{
  "height": 60,
  "block_hash": "290ad3de1a469069af4c0556708b5eeb2605fb89b2c2a3ae2950f406ab8bbb26",
  "status": "confirmed",
  "bitcoin_block_height": 974877,
  "digest": {
    "alg": "sha256",
    "hex": "290ad3de1a469069af4c0556708b5eeb2605fb89b2c2a3ae2950f406ab8bbb26",
    "preimage": "block:{\"at\":\"2026-11-07T01:35:45.133Z\",\"entry_count\":1,\"first_seq\":149,\"height\":60,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":149,\"merkle_root\":\"c366f601b7861e488fd34275b0fb4d312a54cece38a5832108cf14017030af00\",\"prev_hash\":\"6dc1f3ccffb923232d39277c532c6888f4c65467f1c61d0b9c1f86f693edd1b3\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:38:43.460Z",
      "updated_at": "2026-11-07T04:38:43.483Z",
      "bitcoin_block_height": 974880,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee8127f2f773a8afbccf8b463751894476b74a7a7ee4fdb368d89e506e87742555c97eea9979330a6a8ea5"
        },
        {
          "type": "bitcoin",
          "block_height": 974880,
          "merkle_root": "e20917e92c25ba0bebbc60b5b7fe48f0ee84f05c3eb4987c3107d249f2c7113d"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:38:43.460Z",
      "updated_at": "2026-11-07T04:38:43.483Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee8127730e436716435b4456c9d519e11ea336cc067c7c67672cb8c88c2b54784d5e459c202562691057e9"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "confirmed",
      "submitted_at": "2026-11-07T01:38:43.460Z",
      "updated_at": "2026-11-07T03:38:43.477Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee81271a9ffea43834be0e0afd1f9c32b6767be55e1638a7f9bc45b519eedf7f504558d0cdd4eed2549d4a"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/60/anchor.ots",
  "how_to_verify": "Download the .ots proof and run `ots verify -d <block_hash> <file>.ots` with the OpenTimestamps client, which checks the Bitcoin attestation against Bitcoin block headers. The digest is the block hash: sha256 of digest.preimage, the text \"block:\" followed by the canonical block header, which is the same header the issuer signs."
}