Celerbrake Ruby is a plain Ruby notifier for Celerbrake (https://celerbrake.com), a cloud-based, wire-compatible error-tracking service. It provides a minimalist API for sending any Ruby exception to a Celerbrake dashboard. The library is extremely lightweight and suits plain Ruby applications well. For apps built with Rails, Sinatra or any other Rack-compliant framework we offer the celerbrake gem (https://github.com/celerbrake/celerbrake), which reports unhandled exceptions automatically and integrates with Resque, Sidekiq, Delayed Job and many more. Celerbrake Ruby began as a fork of airbrake-ruby (https://github.com/airbrake/airbrake-ruby) and remains wire-compatible with the Airbrake v3 notice API; the default host points at Celerbrake rather than a third-party service.