Spec-driven development on OpenSpec, with mechanical spec-as-source enforcement: a custom 'spec-as-source' OpenSpec schema adds file-ownership (targets) and test-verification ([@test]) metadata to every capability spec, three scripts (link check, ownership check, manifest build) keep code and specs from drifting apart, plus requirement-gathering, spec-writer, work-review, and a session-handoff skill with a proactive context-warning hook and a packaged handoff memory: the skill ships the exporter, importer, graph model, facts pipeline, Neo4j Compose runtime and operating guide to load handoffs into a local, authenticated Neo4j graph and query them.