Does anyone has experience with upgraden Mx applications from 7 to 9?

Where did you struggle?   Did you upgrade from 7 to 8 to 9 in one go? Or did you fix at 8 the errors?
2 answers



You need to update to 8 first, solve all errors and deprecations. Be sure to update all marketplace modules.

If you have custom Java code of yourself or supplies, make sure deprecations are gone before moving to 9 as these mostly will become errors. The Mendix 8 Javadocs have pretty good explanations of the deprecations.

Check my blog post here:

It helps with details of migrating from 7 to 8. 

After you have a running mendix 8 version, you can move to 9.

Be sure to commit each step to the repository. Have a working Mendix 7 copy or branch available to check for layout or userlib differences.

As of the latest Mendix 8 versions, the update widget tool in the project / app tools menu works really well.

Upgrading from 8 to 9 is actually more straight forward. Do this in two steps: First get a working Mendix 9 version. After that, migrate your theme to Atlas 3. It is perfectly fine to go live with a Mendix 9 app with Atlas 2 and migrate to Atlas 3 later.


Edit: Check these doc pages:



My experience with migrating from 7 to 8 did not went fine. I was using Atlas UI and when migrated, there issues reported in modeler which I was able to address easily. But when I ran the application, I had lot of styling issues and I m still stuck with that.