$49·Payments·Popular

MVP Auth + Stripe Billing DevSpec Pack

A focused DevSpec pack that composes free HACODE starter + Auth.js + Stripe modules and adds the entitlements matrix and webhook idempotency checklist agents skip. Includes explicit 10-minute path: signed-in → Checkout → verified webhook → gated route (never grant from success_url). Delivered as markdown + skill files with env patterns, smoke test, human-dev handoff, Cursor rules + Claude skill, and three annotated vague-vs-DevSpec runs. Stack locked: Next.js App Router · Auth.js v5 (JWT) · Stripe Checkout subscriptions · Prisma. Not a Notion template, not a prompt dump, not a full multi-tenant boilerplate.

Works With Any AI Tool

This DevSpec works with all AI coding assistants and LLMs.

CursorClaudeCopilotChatGPTGeminiAny LLM

What's Included

✓START-HERE.md with 10-minute path: sign in → checkout → webhook → gated route
✓DEVSPEC.md — Composed Auth + Stripe Billing system specification
✓SKILL.md + .cursorrules — Claude Code skill and Cursor integration
✓MODULE-MAP.md — Order for composing free HACODE Auth + Stripe packs
✓ENTITLEMENTS.md — Free → Paid event-driven access gates (never grant from success_url)
✓WEBHOOK-IDEMPOTENCY-CHECKLIST.md — Prevent duplicate entitlements
✓ENV-EXAMPLE.md — Environment patterns and secrets checklist
✓SMOKE-TEST.md — Step-by-step verification path
✓HANDOFF-HUMAN-DEV.md — What to do if AI stalls
✓CHECKLIST.md — Complete implementation checklist
✓FAQ.md — Common integration footguns and limits
✓SAMPLE.md — Redacted 10-minute stranger walkthrough
✓SAMPLES/ — 3 annotated before/after agent runs (vague vs DevSpec-driven)
✓CONTENTS.md — Full file inventory
✓Stack: Next.js App Router, Auth.js v5 JWT, Stripe Checkout subscriptions, Prisma
✓Auth gate vs entitlement gate separation patterns
✓Production webhook signature verification

File Structure

17 files in this pack

📄README.mdSetup guide

📄DEVSPEC.mdAI specifications

📁src/Source structure

📄app/Application code

📄components/React components

📄lib/Utilities

📄package.jsonDependencies

📄Config filesTypeScript, Tailwind, etc.

Tech Stack

Next.js App RouterAuth.js v5StripePrismaTypeScript

What you get in 10 minutes

A stranger can follow the pack's money path with test keys only, no production secrets, and see Auth → Checkout → Webhook → Gated route.

Min 0–2

Point the agent at DEVSPEC.md + env setup — starter → auth → stripe → entitlements for a single "pro" subscription

Min 2–5

Sign-in working, POST /api/checkout returns Stripe URL, POST /api/webhooks/stripe verifies signatures

Min 5–8

Run the happy path: sign in → blocked page → checkout with 4242 4242 4242 4242 → webhook fires → page unlocks

Min 8–10

Prove you didn't cheat: resend event → still one entitlement, cancel subscription → page locks again

GET /api/me/access (redacted example)

{
  "authenticated": true,
  "entitlements": [
    {
      "key": "pro",
      "status": "active",
      "validUntil": null
    }
  ]
}

Who It's For

Solo founders, freelancers, and small agencies using AI coding tools who need a finished Auth → Checkout → Entitlement path this week

Time Saved

DIY: 8-20 hours

With DevSpec: minutes

Package

17 files

Specs + scaffolds + config