If you don't use the SDK, or want to use a specific version, the following packages are of interest:
# axunitst packages
apax add @ax/axunitst -D;
apax add @ax/axunitst-ls-contrib -D;
# sdk packages
apax add @ax/stc -D;
apax add @ax/apax-build -D;
apax add @ax/target-llvm -D;
# run on a plc/ plcsim
apax add @ax/target-mc7plus -D;
apax add @ax/sdb -D;
apax add @ax/sld -D;
apax add @ax/mon -D;