RegKit - one-step signup + payment for Next.js, FastAPI, and dotnet
Most SaaS products default to one of two signup flows. Both introduce friction that kills conversions.
Option A: Stripe Checkout, then a magic link. Payment works, but you've just sent someone to check their inbox at the exact moment they're most engaged.
Option B: Sign up, then pay. Now you've got unverified accounts, a reconciliation problem, and a conversion moment that can fall apart.
I posted about this problem a few months ago in the Developers group. Turns out everyone has hit this wall. One comment stuck with me: "The main thing is making sure retries and failures don't create duplicate users or charges — that's where it tends to get messy."
So I built the fix.
RegKit handles the correct flow out of the box — one form, one submit, payment confirmed server-side, account created, user is in. No second step, no inbox detour.
It covers the parts that actually bite you in production — server-side PaymentIntent verification, webhook fallback for dropped connections, idempotency, and async payment methods like Klarna and ACH.
Drop-in for Next.js, FastAPI, and dotnet.
Early Access — $99 for the first 100 customers, then $199.
Would love feedback from anyone who's wrestled with this flow before.
I know a few developers who have built signup and payment flows for SaaS products, and they'd probably be open to answering some questions for free. Let me know if you want me to pass them along.
Hi Greg,
Really like how you focused on the exact moment where conversions break — the “inbox detour” problem is something most SaaS flows still get wrong.
Out of curiosity, have you considered enabling other builders or agencies to help distribute RegKit and earn from the customers they bring, instead of relying mainly on direct outreach and posts?
Thanks! Definitely something I'd consider — the audience is developers so there's a natural fit for technical bloggers and newsletters. I might revisit once I have some early customers and can see what's converting.
Appreciate that — makes total sense to validate what’s converting first.
One thing we’ve seen though is that even early users (like dev bloggers or small agencies) can double as both users and distribution at the same time, especially in dev tools.
Happy to share a simple way to test that without adding much overhead, if helpful.