You might want to look at telemetria library I wrote to simplify enabling and globally configuring telemetry in your app. It is backend-agnostic and might be used with both :telemetry and :opentelemetry backends.

usually telemetry is used for libraries, so they can expose their execution steps to the external world. while opentelemetry you gonna use on your actual application. on application side you usually just need to worry about telemetry if you want to attach to some event.

To clarify I’m referring to :opentelemetry the elixir/erlang implementation of the tracing standard.

I was wondering if :opentelemetry makes :telemetry unnecessary or if they are complementary.

Thanks this really clears it up!

So I suppose it would be considered a good practice to have code produce telemetry events (which is agnostic to how it would be consumed) and somewhere else one might forward telemetry events to opentelemetry?

Actually it seems like this is what opentelemetry_ecto is doing:

It is calling :telemetry.attach to listen to telemetry events coming from Ecto, then it translates that to a format that opentelemetry understands.

So it seems like telemetry is almost like a logging solution but a lot broader (not just text messages). It does nothing to specify how those messages are actually handled.