Batch Compile Tool
From Valve Developer Community
This tool allows you to compile Source .VMF maps while outside of Hammer and without slowing down the computer. It makes compiling a breeze and you can edit maps or use your computer at the same time.
The latest version of the program is version 1.0u BETA, released 06 July 2013 to support the new STEAM changes which moved all the games over to the "common" folder.
This version also now supports ALL Valve game MODs including: Half-Life 2 Half-Life 2: Episode One Half-Life 2: Episode Two Left 4 Dead Left 4 Dead 2 Left 4 Dead 2 BETA Portal Portal 2 Alien Swarm Counter-Strike: Global Offensive Counter-Strike: Source Day of Defeat: Source Team Fortress 2 Half-Life 2: Deathmatch and partially: Half-Life Deathmatch: Source