Here is the full list of all 15 Circuits achievements. It takes around 5-6 hours to unlock all of the achievements on Windows.
Build 5 levels
Use the turbo for more than 6 seconds
Complete the first three levels without any fail
Build level 2 in less than 4 minutes
Build all levels without switching to individual layers, with the level 3 exception.
Build 10 levels
Build 15 levels
Build 20 levels
Build 25 levels
Build 10 levels without using hints
Put the level 10 loopers correctly with the first check
Read the credits after complete the game
Build correctly your first Looper
Skip more than five levels
Build the level 16 switcher in the correct way for the first check