AI-Pair-Programming for Indie Hackers: Prompt Patterns That Actually Ship

What this playbook gives you (and why it works)

• Proven prompt skeletons for UI, DB, auth, and payments—the core of most SaaS apps.

• AI bug-fixing prompts, AI refactor prompts, and AI UI prompts that reduce back-and-forth.

• The Triangle Prompt framework you can reuse everywhere: Context → Spec → Constraints.

• A guardrail checklist for security, performance, and readability.

• When not to use AI (and what to do instead).

Prompt Templates (UI, DB, auth, payments)

Tip: Keep prompts under 400–600 words, attach or paste the relevant code, and ask for a diff. You want small patches you can review, not a 3,000-line mystery.

UI prompt (Next.js + React + Tailwind)

You are my AI pair-programmer. Work in Next.js (App Router), React Server Components where sensible, and Tailwind.

CONTEXT:
- Project: [SaaS name]
- Page: [e.g., /pricing]
- Current files: [list or paste snippets]
- Design tone: clean, focused, fast to first action

SPEC:
- Build a [hero + 3 benefits + pricing tiers + FAQ accordion]
- Mobile-first, responsive container, semantic HTML
- Add test IDs where meaningful (data-testid)

CONSTRAINTS:
- Keep components small and composable
- Avoid inline styles; use Tailwind utilities
- Export a single `<PricingPage />` and child components
- Return a unified patch/diff touching only these files: [file1, file2]
- Add an accessibility pass: proper headings, labels, alt text

• “Reduce CLS and improve first contentful paint.”

• “Extract pricing tier to <TierCard /> with props and prop types.”

• “Add an empty-state for zero features—no console warnings.”

DB prompt (MongoDB models + queries)

You are my AI pair-programmer. Use MongoDB with Mongoose.

CONTEXT:
- Feature: [e.g., Projects and Tasks in a tiny SaaS]
- Scale: low volume to start, simple analytics later

SPEC:
- Create Mongoose schemas + models for:
  - User { email, role, subscriptionStatus, provider, currentPeriodEnd }
  - Project { ownerId, name, createdAt }
  - Task { projectId, title, status, dueAt, createdAt }
- Add basic indexes and a query to fetch:
  - "All active tasks for a user’s current project" with pagination

CONSTRAINTS:
- Validate required fields; minimal enums for status
- Add lean() where returning read-only
- Avoid N+1 queries; show the aggregation or join pattern you choose
- Return a patch/diff for /lib/db/* only

• “Add soft-delete (deletedAt) and ensure queries exclude deleted.”

• “Introduce optimistic concurrency for updates on Task.”

Auth prompt (magic link + Google OAuth)

You are my AI pair-programmer. We need auth with magic link + Google OAuth.

CONTEXT:
- Next.js App Router
- Email provider: [e.g., Resend]
- Session: JWT in HttpOnly cookie

SPEC:
- Implement "Sign in with email" (magic link) and "Continue with Google"
- Store user { userId, email, provider }
- After first login: redirect to /dashboard and run onboarding

CONSTRAINTS:
- Secure cookie flags (HttpOnly, Secure, SameSite)
- CSRF protection on POST routes
- Rate-limit magic link requests by IP + email
- Return handlers, routes, and a single `useAuth()` hook
- Provide test flow: local dev + dummy values

• “Add a requireActiveSubscription middleware for protected routes.”

• “Return explicit error codes for auth failures and throttle responses.”

Payments prompt (Stripe OR Lemon Squeezy)

You are my AI pair-programmer. Add subscriptions.

CONTEXT:
- Plans: Starter $[x]/mo, Pro $[y]/mo, annual with 2 months free
- Provider: [Stripe Billing | Lemon Squeezy]
- User has fields: subscriptionStatus, planId, currentPeriodEnd

SPEC:
- Create a pricing page with 2 tiers + annual toggle
- Implement hosted checkout first (fastest path)
- Webhook: on payment succeeded → set user active + currentPeriodEnd
- Webhook: on cancellation/failed payment → set past_due or canceled
- Self-serve: [Stripe Portal | LS customer management flow]

CONSTRAINTS:
- Verify webhook signatures; idempotency on event processing
- Keep business logic in /lib/billing/*
- Add a minimal receipts email and trial-ending email
- Return a patch/diff for pricing + billing only

• “Add coupons and test proration on upgrade.”

• “Instrument dunning/retries and log all billing events for 30–60 days.”

Want the end-to-end flow wired for you (auth → DB → email → subscriptions → launch)? Start now.

AI bug fixing prompts (fast, surgical)

You are my AI debugger. Work only in the files shown.

CONTEXT:
- Failing test: [paste test + failure trace]
- Code under test: [paste relevant snippet]
- Expected behavior: [1–2 lines]

TASK:
- Explain root cause in 2–3 bullets
- Provide a minimal diff that fixes the bug
- List side effects + what to retest

CONSTRAINTS:
- No new dependencies
- Keep the patch under 30 lines
- Maintain existing public API

AI refactor prompts (clarity without surprises)

You are my AI refactor partner.

CONTEXT:
- File(s): [paths]
- Pain points: [duplication, long function, mixed concerns]

TASK:
- Improve naming, extract pure functions, remove dead code
- Keep behavior identical (add a small test if missing)

CONSTRAINTS:
- Max patch 100 lines, explain changes in bullets
- No new runtime deps
- Add JSDoc for exported functions

AI UI prompts (micro-interactions that convert)

You are my UI polish partner.

CONTEXT:
- Component: [e.g., Pricing CTA section]
- Audience: first-time visitors, mobile heavy

TASK:
- Add a subtle scroll-based fade-in
- Improve button focus/hover states with Tailwind
- Ensure accessible contrast and focus rings

CONSTRAINTS:
- Avoid layout shift
- Keep animations under 200ms
- Return only the component diff + a short test for styles via test IDs

The “Triangle” Prompt (context → spec → constraints)

• Context: What exists? What stack, files, routes, users?

• Spec: What must change? What is the outcome in plain language?

• Constraints: What must not change? Limits, tests, budgets, APIs.

From vague to precise (before/after)

A full Triangle example

CONTEXT:
- Next.js App Router. Empty /app/pricing/page.tsx.
- Tailwind installed. Layout already wraps children.

SPEC:
- Add hero, 3 benefits, 2 pricing tiers, FAQ accordion.
- Annual toggle with computed prices (+ yearly saving note).
- CTA button triggers hosted checkout (placeholder function).

CONSTRAINTS:
- Accessible headings/labels; no inline styles.
- Keep components small; export <PricingPage /> default.
- Return a unified diff under 150 lines; no extra files.

Guardrails: security, performance, readability

• Security: Validate input, sanitize output, never log secrets, use HttpOnly cookies, CSRF on mutations, verify webhook signatures.

• Performance: Avoid N+1, use pagination, cache obvious reads, keep bundle small, avoid layout shift.

• Readability: Small components, clear names, JSDoc on exports, strict TypeScript types, no new deps unless justified.

• Testing: Include or update a minimal test for the change.

• Diff discipline: Single, reviewable patch; list any risks.

Workflow that keeps you fast (and sane)

• One feature = one branch = one prompt thread. Keep history tidy.

• Always ask for a diff. “Return a unified patch touching only X.”

• Two-pass approach: first generate → then “audit your patch vs constraints.”

• Local tests first. Don’t trust green text from the model.

• Name your prompts. Save reusable ones as snippets (UI, DB, auth, payments, AI bug fixing prompts, AI refactor prompts, AI UI prompts).

When not to use AI (and what to do instead)

• Critical secrets or compliance-sensitive code. Hand-write, review, and document.

• Migrations that risk data loss. Design on paper, write explicit steps, test against copies.

• Unknown domains. Read docs first; then prompt with a clear spec.

• Tiny tasks under 10–20 lines. Just code it faster than you can explain.

• High-stakes architecture decisions. Brainstorm with AI if you want, but decide after sketching trade-offs yourself.

FAQ

Wrap-up

• Structure beats wordy prompts. Context, spec, constraints—always.

• Ask for diffs and tests. Review like a pro.

• Keep your stack simple (Next.js, MongoDB, auth, payments), and your prompts will sing.

• When you want to turn these patterns into a real, paid app, Join CodeFast Now.