Next.js 15 App Router Registration Form with Zod & Server Actions
30 Production Challenge Scenarios • Real-Time Automated Quality Scoring
Interactive Prompt Engineering Lab
Test and score your prompts against real-world enterprise scenarios. Get immediate 4-axis quality telemetry, negative guardrail verification, and golden reference prompts.
1. Authoritative Persona
Expert role + zero fluff
2. Deterministic Schema
XML tags + JSON / keys
3. Negative Guardrails
NEVER / fallback rules
4. Token Efficiency
150–1,800 chars concise
Web & System ArchitectureIntermediate
Next.js 15 App Router Registration Form with Zod & Server Actions
Generate a production-ready Next.js 15 Server Action and form component that validates user registration, hashes passwords with bcrypt, checks database uniqueness, and handles pending state gracefully.
Target Input Context / Untrusted Data:
Framework: Next.js 15 (React 19, Server Actions, 'use server') Schema: Username (min 3 chars, alphanumeric), Email (RFC-compliant), Password (min 12 chars, mixed case, symbol) Database: Prisma ORM with PostgreSQL Security: Rate-limit protection, bcrypt hash with salt rounds 12, CSRF safety.
Quality Requirements & Guardrails:
Define a Principal Full-Stack React Architect persona.
Use native Next.js 15 useActionState hook for optimistic status and pending indicators.
Implement strict Zod schema parsing inside the server action.
Never return raw database error messages or stack traces to the client.
Your System Prompt Draft
75 chars~19 tokens
Golden Reference Architecture (100% Quality Benchmark)
<system_instructions>
You are a Principal Full-Stack Engineer specializing in Next.js 15 App Router, React 19, and secure TypeScript development.
Generate a production-grade registration system consisting of:
1. A Zod validation schema.
2. A Next.js 15 Server Action (`registerUserAction`).
3. A client component form using React 19 `useActionState`.
STRICT ARCHITECTURAL RULES:
- Use 'use server' at the top of the server action file.
- Validate inputs server-side with `RegisterSchema.safeParse(formData)`.
- Hash passwords using bcryptjs with at least 12 salt rounds before database insertion.
- Return structured state: `{ success: boolean, errors?: Record<string, string>, message?: string }`. Never throw unhandled exceptions to the UI.
- Use Tailwind CSS with dark mode classes, showing inline field errors and a disabled spinner state during submission.
- Output clean TypeScript files inside <file path="..."> tags.
</system_instructions>