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Document Q&A, packaged as a product anyone can buy

Client My own productRole Everything. Product, engineering, pricing, billing.Period 2026

The problem

Plenty of teams have the same problem: a pile of documents nobody can search properly, and the answer buried somewhere inside them. Most of them do not want a consulting engagement. They want the thing to already exist.

Building it once for one client solves it once. Packaging it means the same work keeps paying, and a buyer can try it before ever speaking to me.

What I built

  • A live public demo that answers questions against sample documents with no signup, so a buyer can judge the quality in about thirty seconds.
  • Answers with citations that point back to the exact passage, plus a confidence signal, because an answer you cannot check is not worth much.
  • Self serve billing through Stripe: checkout, webhook provisioning, an API key minted and emailed automatically, no human in the loop.
  • Per account quotas and per visitor rate limits enforced atomically in the database, so usage cannot be exceeded under concurrency and a free public demo cannot run up an unbounded inference bill.

The hard part

The commercial plumbing, not the AI. Retrieval is a known pattern. Making a stranger's payment turn into a working API key with no human involved, and making sure a free public demo cannot be abused into a large bill, is where the real engineering went.

Outcome

Live and buyable

Try it, subscribe, get a key, no email needed

Cited answers

Every claim points back to its source passage

Cost controlled

Quotas and spend ceilings enforced in the database

Stack

Next.jsTypeScriptOpenAIpgvectorPostgreSQLStripe

This one is live

Document Q&A with Citations

Ask contracts, policies, and reports in plain English. Every answer cites the exact source passage.

Try it and see pricing

Have a similar problem?

Thirty minutes, no pitch. If this isn't the right approach for you, I'll say so.