One of my earliest programming jobs as a college student was programming BASIC for Wang 2200MVP systems. A couple business school graduates had formed a partnership to develop semi-custom computer applications to support agribusiness corporations in Latin America. They got some hardware through one of Wang's developer programs (which my father worked on at the time, around 1981-1982). They also needed programming help, and my father referred them to me.

They had developed quite a capable application, which is amazing given the limitations of the system. The 2200 was memory-limited (both code and data) and so in order to deal with this limit, we had to use code overlays. And the BASIC (mostly) didn't support symbols for subroutines, so we had to use line number conventions. For example, lines 8000-8999 might have been designated as the overlay area. To load some overlay routines, those lines would first need to be cleared, and new code would be loaded that by convention would start at line 8000.

And subroutines (mostly) didn't have parameters or return values, so we had to keep conventions for all the different subroutines to take parameters in certain named variables and to return values in other named variables. There were no local variables, so all the code needed to conform to some conventions over use of temporary variables so that different parts of the code didn't stomp on each others' data.

I don't remember much else about the system, but they did manage to get the Simplex Algorithm working well enough to solve optimization problems, such as where to apply resources in order to maximize revenue.

I also got a trip to Ecuador out of it in order to do a customer installation. Pretty cool for a college student to get international business travel.