# Day 1: Overview (Whiteboard) ```bash app.cpp # actual code config.proto # configuration proto message CMakeLists.txt # build instructions ``` Single Thread: `goby::zeromq::SingleThreadApplication<typename Config>` Multi Thread: `goby::zeromq::MultiThreadApplication<typename Config>` Configurator: - goes from the command line parameters -> Config object optional `loop()` method Configuration is accessible via `cfg()` method in the parent class. ```bash goby3_course_my_app --value_a 3 -v ``` --- ``` ```