Valve Developer Repository Leaked: Over 60 GB of Unreleased TF2 Content Has Just Gone Public | Attack of the Fanboy
SDK Docs - Valve Developer Community
Valve Developer Community | ВКонтакте
Warning: Reports that the Valve Developer website (hosts Source SDK Wiki etc.) has been hacked, serving malware files to users. : r/HalfLife
Valve still working on single-player games — and those Half-Life and Portal movies - Polygon
Steam Community :: Guide :: How to Properly Ask a Source Engine Question
CS:GO Developer Explains Why Valve Rarely Communicates With the Community
Hammer - Setting up - YouTube
wickedplayer494 on Twitter: "A lot of Valve employees are fed up with scammers attempting to impersonate them (mainly off of the Steam platform entirely), so much so that numerous (but not all)