The Craftbot is a survival part that can be found in certain generated structures; See the linked list of interactive bots (doesn't exist yet).
The crafting system was first mentioned in Devlog 10. Then in Devlog 12, they said they had worked out a crafting system.
Another two Devlogs later we get our first images.
Then in 2020, we get a better look at it when YouTubers start getting access to the game.
Upgrading the craftbot gives more available spaces for crafting items and blocks.
How to obtain
You can create this bot in the mechanic's station.