Usually there's no need to build userver itself. Refer to Configure, Build and Install section to make a service from a template and build it.
If there's a strong need to build the userver and run its tests, then:
ulimit -n 4096 && ctest -V
Alternatively you could use a docker container with all the build dependencies installed from Configure, Build and Install
If you need to edit or make your own docker image with custom configuration, read about it at Building Docker container for userver.
Thanks to Open-Source community we have Conan support.
You must run the following in the userver directory:
Make sure to pass flags corresponding to the desired userver libraries, e.g. --with_grpc=1
Now you can use userver as conan package and build it in your services: