Hello,
Custom levels now can be shared in Steam Workshop. ːsteamhappyː
I've added a dedicated window for Custom Levels to separate them into:
Official levels (shipped with the game)
Local levels (in the filesystem of the user) and
Subscribed levels (from the workshop).
You can create a folder by level into the local_folders/ folder in the game path with a description file (desc.txt) plus a lua kernel file (kernel.lua) very similar to the custom levels that were loadable by file. These levels in folders can be published to the workshop.
I've added an "open folder" button that opens the filesystem containing that specific levels, so it's easy for people to inspect how other levels work (or edit his own level).
The levels are all sandboxed on lua, with exception of the levels loaded "by direct lua file" as was before, those ones bypass the lua sandbox and can do stuff like load and write from the filesystem for those who want to.
It's a bit "bare bones" right now, will iterate with time. Among the examples there's one "combinational" template and 2 "variable clock cycles" level, for more complicated problems, but the API should allow for more types of levels.
It's true also that the metric calculations need to be reworked too to make levels more exciting, I was thinking of something like "Ticks per cycle" + max cycle tick + cycle number instead of global ticks and something similar for energy.
Please don't hesitate to share what you think and if you have more ideas on how to improve or ideas for levels.
Have fun!