The vessel known as the Backstab, which was also referred to as the Captain's Ladder, was a CR90 corvette that was used by a collection of pirates and also some mercenaries.
Backstab was originally a component of the fleet belonging to the Eyttyrmin Batiiv pirate organization, which included more than 70 starfighters, 50 armed yachts, and 27 other corvettes.
This fleet was almost entirely destroyed during the Battle of Khuiumin by two Imperial Navy Victory-class Star Destroyers, namely the Crusader and the Bombard. The resulting devastation left the Backstab as the only warship to survive from the group, largely because of the tactical skill and the discipline exhibited by her captain, Jacob Nive. After this particular battle, the remaining pirates of the Bastiv reorganized themselves into the Khuiumin Survivors, with Nive leading them, and they dedicated their efforts to fighting against Imperial forces and also to looting Imperial convoys whenever they could.
At some point after the Survivors went back to piracy activities following the Battle of Endor, the Backstab, together with the rest of the Survivors, became a part of the Invid pirate fleet, sometimes using the alias Captain's Ladder. Following the fall of the Invids in 11 ABY, the Survivors, who by this point had joined the New Republic and moved to Susevfi, continued to make use of the Backstab as the central element of the defense force for the moon that was formerly under Imperial control, working alongside their Tri-fighters and the Jensaari.