The modern typed framework.
WHAT IT PROVIDES
Routing Validation and serialisation from type declarations Automatic interactive documentation Asynchronous handling Dependency injection
WHAT THE TYPE DECLARATIONS DO
Define the expected shape of requests and responses.
WHAT THAT PRODUCES AUTOMATICALLY
Validation Clear error messages An API specification Documentation
WHY THAT MATTERS
Documentation and validation stay consistent with the code, because they are derived from it.
WHAT IT SUITS
APIs, particularly Services with many external callers Work benefiting from asynchronous handling
WHAT TO BE CAREFUL WITH
Mixing synchronous blocking calls into asynchronous handlers
WHY
It blocks the event loop, stalling every request.
WHAT TO DO ABOUT BLOCKING LIBRARIES
Use asynchronous equivalents, or run them in a thread pool.
WHAT TO DEFINE
Separate models for input and output.
WHY
So internal fields are not exposed, and inputs cannot set fields they should not.
WHAT TO CONFIGURE
Whether documentation is publicly available.
WHAT TO RUN IN PRODUCTION
An appropriate server, with several workers.
