waitforit | Wait until an address become | Date Time Utils library

but I want to reuse a variable within the manifests.

This is not how you typically work with Kustomize. Its a good thing that things are declarative and explicit when working with Kustomize.

when developers do PRs for releases, they should only touch one reference to the commit ID to prevent typos etc. (also easier to review instead of checking commit ID in N places)

yes and no.

That there is a change in four places should not be seen as a problem, in my opinion. That there is human toil to update four places is the problem.

The solution to human toil is typically automation. By using yq in an automated pipeline (e.g. Jenkins - or a shellscript) can you automate your manifest-update to take a single parameter - this can optionally be automated directly for each build after you have a git "commit id" available. The pipeline need to run four yq-commands to update the four Yaml fields. See e.g. assign operation and github action - pipeline example. No other variables are needed.

yeah... debugger helps... I have never seen Promise.all() fail to do what it is supposed to. in the debugger you would see very quickly that your json simply contains something else than you expected - a function instead of a Promise returned by this function.

Just try

You can do it like this: