{
  "height": 36,
  "block_hash": "dc301ccd2bc773dcb2e042e116a2938de9d1412a2cd5a5a262aa1d12f17642d2",
  "status": "confirmed",
  "bitcoin_block_height": 974874,
  "digest": {
    "alg": "sha256",
    "hex": "dc301ccd2bc773dcb2e042e116a2938de9d1412a2cd5a5a262aa1d12f17642d2",
    "preimage": "block:{\"at\":\"2026-11-07T00:39:14.357Z\",\"entry_count\":2,\"first_seq\":112,\"height\":36,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":113,\"merkle_root\":\"62dad6987a7450a68d4c0cd73babe30b75aaa5c4931cf97873c4b35731fe93ba\",\"prev_hash\":\"8218997b11538e6c0a6190fcebe9aa33e85b63dceda0725a7c5c4bb72cb4d485\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T00:48:43.456Z",
      "updated_at": "2026-11-07T02:48:43.467Z",
      "bitcoin_block_height": 974874,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee756c5d386970af005514bc435a3f36ab9d7e02ccf2d9765d2ff817c31276850de5749b91515c20eb628d"
        },
        {
          "type": "bitcoin",
          "block_height": 974874,
          "merkle_root": "fa522f272a37cb03554d5be30f11a1564362627a0d248c198befb5a303c3a302"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T00:48:43.456Z",
      "updated_at": "2026-11-07T03:48:43.477Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee756c2e6e94346d10681cbc2c11f3c7672bb63114f3ea81c8647fbde9327c49b6cba952953ba9230a7cfd"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "confirmed",
      "submitted_at": "2026-11-07T00:48:43.456Z",
      "updated_at": "2026-11-07T03:48:43.477Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee756c6aeb059a9fa983fece4caad3ee3387cd52f2162193b362db6411d33aa61d93da92facac3bc39f87c"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/36/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."
}