Internal infrastructure · 2026
billing-kit
A reusable payments and referral layer so every app I ship can start charging in an afternoon instead of a fortnight.
What it is
A drop in package that gives any of my Next.js apps checkout, webhooks, an entitlements table, a paywall component, and an affiliate referral program. One Lemon Squeezy account and one Supabase table serve every app. Each new app wires three routes and is done.
Why I built it
I noticed I was rebuilding the same two weeks of work every time a side project got far enough to charge money, and that those two weeks were exactly where most of my projects quietly died. Removing that friction is worth more than any individual feature in any individual app.
Lemon Squeezy is the merchant of record, which means it handles global sales tax and VAT and the affiliate payouts. For a solo builder selling to strangers in forty countries, that is not a convenience, it is the only sane option.
How it works
Checkout goes to a hosted page, the webhook comes back signature verified, entitlements land in a shared table, and the paywall reads from it. Shipped as TypeScript source consumed through Next's transpilePackages, so there is no build step and no publishing dance when I change something.
Where it stands
In use. It is the least glamorous thing on this page and probably the highest leverage.