I'm setting up DD APM to trace a Rack -> Sinatra -> Postgres application

With the following configuration each of these layers are presented as a seperate service in the environment. Which seems to be the way DD is expecting to be setup.

  Datadog.configure do |c|
    c.tracer(
      hostname: ENV.fetch('DD_AGENT_SERVICE_HOST'),
      port: ENV.fetch('DD_AGENT_SERVICE_PORT'),
      env: ENV.fetch('DD_APM_ENV')
    )
    c.use :rack
    c.use :sinatra 
    c.use :sequel
  end

  use Datadog::Contrib::Rack::TraceMiddleware

However the rack service is grouping requests by http method and response code

Whilst the Sinatra service is working as expected:

From reading through the code it seems like the Sinatra integration should be setting the resource on the rack span or am I missing something?