Another thing I added was the ability to set the price dynamically in the query string:

https://tls.lnlink.org/?d=ASED88EIzNU2uFJoQfClxYISu55lhKHrSTCA58HMNPgtrXECcHJveHkubG5saW5rLm9yZy9tb25hZC5lbmRwb2ludC5qYjU1LmNvbQADYAego9kAnmQBTmdZ0uqhrkXuFX-qs8CckOUKN29B0bf8PTEyMCZtZXRob2Q9aW52b2ljZXxtZXRob2Q9d2FpdGludm9pY2UmcG5hbWVsYWJlbF5sbmxpbmstJnJhdGU9OARCcmVhdGggIFN0YXIABkFuIG9iamVjdCBvZiB1bmZhdGhvbWFibGUgcG93ZXIuIFBsZWFzZSBlbnRlciB5b3VyIGFkZHJlc3MgZm9yIGRlbGl2ZXJ5LgAHAQhodHRwczovL3VwbG9hZC53aWtpbWVkaWEub3JnL3dpa2lwZWRpYS9lbi9mL2Y5L0RlYXRoX3N0YXIxLnBuZwAKAAAnEA==&fiat=123456

So that the shopify template email can pass this to adjust for shipping, etc