Techland plans to do a general public release of its Dying Light development tools in the near future, but for now the studio is going to run a closed beta session.
Details on how to sign up are included in this announcement post on the Dying Light Steam hub. Basically, you need to send an email to firstname.lastname@example.org and mention your Steam ID. That seems to be it. Nice and simple.
If you’re accepted, you’ll be one of the first to use the dev tools to make new things for Dying Light. Techland stress that because the dev tools will be in an early state, people should “be prepared to come across some difficulties.” However, part of the point in running a closed beta is to expose those difficulties and receive ideas on how to improve the tools.
As for when the dev tools will be available for all, Techland say “We’ll be releasing them soon.” That ‘soon’ might depend on how well the closed beta session goes, I presume.
After a slightly rough start with the modding community, during which there were some unfortunate copyright-related take downs of simple Film Grain removal mods (possibly from publisher Warner Bros. end of things,) Techland look to have committed pretty heavily to community involvement in the game.