On the forefront of IT development we have development organizations that have multible releases each day. They practice true continuous delivey and take advantage of high degree of build and test automation and run their infrastructure as code (IaC).
But not all organizations are born with continuous delivery. Many older organizations still have coexistence of legacy systems that run monthly release and deploys and newer systems on the decentral platform where continous delivery is possible.
Topdanmark is a good example. We have coexistence of old mainframe-based systems and newer backend systems in Java. At the same time our web platform is build with the newest tech and runs on aws cloud.
How do balance this cooexistance and move towards continuous development in this environment. What challenges will the organization face along the way? How do you deal with organizational inertia and resistance? What are the shorcuts and pitfalls?