Look into LNbits LNPoS offline terminal

• https://github.com/lnbits/lnbits/wiki/Tooling-&-Building-with-LNbits#lnpos-terminal

And with LNbits you can do much more things as a merchant (even being a LN bank for your customers). Here I wrote several guides:

• https://darthcoin.substack.com/p/getting-started-lnbits
• https://darthcoin.substack.com/p/lnbits-for-small-merchants
• https://darthcoin.substack.com/p/bitcoin-private-banks-over-lightning
• https://darthcoin.substack.com/p/lnbits-nostr-market
• https://darthcoin.substack.com/p/lnbits-saas-a-solution-for-schools
• https://darthcoin.substack.com/p/build-your-own-lnbits-app-server
• https://darthcoin.substack.com/p/the-bank-of-lnbits
• https://darthcoin.substack.com/p/lnbits-streamer-copilot