Getting started

A node is one small program that signs and stores events. You keep the key and the data. Linux only: see Install on Linux first.

Every command on this page was run on fresh Ubuntu 24.04.5 and Rocky Linux 10.2 servers (5 November 2026): create a node, record an AI decision, evidence and a council step, verify all three ledgers, serve them over HTTP, and cross-sign a checkpoint with a witness. See what was tested.

The node is a free proprietary binary (source not published). Get it from Install on Linux, then follow these steps.

1. Create a node

entropa-platinum init ./node

This creates a private signing key (platinum.key, mode 0600) and the ledger directory. Back up the directory; never share the key file.

2. Record an event

echo '{"label":"nl_query","decision":"allow","reason":"guard_passed",
 "input":"How many claims were denied by payer?",
 "output":"SELECT payer_id FROM platinum_denials_by_payer LIMIT 10",
 "run_id":"run-1","provider":"vertex","model_id":"gemini-3.8-flash",
 "input_tokens":120,"output_tokens":40,"cost_micro_usd":90}' \
 | entropa-platinum log ./node

The node hashes the question and the answer, drops the text, signs the event, appends it and signs a new checkpoint. The reply carries the event hash, the new ledger size and the Merkle root.

3. Verify

entropa-platinum verify ./node          # prints: OK records=1 checkpoints=1

4. Record audit evidence too

echo '{"kind":"evidence.pipeline_run","label":"silver","decision":"allow",
 "reason":"check_passed","control":"hipaa_164_312_c1",
 "total":7000,"passed":6210,"flagged":790,
 "detail":"night=2026-11-05 layer=silver","run_id":"run-2026-11-05-s"}' \
 | entropa-platinum log-evidence ./node
entropa-platinum verify-evidence ./node

Evidence goes to a separate ledger beside the AI decisions. See Controls evidence.

5. Serve it over HTTP

PORT=8080 entropa-platinum serve ./node

Now any language can post events. See Run a node for the endpoints.