currency-rates | A fetching currency rates | Runtime Evironment library

Forgive me for these heretical speeches, but I consider express to be the best library for api building from the developer experience point of view. But what stops me from using it everywhere is that everyone keeps saying (and confirming with benchmarks) that it is slow.

I try to choose an alternative for myself, but I canэt find what suits me.

For example with express I can simply organize the following structure:
userAuthMiddleware.js

Everytime i try to delcare my provider into the .ts file's constructor i get the following error when running my app. https://imgur.com/a/pRn9lrJ

here is my TS File and the corresponding html file with the provider's ts file too. It seems to be okay after just importing the provider into the ts File but whenever i enter in the provider into the constructor i get that error. Something about the HTTP Client, but I dont remember ever creating a provider for HTTP Client in class so I'm unsure how to proceed.

TS