Found the error myself, it was due to a typo in test.c file
The above tree tutorial can be used to create a new component, if people are searching for that, this is working!
Joel

Hello all ! I'm new to the forum and already browse it, found similar issues but didn't succeed to find a solution in my case... I'm using an ESP-32 and try to make a custom component. I'm not able to build it, I have a linker error... here is my project tree: project --components ----test ------inc...