Forward Payment Altcoind

[danystatic]

We've got many Altcoins now.

Can some one share a me a clue (or link to a github repo) regarding how a Forwad Payment service could be Built?
Best Example:   www.BlockCypher.com they have a free tier for forward payments with Bitcoin.

Works with Bitcoin.
But watch out, they did not forwarded my Litecoin !!     

What can I expect from a free service?