ouch, you're going in very specific here. It's going to hurt.
About the EU law : you are not subject to it, it's countries who are subject to it. It work by fining the infringing country. EU laws generally mandate countries to have national laws in this or that way. If a citizen gets a condamnation by an infringing national law, and after having tried every possible national appeals, he can go to the EU court and get his country condemned. I'll stop here on that subject.
Then you have the limits on the number of hours worked, like no more than 13h in a row, sleep time etc. It's not really about salary, it's about security and well-being. As far I as know it's not a issue in computer science.
About the EU law : you are not subject to it, it's countries who are subject to it. It work by fining the infringing country. EU laws generally mandate countries to have national laws in this or that way. If a citizen gets a condamnation by an infringing national law, and after having tried every possible national appeals, he can go to the EU court and get his country condemned. I'll stop here on that subject.
So, on a French level, we have work laws (Code du travail), regulations and "collective agreement" (I hope my google translation is correct). In computer science the collective agreement is called "syntec" it has force of law (it's not the case for all agreements). Collective agreements can offer better benefits than the law, but not worse. In the case of computer science, the employees are classified in 2 layers, basic employees (secretaries etc.) and "Managers and Engineers" (Cadres et Ingénieurs) in startups, almost everybody is an engineer. Then engineers are classified with a number, depending on experience, autonomy, degree of skills the job needs, and people managed. This number (coefficient) correspond to the minimum salary you have to pay them, and the other way around, if in everyday work, their job goes into a higher level, their minimum salary have to be increased (if you were already paying them high than the minimum, you don't care). For computer science we are generally way over the minimum, but it's good to have someone check the employment contract before signing it. Employers tend to give lower number at employment, I tend to raise it to their true level, because I value my team on paper too. People whose number is high enough meaning their seniority is high enough are to be paid by the day and not the hour. Those people are paid to work 218 days a year (waiting for some backlash here:) ).
Then you have the limits on the number of hours worked, like no more than 13h in a row, sleep time etc. It's not really about salary, it's about security and well-being. As far I as know it's not a issue in computer science.