// the take
Quill is a reference SaaS implementation — a PDF-chat app with auth, billing, and RAG built on Next.js 13 App Router, tRPC, and Prisma. It's a companion repo to a paid coding course (joshtriedcoding), aimed at developers who want a working example of how auth, Stripe billing, file upload, and LLM chat plug together, not a library to depend on.
Shows a full vertical slice end to end: Kinde auth, Stripe subscriptions with webhook handling, UploadThing file upload, PDF rendering, and a LangChain+Pinecone RAG pipeline with streaming responses — useful as a wiring reference rather than toy snippets. Type safety runs the whole stack via tRPC + Zod validators, so client and server share types without a REST layer. The infinite-scroll query config and optimistic UI updates in the chat components are patterns worth stealing even if you don't use the rest of the repo.
No test directory anywhere — a billing and auth flow with zero test coverage is a bad thing to fork as a 'complete SaaS' starting point. Last pushed May 2024; it's pinned to Next.js 13.5 and specific versions of Kinde, UploadThing, and LangChain that have all moved on, so expect dependency upgrade pain before this runs cleanly. Every integration (Kinde, Pinecone, UploadThing, Stripe) is hardcoded with no abstraction, so replacing any one vendor means rewriting integration code, not changing config. It's a course artifact, not a maintained project — the README links back to the author's paid course, and there's no indication issues or PRs get attention.
We read the README, the directory tree and a key source file in October 2026. Nobody pays to be listed. How we judge →