Sysadmin shit, to host independent communities and servers. Not cloud BS, hosting on dedicated servers instead - from at least slightly more censorship-resistant hosts - or even home servers (greater legal risk), and load-balancing properly. High level (as in: removed from the math, not "advanced" - just get a handle on what's secure) encryption stuff, to implement secure communication that does not rely on an easy common target (custom apps potentially, including mobile apps for the zoomers - even if they're mostly just a chat frondend to GPG; I recommend user-enabled NFC key sharing if you go this route - tap a few buttons, put your smartphone against a comrade's phone, boom, trusted key exchange - do not trust smartphones for anything too critical though, and the same applies to windows computers or linux ones without proper full-disk encryption). Webshit stuff, to publish content and try and inform people (though mind you on that one wordpress would almost universally do the job). Cybersecurity stuff, finally, for data extraction and hacktivism and the like - auditing code (or fuzztesting proprietary binaries) for flaws; not publishing them straight out and exploiting them to disrupt shit or at the very least diffuse a message.