At its core, tapir creates a data structure describing the HTTP endpoints. This data structure can be freely interpreted also by code not included in the library. Below is a list of projects, which provide tapir interpreters.
Caliban allows you to easily turn your Tapir endpoints into a GraphQL API. More details in the documentation.
tapir-gen extends tapir to do client code generation. The goal is to auto-generate clients in multiple-languages with multiple libraries.
scala-opentracing contains a module which provides a small integration layer that allows you to create traced http endpoints from tapir Endpoint definitions.