Each country may still have the equivalent of a constitution, and the majority of EU laws are directives which the country may translate to fit their local law, also there’s various negotiated exceptions to EU laws. But the general idea is that the treaties establishing EU are meant to require full cooperation
https://commission.europa.eu/law/law-making-process/types-eu-law_en
Each country may still have the equivalent of a constitution, and the majority of EU laws are directives which the country may translate to fit their local law, also there’s various negotiated exceptions to EU laws. But the general idea is that the treaties establishing EU are meant to require full cooperation