Thank you. I use a layout for each project I work with which keeps a nice separation of actions between projects. I think I have about 20 layouts at the moment. I can easily switch between current and last project with SPC l TAB and switch between buffers of the current project with SPC TAB TIP: if you have lots of layouts and each layout has lots of buffers (or a huge buffer like the spacemacs changelog.md) then this does slow the startup of Spacemacs a little as it opens all these buffers (although I rarely have to restart Emacs)

This is seriously cool. I didn't understand what it tries to achieve at first but after fiddling with it I understood. What it does is it allows to save window states (and sizes, positioning and so on) so that if you want to run tests for one part of the project then you can do it in one layout. And if you want to edit a diagram and see it side by side then you can have one more layout where you have your diagram files open in the sizes that you prefer. This is great!