Because there does not seem to be an "in development" category, how can I list all of GoG's in development games ?

When searching for games via the Games tab, click "Features" and then click "In Development".

There's a pulldown menu for this :

https://www.gog.com/games?feature=in_development&sort=title&page=1

wasn't fast enough :)

"In Development" is listed as a search filter under "Features".

Thank you all wonderful GoG people.

I just wanted to see how many of the total indevelopment games I have............not that many as many are quite expensive really.

In developent is one of the best things GoG ever did I say, well bar DRM free which is the MOST important thing. :)