We are glad to inform you that from today you can use Dota 2 Workshop Tools. It will help you for example create and share custom maps for Dota 2. Unfortunately, it has high system requirements (64-but version of Windows and a Direct3D 11 compatible GPU), but the team is working on reducing them.
What's more, you can expect by the end of August Compendium Stretch Goals prepared by the Dota 2 Team. Stay tuned!