For the test_app_server to run properly on Haiku, you need to prepare a few things.

There is a pseudo target "install-test-apps" which needs to be built like this:

$ TARGET_PLATFORM=libbe_test jam install-test-apps

This will build "test_registrar", "test_app_server", the needed libs and some test apps and install everything into "generated/tests/apps".

You can use the "run" script in this folder to run the servers, as well as open the test app folder in Tracker (via the -o option), or launch specific test app(s) by specifying their name in the command line, for example "run WindowInvalidation".

Have fun!