This is more of an experience than a game in a traditional sense. You can't lose, but you get points depending on how well you play. The less mistakes you make the more points you get.
There is no time limit. I experimented with adding it, but it was changing the character of the game in a way that I didn't like it. You would have to be focused on pressing right keys in the right moment. It was really hard with 18 keys, and it made the game less enjoyable. So I decided that there will be no time limit.
You can play as fast as you want. You can pour yourself and your creativity into it. Because this game is about creating something beautiful with power drills :)