{
  "height": 8,
  "block_hash": "8572da23d5439400df806a3016eb2cd5f80121dc739c0c9c694af4e56e9c473d",
  "status": "confirmed",
  "bitcoin_block_height": 974874,
  "digest": {
    "alg": "sha256",
    "hex": "8572da23d5439400df806a3016eb2cd5f80121dc739c0c9c694af4e56e9c473d",
    "preimage": "block:{\"at\":\"2026-11-06T22:45:18.495Z\",\"entry_count\":2,\"first_seq\":60,\"height\":8,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":61,\"merkle_root\":\"af6a337062372956e5ef196648582cce259ddc47d1fca18a9de14aad6607e80f\",\"prev_hash\":\"9b578624c1d48775a02538294fc183ac9ccc100629db31df41627c324111f75b\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-06T22:54:47.911Z",
      "updated_at": "2026-11-07T03:08:43.475Z",
      "bitcoin_block_height": 974874,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee5ab8db099d50551aceae43b47212ef61b575d31d04eefafcf26b4e865d64456c5d64c6e7d821df7675cd"
        },
        {
          "type": "bitcoin",
          "block_height": 974874,
          "merkle_root": "fa522f272a37cb03554d5be30f11a1564362627a0d248c198befb5a303c3a302"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-06T22:54:47.911Z",
      "updated_at": "2026-11-07T03:08:43.475Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee5ab9496ee1e3e04435941a09e3eb2e303ba2e322856e74cf2e0fa836b8aa7dc1f862447eeabbb357571b"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "confirmed",
      "submitted_at": "2026-11-06T22:54:47.911Z",
      "updated_at": "2026-11-07T03:08:43.475Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee5ab98105bc0ec2314697b8c471afa4a150dfc6c8ad572bc5199f4705dd9f63a13a3c312d2b6dd15008f7"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/8/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."
}