So just is an exclamation of joy or approval. It is applicable wherever something particularly good has happened, or where someone exhibits or embodies great justice.
Can sometimes be used as substitute for such phrases as "based," "keyed," or "excellent," although use of "so just" is more specifically to be applied to instances of justice.
When you’re a bad ass contractor who lays pipe like you lay tile. Jack of all trades and almost a master of all. Because you workhard you party harder. Ripping motocross on the weekends. Your travel trailer for motocross looks like a portable man cave with a boom boom room in it complete with a strip pole. Due to this all the Moto Lizards (aka hot single moms with cut off jean shorts, big moon balloons, usually wearing ripped t-shirts or folded flannel shirts to show off their chest trophies who bring their kids to the races every weekend) want to party in your travel trailer. They are looking for you to show them how you down shift while riding from the back to lift up their front end all the while kicking your legs straight out as if you are performing a Superman jump off a dirt ramp. But your real claim to fame is how all the Au Pairs for all the remodels you do for rich clients want you to show them how you lay your huge pipe.
Who’s that guy? That’s Jason. Who the fuck is Jason? You don’t know? They call him the Canadian Just Jason