At the moment, the only type of mods supported are language/translation mods. You can drop a few JSON files in this directory: %USERPROFILE%\Documents\Tech Giants\Mod, and then enable the mod in-game.
I have been experimenting with mods to allow players to add more content or customize platforms, features, and other aspects. I will write a more detailed devlog when it’s ready and can do more than just handle language and translations.