This plugin has been deprecated and will no longer work after April 30th, 2018. This plugin previously allowed merchants to accept Bitcoin on your Spree-powered website with Coinbase legacy merchant tools.
Coinbase Commerce is a new merchant payment processor that allows you to accept multiple cryptocurrencies.
Archived plugin here: https://github.com/coinbase/coinbase-spree/blob/master/coinbase-spree.zip