06 — Build and Slice Loop

Implement features in real vertical slices (UI→API→DB→tests→deploy) starting with the homepage; no placeholders, no stubs.

Vertical-slice principle

Every iteration ships ONE feature end-to-end through every layer (UI → API → DB → tests → deploy). Never half a feature across two passes.

Homepage FIRST (every project, no exceptions)

• First slice is always the homepage hero + nav + footer
• Real H1, real meta tags, real OG card, real JSON-LD
• Deploy before adding any other route — establishes design system, auth layer, analytics tier, deploy pipeline
• Per rules/website-build-doctrine.md Phase 0 / Phase 1

Anti-placeholder (NON-NEGOTIABLE)

• ❌ Lorem ipsum
• ❌ TODO / FIXME / TBD in shipped user-visible strings (source-comment TODOs OK per rules/todos-are-roadmap.md)
• ❌ Gray placeholder boxes / silhouettes
• ❌ "Coming soon" without firm date
• ❌ Stub images / generic SVGs
• ❌ "John Doe" / "Jane Doe" / "company.com" / "example.com"
• ❌ Bracket placeholders [Insert Name] / [Your Title]
• ❌ Single-character "x" / "?" labels

Per rules/copy-writing.md § Production-review copy gate. Build validator greps dist/ for these patterns.

Slice contract (every slice ships ALL of these)

1. Types + Zod schemas at boundaries (rules/zod-everywhere.md)
2. Contract-first API (typed request/response)
3. Loading + empty + error + success states (4-state system per 10-experience-and-design-system)
4. Accessibility (axe 0 violations + WCAG 2.2 AA per _kernel/standards.md#wcag22)
5. 6-breakpoint responsive (per _kernel/standards.md#breakpoints)
6. Observability (Sentry breadcrumb + PostHog event + Workers Trace span)
7. Tests (Vitest unit + Playwright E2E from homepage outward per rules/e2e-testing.md)
8. Feature flag where rollout risk exists (rules/feature-flags.md)
9. Tenant isolation (org_id on every row + every query, 404 on mismatch)
10. Docs (JSDoc on exports + module README)

File organization

Worker (Hono)

src/worker/
├── index.ts              # entry — Sentry wrapper, route mounts, onError, notFound
├── db/
│   ├── schema.ts         # Drizzle source of truth
│   └── index.ts          # getDb helper
├── routes/<feature>.ts   # Hono sub-app per feature
├── lib/<feature>.ts      # business logic
├── middleware/           # auth, tenant, rate-limit
└── types.ts              # Env + Variables

Frontend (React + Vite)

Vite 8 (stable Mar 2026) builds on the unified Rolldown bundler — replaces esbuild+Rollup, 10–30× faster prod builds.

src/web/
├── main.tsx              # entry — router, providers
├── pages/<Page>.tsx      # one per route
├── components/
│   ├── ui/               # shadcn primitives
│   ├── <feature>/        # feature-specific components
│   └── shared/           # Header, Footer, ErrorBoundary
├── lib/                  # api client, auth context, hooks
└── styles.css            # Tailwind + design tokens

Shared

src/shared/
├── plans.ts              # pricing tiers
├── design-styles.ts      # design tokens shared web + worker
└── pageLayout.ts         # shared layout helpers

Tests

e2e/
├── FEATURES.md           # row-per-feature matrix (CI gate)
├── _fixtures/            # page objects
├── _helpers/             # snapshot, axe, breadcrumbs, visual
├── <feature>/
│   ├── happy-path.spec.ts
│   ├── edge-cases.spec.ts
│   ├── a11y.spec.ts
│   └── visual.spec.ts
└── _smoke/               # cross-feature smoke

Build loop (per slice)

1. Write failing test (Playwright TDD-RED first per rules/e2e-testing.md)
2. Author migration (drizzle/0NNN_<feature>.sql) + update db/schema.ts
3. Apply locally (npm run db:apply:local)
4. Implement (route, lib, page, components)
5. Typecheck (npm run typecheck clean)
6. Unit tests (npm test green)
7. Run dev (npm run dev) — exercise in browser
8. Deploy (npm run deploy)
9. Prod E2E (npm run e2e:prod against PROD_URL)
10. Verify console (zero errors, zero CSP violations, zero failed resources)
11. AI vision QA (6bp screenshots → vision rubric ≥9/10)
12. Commit + push (conventional commits per rules/main-only-branch.md)
13. Update e2e/FEATURES.md + CHANGELOG

Real content sourcing

• Copy: brand voice per 09-brand-and-content-system; never AI-default phrasing
• Images: real photos > AI-generated brand-aligned > zero (skill 12)
• Data: real API / Workers AI / D1 query > mocked
• Testimonials: real attribution > none (never fabricated)
• Stats: cited per rules/citations.md

When to stop adding sections

Per rules/website-build-doctrine.md Phase 2: keep adding until next would dilute. Stop when "next hurts," never "we have enough."

See submodules: vertical-slice.md, file-organization.md, anti-placeholder.md.