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Discussion for doc: Migrate to Drupal 9

Migrate to Drupal 9

Has anyone successfully completed this procedure?

I should add that the document I am using it this one

And the step I am stuck on it the Deploy step. When is says to merge " composerify into master" I get git error “fatal: refusing to merge unrelated histories”

I’m thinking there must be an error in the instructions earlier on but I am not expert enough to be able to figure it out (plus I feel there should be a bit more information about this step and those that follow).

Hey Adrian!

Sorry to hear you are having issues. Have you tried reading through this Doc yet? Happy to tag the right people to help you get back on track if still needed.

That is the doc I am having problems with. That is why I ask if anyone was able to use it successfully.

(Edited original post to give more information)

Tagging some of our Docs gurus to see if they can help you with this! @carolyn @joan.edwards @edwardangert can any of you lend your expertise here?

thanks, @McKennaR !

Hi @Adrianm6254 ! We’ve got a PR staged in the Docs repository (thanks, @dandaman !) that aims to clarify that section
If you’re already stuck there (I’m sorry that you’re stuck there), and can give the proposed changes a try, that’d be a tremendous help to us and other users!

Here’s a link to the relevant section in a built preview of the PR
I can check in here on the forum if that’s convenient for you, and if you’re more into leaving feedback and suggestions on GitHub, the Docs team will be working on PR 6471 and we’d love to work your feedback in to make the doc good.

Or, if that isn’t the right kind of solution for the issue you’ve encountered, let us know here and we can try to find the right person to help.


Thanks for getting back to me. I will go take a look shortly.

I have been struggling with this for almost a week (have been working with support but not getting very far with them).

I will definitely get back to you.



and the instructions were very easy to follow.

I’m a very happy camper now.

It reads like it is ready from prime-time (It’s a big improvement over the posted document).

Thank you


Hi again,

I started to upgrade my second site and see the updated instructions are there. I have found a new issue. When I create my composerify multidev I am finding that instead of it being D9, it is D8.

Shouldn’t it be D9 so it can be tested before committing it to master?

It seems the step to make the new code branch D9 is missing.

Hey @carolyn @joan.edwards can you help troubleshoot?

It might be pantheon.
If the db doesn’t upgrade to 10.4 does composer not install D9?
I just saw that the database did not upgrade.

@carolyn @joan.edwards

I’m currently getting nowhere with Pantheon as far as the db reporting the wrong version (apparently) and I would feel better if we can verify that composerify is trying to use D9 instead of D8… (so I know if this is normal or is another problem).



Turns out is was a contrib module that was conflicting with D9 causing the Drupal version to drop to 8.9.17.

Sorry we were delayed getting back to you! But I am super glad you were able to figure it out.

I am close now. One last question.

I have a D8 module that has a patch to make it D9 compatible. My question is how do I install the module with the patch. No matter what I do composer will not install it because composer sees it as a D8 module so it does not meet requirements.

Anyone know of some way to get around this?