The Ruby Gem for Bittrex is a library for interfacing the Bittrex API with an existing Ruby application. The library is open source, however, the Bittrex API requires an API key for use. The library is not officially owned by Bittrex, though it's usage is endorsed by Bittrex on their API documentation page.
Wicket Labs has come out of months of beta testing with its API monitoring and reporting product. The tool is designed to proactively catch API issues before issues lead to downtime in apps, sites, and systems. The live reports, called wickets, include easy to understand, color-coded scorecards.