To reproduce: ``` python workspace_tools/build.py -m K64F -t GCC_ARM --rtos python workspace_tools/project.py -m K64F -i uvision5 -n RTOS_1 ``` You will see that there is no built RTOS library included, just header files. If I repeat with the following: ``` python workspace_tools/build.py -m K64F -t ARM --rtos python workspace_tools/project.py -m K64F -i uvision5 -n RTOS_1 ``` The built RTOS library is included along with the header files. In the first case, I would expect this to error with something along the lines of: ``` Library 'RTOS' was not found, please build with toolchain 'ARM' ``` OR it should just build it for you :) cc @0xc0170