I'm not sure but they seem to be focused on the client side: creating transactions, signing, getting transaction history, SPV, etc. Everything you need if you are connecting to a bitcoin core instance.
On looking (slightly) closer, Haskoin seems to be SPV; harder to tell with Purecoin; and besides, "full" is ill-defined so I guess it doesn't matter too much.
Anyway, it's interesting to see another functional approach; I like the brevity and your walkthrough especially. Thanks for sharing!
