Deprecate Newtonsoft?

[TonyValenti]

Is it possible to use this library without newtonsoft? Id like to stick to STJ.

[AArnott]

You can use the SystemTextJsonFormatter instead of the JsonMessageFormatter to avoid Newtonsoft, yes.
I think you still need to ship Newtonsoft.Json.dll with your application, as the CLR will try to load it when doing reflection on attributes that are in this library, but it wouldn't use it for serialization.

Note that System.Text.Json support is very new (#305) so it will first release in v2.16 of this library.