There's no money in backends unless you have a great enterprise sales team.

SAS, Matlab, Oracle, Arc, there's lots of really boring backend systems with plenty of FOSS alternatives but you need sales.

If the customer is the developer, then they might ask their manager for a text editor with a nice UI. If the customer is the whole enterprise, then someone needs to wine and dine the CEO to get that $10,000 per core contract signed.