{
  "height": 77,
  "block_hash": "ecf7c240b9edfc8f546f3da1cbc20d957b0fcf4e5242f030066277fdde340043",
  "status": "confirmed",
  "bitcoin_block_height": 974880,
  "digest": {
    "alg": "sha256",
    "hex": "ecf7c240b9edfc8f546f3da1cbc20d957b0fcf4e5242f030066277fdde340043",
    "preimage": "block:{\"at\":\"2026-11-07T02:17:15.255Z\",\"entry_count\":1,\"first_seq\":174,\"height\":77,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":174,\"merkle_root\":\"9770a5af2f8fc4d2c8c62fe5c2456f2f3fb3a1186a2178f8787b37f831c2867a\",\"prev_hash\":\"4c7e982cc8aa6aa5ecc866354e009f23e8d9de8b880e9b9680d6e54dbbd2380b\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:18:43.465Z",
      "updated_at": "2026-11-07T04:18:43.479Z",
      "bitcoin_block_height": 974880,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee8a8762fee31e9fdf1193ee4821cfb944f56ea64bcaafcaff7313294254126a7724be245149d667f5c79b"
        },
        {
          "type": "bitcoin",
          "block_height": 974880,
          "merkle_root": "e20917e92c25ba0bebbc60b5b7fe48f0ee84f05c3eb4987c3107d249f2c7113d"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:18:43.465Z",
      "updated_at": "2026-11-07T04:18:43.479Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee8a8736e5c0177308d235cb374e088237548513669beb6b246f9168217d06fa33c4cec5ff96275499e418"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T02:18:43.465Z",
      "updated_at": "2026-11-07T02:18:43.465Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee8a87133dc105dc0f9bebfe093b1aef246237d2c9f3ba722075bd9337a27b6da46822103bc7b430017c57"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/77/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."
}