Hobbyist coders who are eager to get started might find it useful to start getting familiar with MediaWiki:

https://www.mediawiki.org/wiki/How_to_become_a_MediaWiki_hacker

and set up their own bleeding-edge MediaWiki installations:

https://www.mediawiki.org/wiki/Download_from_Git

Other Wikimedia technology projects that you might want to get familiar with:

https://meta.wikimedia.org/wiki/Developer_hub

Hope this helps!