Build Trace Entry

• 1. Property Build Trace Key
  • 1.1. Property id
• 2. Property Build Trace Value
  • 2.1. Property outPath
  • 2.2. Property dependentRealisations
    • 2.2.1. Pattern Property Dependent Store Path
  • 2.3. Property signatures
    • 2.3.1. Signature
• 3. Property id
• 4. Property outPath
• 5. Property dependentRealisations
• 6. Property signatures

Title: Build Trace Entry

Description: A record of a successful build outcome for a specific derivation output.

This schema describes the JSON representation of a build trace entry.

Warning

This JSON format is currently experimental and subject to change.

1. Property Build Trace Key

Title: Build Trace Key

Description: A build trace entry is a key-value pair. This is the "key" part, refering to a derivation and output.

1.1. Property id

Title: Derivation Output ID

Description: Unique identifier for the derivation output that was built.

Format: {hash-quotient-drv}!{output-name}

• hash-quotient-drv: SHA-256 hash of the quotient derivation. Begins with sha256:.

• output-name: Name of the specific output (e.g., "out", "dev", "doc")

Example: "sha256:ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad!foo"

2. Property Build Trace Value

Title: Build Trace Value

Description: A build trace entry is a key-value pair. This is the "value" part, describing an output.

2.1. Property outPath

Title: Output Store Path

Description: The path to the store object that resulted from building this derivation for the given output name.

2.2. Property dependentRealisations

Title: Underlying Base Build Trace

Description: This is for derived build trace entries to ensure coherence.

Keys are derivation output IDs (same format as the main id field). Values are the store paths that those dependencies resolved to.

As described in the linked section on derived build trace traces, derived build trace entries must be kept in addition and not instead of the underlying base build entries. This is the set of base build trace entries that this derived build trace is derived from. (The set is also a map since this miniature base build trace must be coherent, mapping each key to a single value.)

2.2.1. Pattern Property Dependent Store Path

All properties whose name matches the regular expression ^sha256:[0-9a-f]{64}![a-zA-Z_][a-zA-Z0-9_-]*$ (Test) must respect the following conditions

Title: Dependent Store Path

Description: Store path that this dependency resolved to during the build

2.3. Property signatures

Title: Build Signatures

Description: A set of cryptographic signatures attesting to the authenticity of this build trace entry.

2.3.1. Signature

Title: Signature

Description: A single cryptographic signature

3. Property id

4. Property outPath

5. Property dependentRealisations

6. Property signatures

Examples

Simple build trace entry

{
  "dependentRealisations": {},
  "id": "sha256:ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad!foo",
  "outPath": "g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo.drv",
  "signatures": []
}

Build trace entry with dependencies

{
  "dependentRealisations": {
    "sha256:ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad!foo": "g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo.drv"
  },
  "id": "sha256:ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad!foo",
  "outPath": "g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo.drv",
  "signatures": []
}

Build trace entry with signature

{
  "dependentRealisations": {},
  "id": "sha256:ba7816bf8f01cfea414140de5dae2223b00361a396177a9cb410ff61f20015ad!foo",
  "outPath": "g1w7hy3qg1w7hy3qg1w7hy3qg1w7hy3q-foo.drv",
  "signatures": [
    "asdfasdfasdf"
  ]
}