Commerce Database Architect — Tile Documentation

This Tessl tile bundles the database-architecture intelligence for a high-demand multi-tenant commerce platform. It works in tandem with a Spec Kit project that defines the constitution, ADRs, custom commands, and live schema-state snapshot.

What's inside

Skills

Skills activate automatically when their triggers are matched in user prompts. The seven skills in this tile:

Steering rules (always-on)

• database-non-negotiables — the minimum bar for every interaction
• mcp-safety — rules for Postgres MCP usage
• schema-evolution-discipline — how to handle "add an attribute" requests

Reference snippets

Battle-tested, copy-pasteable SQL for the patterns easy to get wrong:

• reference-snippets/outbox-pattern.md — table + relay + retention
• reference-snippets/rls-templates.md — RLS policies for tenant isolation
• reference-snippets/inventory-movements.md — append-only inventory with balance trigger
• reference-snippets/idempotency-keys.md — idempotency table + middleware pattern
• reference-snippets/optimistic-concurrency.md — version-column pattern
• reference-snippets/expand-contract-migration.md — zero-downtime migration template

Event catalog

event-catalog.md is the source of truth for every domain event the platform emits.

How it pairs with Spec Kit

The Spec Kit project provides the commands and memory:

• .specify/memory/constitution.md — non-negotiable principles
• .specify/memory/architecture-decisions.md — recorded ADRs
• .specify/memory/database-architecture-principles.md — operational rules
• .specify/memory/graph-ai-boundaries.md — Neo4j boundaries
• .specify/memory/eventing-and-audit-principles.md — outbox + audit
• .specify/memory/current-schema-state.md — live snapshot (updated by /speckit.dbsync)
• .specify/memory/schema-change-log.md — append-only history
• .claude/commands/speckit.dbreview.md — review diagrams/schemas/migrations
• .claude/commands/speckit.dbsync.md — refresh the snapshot from MCP
• .claude/commands/speckit.dbevolve.md — schema evolution workflow
• .claude/commands/speckit.adr.md — auto-draft ADRs

The Tessl tile provides the portable, evaluable, versioned skills that travel across Claude Code, Cursor, Codex, Gemini, and Copilot.

Typical session flow

User: [pastes Mermaid diagram]
  ↓
mermaid-diagram-review skill activates
  ↓ (loads constitution + snapshot, runs 12-row check table)
returns 5-section structured response
  ↓
User accepts counter-proposal
  ↓
schema-evolution-workflow skill activates
  ↓ (5-placement analysis, blast radius, expand/contract)
returns migration plan + tests + change-log entry
  ↓
[ADR triggered if deviation detected]
  ↓
adr-drafting skill activates
  ↓
returns Proposed ADR
  ↓
User runs migration
  ↓
User runs /speckit.dbsync
  ↓
postgres-schema-introspection skill activates
  ↓
snapshot refreshed, drift report shown

Setup

See the top-level README.md of the project for installation, .mcp.json configuration, and the first-time walkthrough.

Versioning

Every breaking skill change bumps the tile MINOR version. Backward-compatible changes bump PATCH. Major rewrites bump MAJOR. The current version lives in tile.json.

When you bump, run:

tessl skill review .
tessl tile lint .
tessl eval run .
tessl tile publish . --workspace your-workspace