Need dev help: Implementing crypto payments on server and client

Im building a robust javascript library and i want to be able to create (Javascript) clientside web wallets as well as serverside NodeJS wallets.

In my ideal world, id implement both JS client/server on XMR, BTC, and BCH.

Ive struggled doing it for Monero thus far, so in the interest of making progress, are there any good repositories where I could implement crypto payments on the server and/or client, for BTC and/or BCH? Id even do it for Nano or whatever, i just want to make some kind of progress.

Features I am desiring: 1) Dont need to run a node, 2) make wallets, 3) receive coins, and 4) spend coins. And id prefer a solution that does not require me to webpack/minify my library code (so if theres some way to compile the repo in a way to expose the namespace for my library, i want that solution.)