{
  "height": 35,
  "block_hash": "8218997b11538e6c0a6190fcebe9aa33e85b63dceda0725a7c5c4bb72cb4d485",
  "status": "confirmed",
  "bitcoin_block_height": 974874,
  "digest": {
    "alg": "sha256",
    "hex": "8218997b11538e6c0a6190fcebe9aa33e85b63dceda0725a7c5c4bb72cb4d485",
    "preimage": "block:{\"at\":\"2026-11-07T00:36:44.349Z\",\"entry_count\":1,\"first_seq\":111,\"height\":35,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":111,\"merkle_root\":\"87bb775be8f440b8edd810f8b73958944def3e6431c8f46f78f920a1d7dcc499\",\"prev_hash\":\"acf7be36eb472b60c9705b2b3af5d8e9c99c5729dc055b665a10c7124003e5b1\",\"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": "6aee731767a2f9beee0616f47d19e297028d13724ec9ba0ac3c019253a33f22a9913ce02455d3d57b313791e"
        },
        {
          "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": "6aee73171e9f8c08ee019ac9cae0e6b0b53f20ae24912791f3633441aeb27bbe0776d1e126b1a0c16c6890c8"
        },
        {
          "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": "6aee7317d8b78b90fc79e6ea95348b3812308b656a0df4663d0f0f6a2b0b21b4c3cb888540abe6e20a21c5a3"
        },
        {
          "type": "bitcoin",
          "block_height": 974877,
          "merkle_root": "dee625f48434576e86df10e80f2912b1c31b96672232e47e103806c1faef5814"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/35/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."
}