Here is the full list of all 16 Scrapper achievements.
Earn a cumulative total of 500,000 points
Earn a total of 2000 scrap
Have 1000 unspent scrap
Roll for one minute without stopping or dying
Completed a mission on hard difficulty
Unlock a total of twenty one different ship parts
Upgrade your Scrapper rank to level 19
Complete a checkpoint mission
Complete a collect mission
Upgrade your Scrapper rank to level 10
Complete a survive mission
Unlock a total of ten different ship parts
Complete a goal mission
Completed a mission on any difficulty
Upgrade your Scrapper rank to level 2
Get 50,000 points in a single run