Zap Aliases

This morning I figured out something neat that I'm calling zap aliases.  (Thanks for the name @cypher)

A zap alias maps to a zap address (lud16). For example: sats sent to the lightning address sat@bolverker.com arrive in my bolverker@strike.army lightning address and are available in my Strike account.  If you have a lightning address hosted by a third party like walletofsatoshi.com, strike.army, or getalby.com and you want to have a lightning address which uses your own domain without having to do the all heavy lifting then a few simple steps will get you going with you own zap alias.

To do this you need some sysadmin skills, a domain that you own, the ability to create dns records for your domain, and an nginx install.

There are three tasks:

1) Get your third party payment descriptor. 

"Given the Lightning Address:

satoshi@example.com

That means under the current specification, the payment descriptor will be located at:

https://example.com/.well-known/lnurlp/satoshi/" 

- bitcoinmagazine.com/technical/simplifying-bitcoin-addresses-dns

What?

If satoshi used getably.com for his lightning address, satoshi@getalby.com, then his payment descriptor would be at: 

https://getalby.com/.well-known/lnurlp/satoshi

If he used walletofsatoshi for an address of satoshi@walletofsatoshi.com it would be:

https://www.walletofsatoshi.com/.well-known/lnurlp/satoshi

Generally speaking yourusername@yourthirdpartylightningaddress.com becomes:  https://yourthirdpartylightningaddress.com/.well-known/lnurlp/yourusername.  You can test this by pulling up the payment descriptor up in a web browser you'll see the corresponding json for your address.

2) Set a dns txt record  for your zap alias.

yourusername@yourdomain.com looks like:

Host: _lud16.username.yourdomain.com.	Text: https://yourdomain.com/.well-known/lnurlp/username

For sat@bolverker.com my record looks like:

Host: _lud16.sat.bolverker.com.	Text: https://bolverker.com.com/.well-known/lnurlp/sat


3) nginx config. 

In the default sites-enabled, or yourdomain.com vhost config, add a location with the payment descriptor you got in step 1.

yourusername@yourdomain.com looks like:

location /.well-known/lnurlp/yourusername {
   proxy_pass https://yourthirdpartylightningaddress.com/.well-known/lnurlp/yourusername;
}

For satoshi@getably.com it would look like:

location /.well-known/lnurlp/satoshi {
   proxy_pass https://getalby.com/.well-known/lnurlp/satoshi;
}



Test your nginx config and reload.
              
That's all that's required for a zap alias.