@Anco-van-der-Kolk The general principle for compiling for the Omega is very simple. You first write your program in C/C++. You will have access to all of the linux system calls, and you will be able to use most libraries out there (except for ones that are very architecture dependent). Once the program works, you need to write a makefile that tells the compiler how to compile the program which you have just written. Then, you will be copying the makefile to the Linux buildroot, and you will be able to compile your program either as a opkg package or directly into the firmware.
For more information, please take a look at this article: https://wiki.openwrt.org/doc/devel/packages.