This is related to a change in json 2.3.0 and has been reported upstream: https://github.com/getsentry/raven-ruby/issues/947
Possible fixes are discussed here: https://github.com/getsentry/raven-ruby/pull/952 https://github.com/getsentry/raven-ruby/pull/946 Seems upstream went with disabling/removing the test. So we can do the same. Regards, Daniel
