Platform migration strategy

Question

Hi, 
 I would like to know the recommended strategy for migrating an on premise Appian Platform. 
 If I have 500 applications in my plateform, I can't reasonably ask each project to assure the compatibility of their application for a new version of the platform if I migrate each year. I need each project to be able to upgrade at his own pace. 
 1./ Should I have a parallel upgraded platform ? Then I can migrate application by application. But how do I transfer process data for a specific application ? 
 2./ Or maybe the platform garanties that applications are still working and that they are using deprecated functionnalities (That the project have time to correct before the next release). 
 
 What is the recommended strategy ?

Eliot Gerson · Accepted Answer

Julien, Appian is fully committed to backwards compatibility. Whether you have 1 application or 500, it should be the case that they all work seamlessly after an update to the Appian platform. If you ever encounter any issues with this, simply create a support case, and we'll be happy to work with you to quickly resolve them. 
 
Occasionally, some functionality will be deprecated. In these cases, we will not simply pull it out from under you. We will mention the deprecation in the release notes, suggest that you stop using the deprecated functionality for new development, and give you ample time to transition to replacement functionality before we even consider removing the deprecated functionality. We recognize that many customers are using Appian at large scale, and we approach deprecation with this in mind. I'll also note that cases of removal are rare, and almost always apply to functionality that we've been able to confirm is not in use (and, again, always follow a lengthly deprecation process).