I’ve published my rust BTCPay and LNbits webhook library with example projects for each platform. The code is really simple to follow.
This means when invoices are paid, you can trigger actions, like updating a database to grant access to a pubkey (like a paywall), add credits to an account, sending a Nostr message, or whatever. It performs the HMAC validation for BTCPay server payloads.
I’m not using it yet myself, as I need to finish my Nostr Paywall Server project first - which I’ll release this week. Let me know if you’re keen to use it in production or any other features needed.