Using already existing microservice in my code or implement it inside my actor?

I was wondering if a microservice like QR code generator runs faster on the IC when I implement it into my own canister? If so and I was super into perfomance, I would then probably just recode the same thing into my own canister. So does a canister on the internet computer that wants to be valuable to other people need to implement some sort of “extra” value, like the linkedup example social graph not only being a social graph, but the social graph for all social applications build on the IC. @enzo