Include the gem in your gemfile and use bundler to install your dependencies.
gem 'nexosis_api', '>= 2.0.0'
NexosisApi class exposes the client as a class method. The client will be cached across uses so you can initalize it once with the API Key:
require 'nexosis_api' NexosisApi.client(:api_key => 'your key here')
In most cases you’ll want to load the key as a secret or from the environment so as not to expose it in your source code.
Once you have the client initialized you can call again without specifying the key
balance = NexosisApi.client.get_account_balance
If you run into issues using this client library, create a new issue in github. Please include code to reproduce the error if possible.