I'm running my PHP application on Google Cloud App Engine Standard. After I deployed a new version of my app with a new composer package, I see that this new package was not installed during the deployment.
I deploy my app with gcloud app deploy. In the Cloud Console Debug tool, I can't find the package in the vendor folder. The package is successfully installed locally.
Is there a trick to update composer packages?
I had this problem too. Turns out this only works for '2nd generation run times'. In other words, your application will need to be PHP7.3. php5 applications will not process composer files.