Electrum, one of the most popular desktop Bitcoin wallets, has a server component which can use your Bitcoin public keys on a web server to process transactions

Electrum, one of the most popular desktop Bitcoin wallets, has a server component which can use your Bitcoin public keys on a web server to process transactions. It generates a verified request for payment in BTC using your existing SSL keys. Bitcoin still is the most ubiquitous for payments, even from Ethereum (e.g. via renBTC) but the transaction fees are still prohibitive for smaller sums less than $20 unless you involve Lightning network which may become much less turnkey. https://electrum.readthedocs.io/en/latest/merchant.html https://electrum.readthedocs.io/en/latest/merchant.html