I Built a Self-Hosted License Key Manager in One Evening — Here's the Code and the Monetization Plan

Lemon Squeezy charges $29/month to validate license keys. $348 a year for what is basically a key-value lookup. I got annoyed enough to build my own.
KeyMint is a self-hosted license key manager for people selling digital products on Gumroad or anywhere else. You generate keys, set activation limits, and validate through one API endpoint. Buyer's app hits the endpoint on launch, gets a valid/invalid response. That's it.
React 19, Express 5, PostgreSQL, Drizzle ORM. Cloudflare Pages for the frontend, Railway for the API, Neon for the database. Monthly hosting cost is zero.
The deploy was not clean. Railway's free tier had hit its project limit so I had to add KeyMint as a new service inside an existing project instead of creating a fresh one. Then the esbuild bundle crashed silently on boot because pg wasn't listed as a direct dependency of the API package — took a while to figure out. And Cloudflare has two deploy flows, Workers and Pages, and the Workers one is completely wrong for this setup. Pages GUI only.
Live demo: keymint.pages.dev — already has seed data so it's not an empty screen.
Source code: gumroad.com/l/nvkfg — $49, MIT licensed.
Four boilerplates shipped this month, zero sales across all of them. I think it's a distribution problem but honestly I'm not sure yet. Reddit and dev.to are next.
Anyone here sold source code or boilerplates before? What actually moved the needle for the first sale?