{
  "height": 90,
  "block_hash": "ed1cee41c6396294da6fd23a7cb889928142f21d56c5ed7fd2a70aaad95571fa",
  "status": "confirmed",
  "bitcoin_block_height": 974883,
  "digest": {
    "alg": "sha256",
    "hex": "ed1cee41c6396294da6fd23a7cb889928142f21d56c5ed7fd2a70aaad95571fa",
    "preimage": "block:{\"at\":\"2026-11-07T02:49:15.336Z\",\"entry_count\":2,\"first_seq\":194,\"height\":90,\"key_id\":\"key_a521921c2ba20669\",\"last_seq\":195,\"merkle_root\":\"47ccad0f77f53238d7a4e2a4a471a5da46d4e03384e66defcb794b7b6c8465b2\",\"prev_hash\":\"036efb712626a7de2a4e0db28bc3b99cbceb813240dad631969f8522df55166d\",\"v\":1}"
  },
  "calendars": [
    {
      "calendar": "https://a.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:58:43.471Z",
      "updated_at": "2026-11-07T04:58:43.484Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://alice.btc.calendar.opentimestamps.org",
          "commitment": "6aee93e4c8fdaacd3f48c847f53df3e4726c3258157b20358ff0a4a41af39a0c547ef7d1bd234bc655c889b7"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://b.pool.opentimestamps.org",
      "status": "confirmed",
      "submitted_at": "2026-11-07T02:58:43.471Z",
      "updated_at": "2026-11-07T04:58:43.484Z",
      "bitcoin_block_height": 974883,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://bob.btc.calendar.opentimestamps.org",
          "commitment": "6aee93e4ce49e6670985b28d8eb192a96bb9b3daea961d9999fa15fde39558b2a7285ee7490b100d7eb90e97"
        },
        {
          "type": "bitcoin",
          "block_height": 974883,
          "merkle_root": "79abb9dd33baad0a1ff37045cc779f6fe1b133a7037999fbd2c996ad78e43b90"
        }
      ]
    },
    {
      "calendar": "https://finney.calendar.eternitywall.com",
      "status": "pending",
      "submitted_at": "2026-11-07T02:58:43.471Z",
      "updated_at": "2026-11-07T02:58:43.471Z",
      "bitcoin_block_height": null,
      "attestations": [
        {
          "type": "pending",
          "uri": "https://finney.calendar.eternitywall.com",
          "commitment": "6aee93e358151660cdcf7f1983cc2a4c0352873ea0d6251d9760199fbf3bb27ad6c834d56c1c92d898a65bd9"
        }
      ]
    }
  ],
  "proof_url": "https://www.a2ally.com/v1/ledger/blocks/90/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."
}