Here is the full list of all 21 MewnBase achievements.
Research 1 Artifact
Complete your artifact research log
Unlock 1 tech upgrades
Unlock 5 tech upgrades
Unlock all tech upgrades
Build a buggie!
Construct a Habitat Module
Construct your 100th Habitat Modules
Collect 10 plants grown in a Garden Patch or Greenhouse
Complete your first mission
Complete 10 missions
Complete a Long Night mission
Complete an Only Night mission
Repair 100 air leaks
Survive for 25 days
Survive for 50 days
Collect 250 plants grown in a Garden Patch or Greenhouse
Have a base that generates over 200 power/sec
Have a base that has over 1000 water stored
Craft 500 metal plates
Research 100 artifacts