SaaS Starter Kit: The Open-Source SaaS Foundation That Saves You 40-80 Hours

SaaS Starter Kit: The Open-Source SaaS Foundation That Saves You 40-80 Hours

Every B2B SaaS needs the same boring-but-critical plumbing before you can build the actual product: authentication, organizations, roles, billing hooks, API keys, audit trails. That’s 40–80 hours gone before you write a single line of your idea.

The SaaS Starter Kit is a production-grade TypeScript foundation that does that plumbing for you — and it follows the open-source-first model that works: the core is free on GitHub, the Pro kit is $99.99 one-time.

👉 Get the full SaaS Starter Kit on Gumroad ($99.99)

What You Get

Built as a real startup MVP, not a demo:

  • Next.js 16 (App Router) + TypeScript — strict typing end to end
  • PostgreSQL + Prisma — schema, migrations, seeded demo tenant (owner@acme.test)
  • Auth.js v5 — email/password + OAuth, ready to extend
  • Multi-tenancy + RBAC — organizations, teams, roles, and a PERMISSIONS map that makes authorization declarative
  • Stripe billing hooks — the webhook already verifies signatures and syncs subscription state
  • API keys + audit logs — every request is attributable
  • Real MVP seams — swap in Resend for invites, Inngest/Trigger.dev for background jobs

The Free → Pro Model

  • Free (MIT, GitHub): the entire open-source core — clone it, run npm run dev, and you have a working multi-tenant MVP. The README walks you through database setup, demo data, and a Vercel/Neon deploy path.
  • Pro ($99.99 one-time): the 90-second setup walkthrough, deploy help, priority support, and lifetime updates — you’re not paying for code, you’re paying for the hours you don’t spend hunting environment-variable errors at 2am.

👉 Get the full SaaS Starter Kit on Gumroad ($99.99)

Who It’s For

  • Solo founders shipping their first B2B SaaS without a senior backend engineer
  • Freelancers and agencies who build client MVPs and need a secure, typed starting point
  • Indie hackers who’d rather spend 40 hours on their product than on their auth

What It Is Not (Being Honest)

  • Not a no-code builder — you write TypeScript. If you don’t want to touch code, this isn’t it.
  • Not a magic AI generator — the code is hand-written and production-grade; you extend it yourself.
  • Not a full product — it’s the foundation. Your idea is still the 90%.

That’s the point: honest, boring, reliable plumbing — so the time you save goes into the part that actually differentiates your product.

The Verdict

At $99.99 one-time with a free MIT core you can inspect before you pay, the SaaS Starter Kit is one of the few dev purchases where the risk is close to zero: clone the repo, read the code, and only buy the Pro kit if the walkthrough, support, and updates are worth more to you than the 40–80 hours it saves.

👉 Get the full SaaS Starter Kit on Gumroad ($99.99)

Pair it with the AI Developer Stack Bundle ($79) to add Cowork Pro and the DGX Spark Kit, or start with the AI Starter Bundle ($49) if you’re earlier in your AI journey.

About the author
Published by slashman413 — writing practical, evergreen guides on money, productivity, developer tooling and the web. More about this site →

Frequently Asked Questions

What does the SaaS Starter Kit include?

A production-grade TypeScript foundation: Next.js 16 (App Router), PostgreSQL + Prisma, Auth.js v5 (email + OAuth), organizations/teams with roles, Stripe billing hooks, API keys, audit logs, and a seeded demo tenant — the boring-but-critical plumbing every B2B SaaS needs before the actual product.

Is there a free version?

Yes. The open-source core is on GitHub (MIT) and runs a complete multi-tenant MVP. The Pro kit on Gumroad adds a 90-second setup walkthrough, deploy help, priority support, and lifetime updates.

Who is this for?

Solo founders, freelancers and small teams shipping their first B2B SaaS who want a secure, typed foundation instead of gluing boilerplate together for 40-80 hours. You should be comfortable with TypeScript and React.

What does the $99.99 Pro kit include that the free repo does not?

A 90-second setup walkthrough (env, DB, Stripe keys), deploy help for Vercel/Neon, priority support from the maintainer, and lifetime updates as the stack evolves.

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