At ACT Financial Systems, I worked on Quasar, an investment management system written in Mumps, running on Digital VMS and Sequent (Unix) systems.
Quasar featured a core system with general functions and libraries of reusable procedures, along with numerous modules offering various client features, which were sold and supported individually.
In my role, I provided support for many of these modules, assisting major investment banks such as Lloyds, Barclays, Midland (now part of HSBC), and NatWest.