# VEX-Rekor Linkage

## Module
devops

## Status
IMPLEMENTED

## Description
Database migration linking VEX observations to Rekor entries for transparent VEX decision tracking.

## Implementation Details
- **VEX Proof Integrator**: `src/Attestor/__Libraries/StellaOps.Attestor.ProofChain/Generators/VexProofIntegrator.Helpers.cs` and `VexProofIntegrator.Metadata.cs` -- integrates VEX verdicts with proof chain by generating Rekor-linked evidence, binding VEX decisions to transparency log entries.
- **VEX Verdict Proof Payload**: `src/Attestor/__Libraries/StellaOps.Attestor.ProofChain/Generators/VexVerdictProofPayload.cs` -- payload model for VEX verdict proofs containing Rekor entry references.
- **VEX Verdict ID**: `src/Attestor/__Libraries/StellaOps.Attestor.ProofChain/Identifiers/VexVerdictId.cs` -- content-addressed identifier for VEX verdicts, used to link VEX observations to their Rekor transparency log entries.
- **VEX Delta Models**: `src/Attestor/__Libraries/StellaOps.Attestor.ProofChain/Predicates/VexDeltaChange.cs`, `VexDeltaStatement.cs`, `VexDeltaSummary.cs` -- models for tracking VEX status changes across Rekor-linked observations.
- **VEX Merge Trace**: `src/Attestor/__Libraries/StellaOps.Attestor.ProofChain/Predicates/VexMergeTrace.cs` -- audit trace for VEX statement merges, including Rekor entry references for each source.
- **Compose Configuration**: `devops/compose/docker-compose.stella-ops.yml` -- Docker Compose with PostgreSQL services supporting VEX-Rekor linkage tables.

## E2E Test Plan
- [ ] Create a VEX verdict via the proof chain pipeline and verify it generates a Rekor entry with the VEX payload; confirm the linkage is persisted in PostgreSQL with both the VEX verdict ID and Rekor log index
- [ ] Query VEX observations by Rekor entry and verify the linked VEX status (affected, not_affected, under_investigation) is correctly returned
- [ ] Update a VEX status and verify a new Rekor entry is created; confirm the delta change record links both the old and new Rekor entries
- [ ] Verify the VEX merge trace includes Rekor references for each merged source statement
- [ ] Verify the linkage survives database migration: run the migration on an existing database and confirm existing VEX-Rekor links are preserved