Consider implementing a hook to inject a configured Raygun client instance

[girtsl]

Please take a look at this question on StackOverflow.
I'm not sure how well this aligns with log4net design principles, but using the same approach I was able to put together a log4net.raygun implementation that would obtain an instance of Raygun client configured by the host application.
The pros for such feature include but are not limited to: taking advantage of Raygun's means of configuration, smaller memory footprint.

If you consider this feature worth adding to the project, please also consider changing the raygun message building logic - the log4net.Raygun.RaygunMessageBuilder implementation is currently dettached from the RaygunClient (or log4net.Raygun.Core.IRaygunClient) instance and does not use the property values set on it - ApplicationVersion to name one.

[plmwong]

Added in a configuration property on the appender which can be pointed to an implementation of IRaygunClientFactory. This gives developers control over the construction of RaygunClients used by the appender, including just having a factory which points to an instance (e.g. RaygunClientFactoryMethod.From(() => _preconfiguredInstance).

This has been merged into release 4.2.0.