Here is the full list of all 48 Space Pirates and Zombies achievements. It takes around 100-120 hours to unlock all of the achievements on Windows.
Collect 2,500 Goons
Destroy a Tier 3 UTA Base
Destroy a Tier 3 CIV Base
Retire a Specialist
Upgrade the Clockwork
Collect an Elite Specialist
Collect an Uncommon Specialist
Collect a Common Specialist
Space 250 Goons
Mass Retreat 5 Times
Explore 10 Star Systems
Train a Specialist to Expert
Destroy 500 Enemy Ships
Bribe Star Relations 5 Times
Collect 10,000 Rez
Complete 25 Missions
Collect 250 Goons
Reach Tech Level 10
Collect a Godlike Specialist
Feed Santa so much milk and cookies, that an elf falls off his sleigh
Escape the Sol System
Destroy 100 Enemy Ships
Collect 1,000 Rez
Complete 5 Missions
Repair the Clockwork
Destroy 2500 Enemy Ships
Collect 100,000 Rez
Collect 25,000 Goons
Destroy 25 Starbases
Explore 50 Star Systems
Explore 150 Star Systems
Complete 100 Missions
Collect a Rare Specialist
Bribe Past 5 Warpgates
Reach Tech Level 50
Reach Tech Level 100
Research a Category to Level 10
Unlock All Ship Hulls
Unlock All Components
The Clockwork II
Complete the Game
Complete the Game on Expert
Complete the Game on Insane
Never use Respec
Beat a Warpgate 10 levels higher than you
Clear all zombie infection
Beat all 10 arena ladders and all 5 tiers on bronze, silver and gold level. Be the champ of 150 events..
Defeat a Tier 3 Bounty Hunter Stronghold in Chapter 4. In short, do the impossible. You have our sympathy.