{
  "schemaVersion": 1,
  "generatedAt": "2026-10-17T20:14:01.471997+00:00",
  "sourceSha256": "29d59c9a65dd27cc3fb917f83edf9418b2e42a7f5724fd3f3a2d8911efda14da",
  "environment": {
    "zstd": "*** Zstandard CLI (64-bit) v1.5.5, by Yann Collet ***",
    "python": "3.12.3",
    "system": "Linux",
    "machine": "x86_64"
  },
  "method": {
    "type": "synthetic-codec-contract-demonstration",
    "dictionaryType": "raw-content",
    "dictionaryBytes": 8192,
    "dictionarySha256": "2f5c6a9de7015d18eaeaa439f61b19a38d07da43216cf70bc8910529e21c4622",
    "wrongDictionarySha256": "79a8eec85a76258441af700a5658322999ceb8e38597368d71b26616808a5ae1",
    "payloadBytes": 2048,
    "payloadSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
    "dictionaryIdPresent": false,
    "compressionLevel": 3,
    "commandTimeoutSeconds": 15,
    "acceptance": "zero exit status AND exact expected decoded bytes; payload only, not metadata",
    "skippableMetadata": "generation=0001",
    "changedSkippableMetadata": "generation=0002",
    "checksumMutation": "XOR final checksum byte with 1; compressed data unchanged",
    "scope": "One CLI build; no disk corruption rate, latency or power-loss claim."
  },
  "observations": [
    {
      "id": "plain-control",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 2048,
      "outputSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": true,
      "accepted": true,
      "stderr": "",
      "compressedBytes": 2061,
      "compressedSha256": "3fe52b5a04abf65a05589848f2418ce23214abb9a877220c5605410daf9836ef"
    },
    {
      "id": "dictionary-correct",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 2048,
      "outputSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": true,
      "accepted": true,
      "stderr": "",
      "compressedBytes": 21,
      "compressedSha256": "da61f8ad75554bc3a70f54ba564112e1339f247ec4b08bd809a628ef1d40c66d"
    },
    {
      "id": "dictionary-missing",
      "exitCode": 1,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 0,
      "outputSha256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": false,
      "accepted": false,
      "stderr": "/*stdin*\\ : Decoding error (36) : Data corruption detected",
      "compressedBytes": 21,
      "compressedSha256": "da61f8ad75554bc3a70f54ba564112e1339f247ec4b08bd809a628ef1d40c66d"
    },
    {
      "id": "dictionary-wrong-checked",
      "exitCode": 1,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 0,
      "outputSha256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": false,
      "accepted": false,
      "stderr": "/*stdin*\\ : Decoding error (36) : Restored data doesn't match checksum",
      "compressedBytes": 21,
      "compressedSha256": "da61f8ad75554bc3a70f54ba564112e1339f247ec4b08bd809a628ef1d40c66d"
    },
    {
      "id": "dictionary-wrong-unchecked",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 2048,
      "outputSha256": "216a381ce7b098ae7a736ba297cbd41bcd6035fc8370185bef9a5e40a7ce12c0",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": false,
      "accepted": false,
      "stderr": "",
      "compressedBytes": 17,
      "compressedSha256": "8c6eef2b05a4440053c9e3f8d8aca7f572db35a687b65a9038b227821d302ab4"
    },
    {
      "id": "dictionary-correct-unchecked",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 2048,
      "outputSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": true,
      "accepted": true,
      "stderr": "",
      "compressedBytes": 17,
      "compressedSha256": "8c6eef2b05a4440053c9e3f8d8aca7f572db35a687b65a9038b227821d302ab4"
    },
    {
      "id": "two-frames-complete",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 22,
      "outputSha256": "92d731b8cf04e91a337504feea146e57ceb5c12b38cda1ee1ac2b8562b45d18e",
      "expectedBytes": 22,
      "expectedSha256": "92d731b8cf04e91a337504feea146e57ceb5c12b38cda1ee1ac2b8562b45d18e",
      "bytesMatch": true,
      "accepted": true,
      "stderr": "",
      "compressedBytes": 48,
      "compressedSha256": "dc22de5f19d15fc59004f628f6c12fb71748511e9c2f552a74f3fea46cf9ddee"
    },
    {
      "id": "second-frame-removed",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 11,
      "outputSha256": "6a7690ddf30c9d1562467600561a0174fc09c406f56b8a68d58ca7aff942ccd0",
      "expectedBytes": 22,
      "expectedSha256": "92d731b8cf04e91a337504feea146e57ceb5c12b38cda1ee1ac2b8562b45d18e",
      "bytesMatch": false,
      "accepted": false,
      "stderr": "",
      "compressedBytes": 24,
      "compressedSha256": "3dde12e3adc26227a608c3dea7c80fd16c149eddaa7e9cd69a4892c8e3398989"
    },
    {
      "id": "last-byte-truncated",
      "exitCode": 1,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 22,
      "outputSha256": "92d731b8cf04e91a337504feea146e57ceb5c12b38cda1ee1ac2b8562b45d18e",
      "expectedBytes": 22,
      "expectedSha256": "92d731b8cf04e91a337504feea146e57ceb5c12b38cda1ee1ac2b8562b45d18e",
      "bytesMatch": true,
      "accepted": false,
      "stderr": "/*stdin*\\ : Read error (39) : premature end",
      "compressedBytes": 47,
      "compressedSha256": "9f00199231a7caa475e2092f144fbcb7f32244c4b4e3d8ee4925ec6226fd4d76"
    },
    {
      "id": "dictionary-check-ignored",
      "exitCode": 0,
      "checksumPolicy": "ignore",
      "outputBytes": 2048,
      "outputSha256": "216a381ce7b098ae7a736ba297cbd41bcd6035fc8370185bef9a5e40a7ce12c0",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": false,
      "accepted": false,
      "stderr": "",
      "compressedBytes": 21,
      "compressedSha256": "da61f8ad75554bc3a70f54ba564112e1339f247ec4b08bd809a628ef1d40c66d"
    },
    {
      "id": "checksum-damaged-verified",
      "exitCode": 1,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 0,
      "outputSha256": "e3b0c44298fc1c149afbf4c8996fb92427ae41e4649b934ca495991b7852b855",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": false,
      "accepted": false,
      "stderr": "/*stdin*\\ : Decoding error (36) : Restored data doesn't match checksum",
      "compressedBytes": 2061,
      "compressedSha256": "2b136363a7c2713c6a5f321a573b686be37db9eb76443a6f0169f01ae503857a"
    },
    {
      "id": "checksum-damaged-ignored",
      "exitCode": 0,
      "checksumPolicy": "ignore",
      "outputBytes": 2048,
      "outputSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": true,
      "accepted": true,
      "stderr": "",
      "compressedBytes": 2061,
      "compressedSha256": "2b136363a7c2713c6a5f321a573b686be37db9eb76443a6f0169f01ae503857a"
    },
    {
      "id": "skippable-metadata-original",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 2048,
      "outputSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": true,
      "accepted": true,
      "stderr": "",
      "compressedBytes": 2084,
      "compressedSha256": "1bcf3ca91a8c11a771e3efba6beea90d82da424262fdec67f348c355ee84ab03"
    },
    {
      "id": "skippable-metadata-changed",
      "exitCode": 0,
      "checksumPolicy": "verify-if-present",
      "outputBytes": 2048,
      "outputSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "expectedBytes": 2048,
      "expectedSha256": "67d7037a86fafee1ab30188568f4511516d581050195b2ccf4e0c0d1363451ea",
      "bytesMatch": true,
      "accepted": true,
      "stderr": "",
      "compressedBytes": 2084,
      "compressedSha256": "523c05453ad2d3dbe9d11fc85672ac30732755028d9404791ab95d75965e07df"
    }
  ]
}