{
  "height": 58,
  "block_hash": "7a8203b97bd804615522c5e71cb6be89fef5322344e2ca88c5497372615b0bf9",
  "status": "confirmed",
  "bitcoin_block_height": 974877,
  "digest": {
    "alg": "sha256",
    "hex": "7a8203b97bd804615522c5e71cb6be89fef5322344e2ca88c5497372615b0bf9",
    "preimage": "block:{\"at\":\"2026-11-07T01:30:45.111Z\",\"entry_count\":1,\"first_seq\":146,\"height\":58,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":146,\"merkle_root\":\"5db884290b02aa0b90979dda4c382237d7abd1aefe8c58cf45fcfb332e129499\",\"prev_hash\":\"bf61797fbf9f9c252933cd56bdbb3a6988158482ebfa30386bdd53760d690014\",\"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": "6aee81257d8190eff9300066573453526e68024341289b2b8d6be137ebc324e7f70ee9ccd3ee10021d1ced55"
        },
        {
          "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": "6aee8125b534713cf8c800b65c5ff0a9b494f9f1f3ed748f545301ae53d03a21ef3e470b5c267fced92553f6"
        },
        {
          "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": "6aee8125c48692a9c361f6051badfcc0e800ea3e2ea7b827894a1ff8b1d57198e69c773095253b992237e835"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/58/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."
}