This page seems to only focus developers (apart from a "Translation" section). Hence its scope is already covered by How to become a MediaWiki hacker (developers) and How to contribute (general). Hence I propose to move any potential unique content from this page to one of these two pages and delete this page, after checking "what links here". (Obviously I believe that we have too many pages targetting 'starters'.) Comments?
(Explicitly pinging @Qgil-WMF as the original author.)