named AI model. The runtime can’t rewrite history without it showing.
C
Episodic proofAt submission the package is sealed with an eIDAS qualified timestamp and your signature — and we ingest the portal receipt back. One click yields a defense pack for a protest or an antitrust challenge.
Walk any line to its origin
BOQ 1.2 · Foundations · € 4 200
↳set by — human · estimator · 2026·06·20 14:02
↳source — SWZ §7.2, page 14 · cited
↳supersedes — v2 · € 4 050 · AI draft
↳sealed in — ASiC-E manifest · LV-2026/0247

The package you leave with

✓ASiC-E · manifest sealed
✓QTSP · qualified timestamp
✓Portal receipt · ingested
One click → a defense pack

For a protest, a KIO / VK-Bund appeal, or an antitrust challenge: who priced what, from which source, sealed and receipted.

Honest by design: the log is tamper-evident, not tamper-proof. The legally-probative claim attaches to the signed, timestamped, receipted package — the artifact you can hand a tribunal.

Build the first provable bid with us.

We’re onboarding a handful of Polish and German construction firms as design partners. Bring a live tender; we’ll build the loop around it.

Become a design partner
  • EU-hosted, end to end
  • No model training on your data
  • eIDAS-ready — AdES default, QES on demand
  • No sales call to start