Derelict Fleet

Derelict Fleet is a fast-paced, space combat game. You are tasked with defending a refugee fleet as you travel the stars searching for a new colony to call home. In each of the game's missions you will need to fight off enemies ranging from small stunt fighters to giant capital ships. You will encounter a variety of enemies, including The Alliance forces who's attack drove you from your home planet, the reclusive Thaalian Empire, and the combat thirsty Space Pirates. Earning medals for completing each mission with certain goals (such as shot accuracy, lives lost, targeting computer usage, and finding hidden power cubes) grant you unlocked perks. Unlocking additional ships, upgrades, and more will help you protect the fleet on it's journey.

Source: Steam Store Description