You will need make, clang and lldb installed.
These are present by default on macOS, and on Ubuntu can be installed with
sudo apt install clang lldb.
# Check `make`, `clang` and `lldb` are installed
make check
# To build and run `src/main.c`
make run
# To run the tests in `src/test.c`
make test
# To start `src/main.c` in the debugger
make debug
# To start `src/test.c` in the debugger
make debug-test