Developer Mode removed
The Ruby Agent's Developer Mode, which provided a very limited view of your application performance data, has been removed. For more information, check out our community forum.
Support NEW_RELIC_ENV for Rails apps
Previously, users could set the agent environment with NEW_RELIC_ENV only for non-Rails apps. For Rails app, the agent environment would use whatever the Rails environment was set to. Now, NEW_RELIC_ENV can also be used for Rails apps, so that it is possible to have an agent environment that is different from the Rails environment. Thanks Andrea Campolonghi for the contribution, as well as Steve Schwartz for also looking into this issue!
Normalization of external hostnames
Hostnames from URIs used in external HTTP requests are now always downcased to prevent duplicate metrics when only case is different.