Here is the full list of all 10 NCradle: An 80s Synth Adventure achievements.
Complete Levels 1-10 in a perfect run
Complete Levels 31-40 in a perfect run
Complete a stage after your last node has been destroyed
Complete Levels 41-50 in a perfect run
Complete Levels 21-30 in a perfect run
Complete Levels 11-20 in a perfect run
Complete a level after destroying a program node
Access all 6 hidden levels