After a beta period of almost a year we have removed the "beta" label from our Sinatra support, making it a first class citizen among the frameworks AppSignal officially supports.
All of our error tracking and performance monitoring features work out of the box, plus all of the third party integrations. Because all data is shown in a standardized format, there is no mental overhead when switching between your Rails and Sinatra apps within AppSignal.
We pick up on the endpoints you define in your Sinatra app and group all information we display based on this:
Our Sinatra support is already being used by Bundler to monitor the Bundler API, which handles 3,000 requests per minute across 10 hosts. We're most thankful for their vote of confidence and feedback (special thanks to André Medeiros).
Please see the documentation on Sinatra support to get more information on how to easilly install AppSignal for your Sinatra app. Enjoy, and if you have any feedback: let us know. We're happy to help.