Here is the full list of all 42 Gunpoint achievements. It takes around 6-8 hours to unlock all of the achievements on Windows.
Catch a guilty man at the expense of freeing an innocent one.
Mock the chief of police at a critical moment.
Tell Gessler that Rooke's hired you to betray him.
Chicken out of telling Katie the truth at the last minute.
Voluntarily tell Katie the truth.
Notice the story doesn't necessarily gel with the mechanics. Become qualified games journalist.
Knock Fritz Gessler out of his office window.
Slam Fritz Gessler's office door into him.
Intimidate Fritz Gessler into surrendering.
Beat Fritz Gessler to death.
Knock Fritz Gessler out with a punch.
Defeat Gessler by rewiring his gun.
Shoot Fritz Gessler.
Use the Prankspasm to knock out someone who isn't standing near a power socket (outside of the test lab).
Complete a mission that has guards with no violence, witnesses or loud noises.
Use the Longshot to make a guard unintentionally shoot another (outside of the test lab).
Create a custom mission with at least one objective.
Publish your personalised epilogue.
Complete the game.
Kick Fritz Gessler's office door into him.
Free an innocent man at the expense of catching a guilty one.
Complete the police chief's missions without incriminating yourself.
Help justify my early, not entirely wise choice of game name by holding someone at gunpoint with the Resolver.
Get knocked down by an opening door.
Use the Crosslink to create an infinite loop that burns itself out.
Conceal your presence at the DataSec break-in from Mayfield.
Steal Gessler's technology for Rooke.
Jump into an Enforcer to knock him through a window.
Wire an elevator button to trigger something when the elevator arrives.
Use no violence at all on a mission that has guards.
Complete a mission faster than I can.
Use the Gatecrashers to kick a door through a window.
Use the Gatecrashers to kick a door into a guard.
Use the Gatecrashers to kick a door off its hinges.
Use the Hushcracker to jump through a window silently (outside of the test lab).
Use the Dropshot to land silently from a great height.
Knock a guard out by opening a door into him.
Upgrade your Bullfrog Hypertrousers to pounce instantly.
Upgrade your battery capacity to the non-figurative max.
Upgrade your Bullfrog Hypertrousers to maximum jump strength.
Leave no living witnesses to your presence on a mission that has guards.
This is an achievement in name only. No-one admires you for punching a guy that many times.