> The main problem with Docker and php-src is that we need to touch the OS in
> order to make sure the new features and bugfixes will be compatible.
> Docker create a layer on top of that, right?
Correct. Honestly I was not considering the use case of testing
interactions with OS-specific features as one might do using a CI/CD
setup. Providing instructions that will work for every supported target
environment is not an easy thing to do.
I was thinking about the use case of local development where the
developer needs to build the sources on whatever OS he / she happens to
be using. Then, Docker makes much more sense as it provides a single
consistent environment that will work the same way for anyone.