# Certificate Format
A conformance certificate is a structured report that records everything required to reproduce and evaluate a conformance run.
## Required Fields
| `backend_id` | Name and version of the backend under test |
| `suite_version` | Version of vyre-conform that produced the certificate |
| `timestamp` | ISO 8601 timestamp of the run |
| `level` | L1, L2, L3, or L4 |
| `operation_versions` | Map of op ID → spec version tested |
| `engine_versions` | Map of engine ID → spec version tested |
| `seeds` | Deterministic seeds used for generation |
| `coverage` | Component and overall coverage scores |
| `law_results` | Pass/fail per operation per law |
| `invariant_results` | Pass/fail per engine per invariant |
| `composition_results` | Pass/fail per generated chain |
| `performance_baselines` | Throughput per op (L4 only) |
| `failures` | List of all failures with counterexamples |
| `regression_count` | Number of regressions replayed |
## Properties
- **Deterministic reproduction**: Given the certificate, suite version, and backend, the same inputs can be regenerated and retested.
- **Archival stability**: Old certificates remain interpretable because operation versions and level definitions are permanent.
- **Comparability**: Two certificates for the same suite version can be diffed to see which backend is stronger.
## Usage
A downstream project can require:
```text
"L4 conformance for vyre-conform >= 0.5.0"
```
and verify the claim by inspecting the certificate rather than trusting the backend vendor.