Option to compile epicscorelibs single-process for low memory machines?

[klenze]

I tried to install softioc on a raspi3 (1GiB) with pip3 as recommended, but the setup system insists on using four processes in parallel, which will then slow down to a crawl when four g++ instances manage to eat all available memory.

Is there a good way to tell pip/setuptools to only use a single thread, like make -j1 would?

I tried pip with --install-option="--jobs=1" but then it does not compile at all.

Or would the recommended way be to compile EPICS manually and then have the softioc autodetect that installation?

Sorry if this question is off topic.