# VEX Delta Persistence Table

## Status
VERIFIED

## Description
Persistent tracking of VEX status transitions between artifact versions with rationale and replay hashes. Schema designed but not implemented.

## Why Marked as Dropped (Correction)
**FINDING: VEX delta persistence IS implemented across multiple modules.** The following exist:
- `src/Excititor/__Libraries/StellaOps.Excititor.Persistence/Postgres/Repositories/PostgresVexDeltaRepository.cs` -- PostgreSQL VEX delta repository
- `src/VexLens/StellaOps.VexLens/Services/VexDeltaComputeService.cs` -- VEX delta computation
- `src/VexLens/StellaOps.VexLens/Mapping/VexDeltaMapper.cs` -- VEX delta data mapping
- `src/VexLens/StellaOps.VexLens/Storage/InMemoryConsensusProjectionStore.cs` -- in-memory projection store
- `src/VexLens/StellaOps.VexLens.Persistence/Repositories/ConsensusProjectionRepository.cs` -- persistent consensus projections
- `src/VexLens/StellaOps.VexLens.Persistence/Postgres/VexLensDataSource.cs` -- PostgreSQL data source
- `src/SbomService/__Libraries/StellaOps.SbomService.Lineage/Repositories/VexDeltaRepository.cs` -- SBOM lineage VEX delta tracking
- `src/SbomService/__Libraries/StellaOps.SbomService.Lineage/Persistence/Migrations/00001_InitialSchema.sql` -- migration with VEX delta tables
- Attestor proof chain predicates: `VexDeltaPredicate.cs`, `VexDeltaSummary.cs`, `VexDeltaChange.cs`, `VexDeltaStatement.cs`

## Implementation Details
- Excititor persistence: `src/Excititor/__Libraries/StellaOps.Excititor.Persistence/Postgres/Repositories/PostgresVexDeltaRepository.cs`
- VexLens computation: `src/VexLens/StellaOps.VexLens/Services/VexDeltaComputeService.cs`
- VexLens mapping: `src/VexLens/StellaOps.VexLens/Mapping/VexDeltaMapper.cs`
- SbomService lineage: `src/SbomService/__Libraries/StellaOps.SbomService.Lineage/Repositories/VexDeltaRepository.cs`
- Attestor predicates: `src/Attestor/__Libraries/StellaOps.Attestor.ProofChain/Predicates/VexDelta*.cs`

## E2E Test Plan
- Verify VEX delta computation tracks status transitions correctly
- Test persistence and retrieval of VEX deltas
- Validate consensus projection store maintains correct state
- Test delta predicates are included in proof chain attestations

## Source
- Feature matrix scan

## Notes
- Module: Excititor
- Modules referenced: `src/Excititor/`, `src/VexLens/`, `src/SbomService/`
- **Status should be reclassified from NOT_FOUND to IMPLEMENTED**

## Verification
- Verified on 2026-02-13 via `run-001`.
- Tier 0: Source files confirmed present on disk.
- Tier 1: `dotnet build` passed (0 errors); 503/504 tests passed (1 env_issue: no local Postgres).
- Tier 2d: `docs/qa/feature-checks/runs/excititor/vex-delta-persistence-table/run-001/tier2-integration-check.json`