Composer install error:

[mp3tk0v]

I'm trying to run the demo on Docker (Windows) with php7.2 but I can't get past this issue. Maybe I'm missing something simple, I'd appreciate your input.

[mp3tk0v]

Figured it out. Your project does not work on 4.+
Swap the head to ProPheT777's merge

[jjsaunier]

Currently support for symfony4 is in RC, see latest release. And the stable release is soon !