My understanding is if we only upgrade Pega platform, the application may or may not work. The bigger the version gap is, the more the application breaks. Every time platform is upgraded, we will need to upgrade application (technically I mean override broken components) as well to work on a new version. Am I correct? Is there new plan for product (or Pega) to guarantee that old application would work on any future version?
Each version of Pega will have some new rules which were not present in the previous versions. Also, there will be some functionalities/controls etc. which will be deprecated in those new versions. Thus, I don't think from Pega side we can guarantee that an old application would work on any future releases. There may be some other challenges which currently I am not aware of.
Pega does provide support for backward compatibility. There are certain tools like HTML 5 Readiness, Pega Accelerator Product etc which assist in upgrading the deprecated or rules which wouldn't work well with the latest release.
No, Pega is "Build for change" and the application will work in the latest versions and if any functionality fails, it needs to be reported as a support request with GCS and each issue could be taken as an individual issue.
As the world is agile, any progressive product needs to accommodate the change otherwise won't be able to compete. So, nothing can be robust for another couple of years down the line in terms of leveraging latest technology available at that time. Pega incorporates latest of them to make the product better for Pega user in every aspect and provide all the competent technology to be used for delivering best business solutions.
I could say, "Change is the only constant" and adaptability is the beauty. Pega products are adaptable and if not, they're assisted by teams at Pega to the greater extent to make application runs smoothly for a business after the upgrade.
For the current release (up to 7.4) I do not think backward compatibility would be supported but I heard Pega Cloud will start supporting this in the future. I am not sure if this is Pega Cloud feature or product feature or even official feature available somewhere on company website. If this information is not true, please forget it, I just wanted to double check if that is right.