Show HN: Open Source B2B SaaS Starter Kit (Go, Next.js, RBAC, Polar)

Hi HN,

I realized I was spending the first 3 weeks of every new B2B project just wiring up "boring" infrastructure like Authentication, Team Invites, and Billing webhooks.

I decided to open-source my internal kit (MIT Licensed) to fix this.

The Goal: Help founders skip the plumbing and start building their unique business logic on Day 1.

The Stack:

Backend: Go 1.23 (Modular Monolith with sqlc).

Frontend: Next.js 15 (App Router).

Included: Pre-configured RBAC, Multi-tenancy, Billing (Polar), and a pgvector RAG pipeline.

It’s opinionated, but it saves you from "Decision Fatigue" when launching a new product. Happy to answer questions!