{
  "height": 33,
  "block_hash": "4ff56e77792954e2401fd845f4988dabfe50079546d4bfda0893a1bcab2c3dd5",
  "status": "confirmed",
  "bitcoin_block_height": 974874,
  "digest": {
    "alg": "sha256",
    "hex": "4ff56e77792954e2401fd845f4988dabfe50079546d4bfda0893a1bcab2c3dd5",
    "preimage": "block:{\"at\":\"2026-11-07T00:32:14.330Z\",\"entry_count\":1,\"first_seq\":108,\"height\":33,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":108,\"merkle_root\":\"061828d5a063c0df8a9aa2e5e488289e7e1a8722bb83716c3055eb09153983c4\",\"prev_hash\":\"c701a4a9f561a0a2c8782a7a62692bf58793d33ecd4eacb9739a0ee07297bed1\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T00:38:43.455Z",
      "updated_at": "2026-11-07T02:38:43.467Z",
      "bitcoin_block_height": 974874,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee7315c5b460b8c4129b4c40db48c2a0e306297d6812b6276e6ee7c651dc95edc89253c1f1738c803d57c7"
        },
        {
          "type": "bitcoin",
          "block_height": 974874,
          "merkle_root": "fa522f272a37cb03554d5be30f11a1564362627a0d248c198befb5a303c3a302"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T00:38:43.455Z",
      "updated_at": "2026-11-07T03:38:43.477Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee7315342eeaa2632834cde1d87d662b69c6d640237753b47c210a062013f4427d8ecfadf05b54adf2b2a4"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "confirmed",
      "submitted_at": "2026-11-07T00:38:43.455Z",
      "updated_at": "2026-11-07T03:38:43.477Z",
      "bitcoin_block_height": 974877,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee7315951ca5990c7764e0af376c59dc8fbf1caa1faec9b81f2a8622755c3ddfa2ece832a8dfd927497001"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/33/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."
}