The Valve Developer Union was a stab at a modern-day Valve Editing Resource Center, archiving tools and writing guides about mapping for various Quake-based engines, including Valve's GoldSrc and Source engines. The site was launched in September 2017; by August of the following year, it was defunct, due to differences between the site's webmaster and maintainer.
This is a static archive of everything that was ever posted to the Valve Developer Union site, both tools and guides. Nothing in this section will be updated past its transfer to the new site. The direct downloads, including some for tools that didn't make it onto the site, can be found on our sister site, Conglom-O.