The one case I can make for implicit conversions (implicit parameters are brilliant and useful and not normally what people complain about) is the spray-routing DSL, e.g. https://github.com/spray/spray/blob/master/examples/spray-ro... . What would be a separate config file in any other framework is instead ordinary Scala code following the rules of ordinary Scala, which is wonderful - you can factor out and reuse common parts of your routing really easily, because it's all just code.