Building a B2B SaaS in 2025? You typically face two lousy options:
- Pay $250 to $1,000 for a "Premium Boilerplate" that promises to save you time.
- Spend 3 weeks building Auth, Billing, and RBAC before you write a single line of product code.
Neither is great.
The "boring" infrastructure (Auth, Payments, Admin Dashboards) should be free and standard by now. So I spent the last week auditing the best open source starter kits that genuinely compete with the paid alternatives.
Here are the top 5 production-ready stacks you can clone right now and save yourself $1,000.
1. The "High-Performance" Option: Go B2B Starter
Best for: Founders who want batteries-included integrations without the cloud bill.
Most starter kits hand you a "Hello World"…
Building a B2B SaaS in 2025? You typically face two lousy options:
- Pay $250 to $1,000 for a "Premium Boilerplate" that promises to save you time.
- Spend 3 weeks building Auth, Billing, and RBAC before you write a single line of product code.
Neither is great.
The "boring" infrastructure (Auth, Payments, Admin Dashboards) should be free and standard by now. So I spent the last week auditing the best open source starter kits that genuinely compete with the paid alternatives.
Here are the top 5 production-ready stacks you can clone right now and save yourself $1,000.
1. The "High-Performance" Option: Go B2B Starter
Best for: Founders who want batteries-included integrations without the cloud bill.
Most starter kits hand you a "Hello World" with Stripe and leave you to figure out the rest. Go B2B Starter is different. It comes with the heavy-lifting integrations pre-wired out of the box.
Instead of locking you into expensive wrappers, it integrates best-in-class specialized tools:
Billing: Polar.sh (Merchant of Record) is fully integrated. No more fighting with Stripe webhooks or tax compliance. It handles global tax and VAT automatically.
Auth & RBAC: Stytch implementation is built-in, complete with a multi-tenant permission system (Owner, Admin, Viewer roles). No custom middleware required.
AI Engine: A full OpenAI RAG pipeline using pgvector is wired up and ready. Build AI apps immediately without setting up Pinecone or LangChain.
Infrastructure: Uses a Modular Monolith architecture (Go + Next.js) packaged in Docker. You can host the entire stack on a $5 Hetzner or DigitalOcean VPS.
2. The "Full Stack JS" Option: Open SaaS
Best for: React/Node.js developers who love frameworks.
If you want to stay in the JavaScript ecosystem, Open SaaS is widely considered the gold standard. It is built on Wasp, a configuration language (DSL) that glues React and Node.js together.
Integrations: Stripe, SendGrid (Email), and Plausible (Analytics) are ready to go.
Pros: Heavily opinionated, which means fewer decisions for you.
Cons: You need to learn the Wasp DSL syntax. This can feel like a bit of lock-in compared to standard Express or Go.
3. The "Python" Option: Cookiecutter Django
Best for: Django developers.
SaaS Pegasus is the paid gold standard in the Python world, but Cookiecutter Django is the community-driven open source alternative that has stood the test of time.
If you prefer Django’s "batteries-included" philosophy over strict typing, this is your safest bet. It handles complex data modeling exceptionally well, though it can be heavier on memory usage than a Go backend.
4. The "Minimalist" Option: Taxonomy
Best for: Simple indie tools.
Sometimes you do not need Enterprise RBAC or an AI pipeline. If you just want a simple Next.js app that can take money, Taxonomy (built by the creator of shadcn/ui) is a great open source choice.
It connects Next.js to Stripe and Supabase. Lightweight, clean, and perfect for Micro-SaaS apps that do not need complex team management features.
5. The "Enterprise" Option: BoxyHQ
Best for: Selling to Fortune 500s.
If your first customer is a massive enterprise, you need SAML SSO (Single Sign-On) and Audit Logs from day one. BoxyHQ specializes in exactly this. Their SaaS Starter is essentially a wrapper around their Enterprise SSO product.
Overkill for a todo list app. Mandatory if you are selling to banks or hospitals.
TL;DR: Which One Should You Pick?
| Use Case | Pick This |
|---|---|
| Raw performance, AI integrations, self-hosting | Go B2B Starter |
| Pure JavaScript ecosystem | Open SaaS |
| Python / Django | Cookiecutter Django |
| Minimalist Micro-SaaS | Taxonomy |
| Enterprise SSO requirements | BoxyHQ |
Stop rewriting Auth. Clone one of these and ship your product.