# Design Index

## Main Narrative

- [V1 lakehouse architecture](./v1-lakehouse-architecture.md) — scope, non-goals, principles, reference architecture, contract model, governance, and open questions.

## Contract System

- [V0 authored contract schema](./v0-authored-contract-schema.md) — Git-authored YAML contract shape.
- [V0 runtime-served contract view schema](./v0-runtime-served-contract-view-schema.md) — agent/runtime-facing JSON snapshot shape.
- [V0 contract engine](./v0-contract-engine.md) — compiler that discovers, collates, validates, projects, publishes, and suggests contract changes.

Machine-readable schemas:

- [Authored contract JSON Schema](../../schemas/data-product-contract.authored.v0.schema.json)
- [Runtime view JSON Schema](../../schemas/data-product-contract.runtime-view.v0.schema.json)

## Orchestration

- [Orchestration on Airflow 3 Assets current-state companion](./orchestration-airflow3-assets-investigation.md) — companion evidence for ADR 0020. Records current local Airflow 3.2 implementation status, remaining gates, and still-deferred decisions without reopening the orchestration engine decision.

## Governance And Agents

- [V0 governance classifications](./v0-governance-classifications.md) — starter classification hierarchy and default policy mapping.
- [V0 agent runtime API](./v0-agent-runtime-api.md) — product-first API shape for discovery, inspection, governed query, and action requests.

## Deferred Decisions

Deferred by design:

- Observed-lineage event model
- Generated docs rendering shape
- Bespoke agent permission model
- Detailed approval workflow
- Full governance policy language
- Production implementation design

## Platform Principles

- [Config-driven clean structure](../principles/config-driven-clean-structure.md) — reusable engine code stays separate from source-owned config, contracts, secrets, and run artifacts.