Implementation Plan: Sprint 1 “Walking Skeleton”

Phase 0 Artifact — Establishes the initial end-to-end connectivity per ENGINEERING.SOP.md Phase 0.

Purpose

The “Walking Skeleton” is a tiny implementation of the system that performs a small end-to-end function. It links the main architectural components together:

  1. Semantic Intake (SEA-DSL)
  2. Cognitive Processing (LLM/Embeddings)
  3. Governance Check (Policy)
  4. Persistence (Vector/Graph)
  5. Output (UI/Artifact)

Goal: Prove connectivity and stack viability before building features.

Updated 2025-12-30: Adjusted for local-first stack (pgvector, Gemma, Oxigraph).

The “Golden Thread”

We will implement a single vertical slice: “Ingest a SEA-DSL policy, index it, and query it.”

  1. Ingest: Parse policy.sea (SEA-DSL)
  2. Index: Store RDF triples in Oxigraph + Embeddings in pgvector
  3. Query: Ask “What is this policy?” -> Retrieve via Vector Search -> Synthesize answer
  4. Govern: Check “Am I allowed to see this?” via OPA

Technical Stack (Phase 0)

Component Selection Justification
Vector Store pgvector Zero-infrastructure local vector search.
Embeddings EmbeddingGemma Deterministic, local-first via llama.cpp.
Knowledge Graph Oxigraph High-perf RDF store (Rust) with SPARQL.
Policy Engine OPA (Rego) Standard governance enforcement.
Orchestration Semantic Kernel Lightweight agent flow.

Proposed Cycles

Cycle Branch Feature Stack
S1A cycle/s1-skeleton-ingest Parse + Index tree-sitter + oxigraph
S1B cycle/s1-skeleton-memory Vector Search pgvector + llama.cpp
S1C cycle/s1-skeleton-govern Policy Check opa
S1D cycle/s1-skeleton-query RAG Loop semantic-kernel

Validation & Verification

References