Technical Design Specification

Architecture Overview

+-------------------+     +-------------------+     +-------------------+
|   Frontend        |     |   AI Framework    |     |   Backend         |
| (Tanstack Start)  |<--->|  (Mastra + MCP)   |<--->| (Hono + Workers)  |
+-------------------+     +-------------------+     +-------------------+
        |                          |                          |
        v                          v                          v
+-------------------+     +-------------------+     +-------------------+
| React Components  |     |       RAG         |     |    API Routes     |
|   (apps/web/)     |     |  (Knowledge Base) |     | (apps/api/src/)   |
+-------------------+     +-------------------+     +-------------------+

Tanstack Start with React Server Components
Client components in apps/web/components/
Shared types in apps/api/src/shared/types.ts

Dependency Management

Shared configs in packages/typescript-config/
ESLint rules from packages/eslint-config/
Turborepo setup in turbo.jsonc
Worker dependencies in wrangler.jsonc

Performance Optimization

LCP <1.2s through server-side rendering
API latency <800ms p95 via Redis caching
Bundling with Vite for frontend assets
WebAssembly modules for OCR processing

Security Implementation

OAuth2 + SAML integration in apps/api/src/lib/better-auth/
AES-256 encryption for stored data
HIPAA-compliant audit logs in apps/api/src/lib/logs/hipaa.ts
Rate limiting via packages/hono-helpers/src/middleware/rate-limit.ts

Scalability Strategy

Horizontal scaling through Kubernetes
10k concurrent user capacity
Database sharding plan in apps/api/drizzle.config.ts
Worker isolation via Turborepo filters (see turbo.jsonc)

Technology Stack

{
	"frontend": {
		"framework": "Tanstack Start with Cloudflare Workers",
		"stateManagement": "React Hook Form + Zod",
		"uiLibrary": "Shadcn UI components (see @shadcn/ui)"
	},
	"backend": {
		"framework": "Hono with Cloudflare Workers",
		"Auth database": "Cloudflare D1",
		"fhir database": "PostgreSQL + pgvector",
		"orm": "Drizzle ORM (see [apps/api/src/db/index.ts](mdc:apps/api/src/db/index.ts))"
	},
	"ai": {
		"framework": "Mastra with Cloudflare Workers",
		"models": "Cloudflare Vectorize for document processing",
		"integration": "REST API from apps/api/ for data access"
	}
}