Here is the full list of all 24 Spaceport Hope achievements. It takes around 8-10 hours to unlock all of the achievements on Windows.
Visit the about menu
Kill an enemy
Kill 100 enemies
Collect 1000 coins
Buy a weapon
Find a chest
Find the island
Die 50 times
Kill 500 enemies
Collect 10000 coins
Unlock all the weapons
Find 10 chests
Go underwater
Explore all the world
Find the hacker hideout
Complete all the NPC quests
Talk to all NPCs
Update your main weapon
Unlock a new outfit
Buy a new ship
Assemble the ultimate weapon
Beat the final boss
Beat the final boss with only the 1st gun
Die in the tutorial level