I feel like I'm actually leading the projects I'm on and adding value.

However, since I depend on VISA sponsorship I have accepted a salary of 32K€ (before tax).

I have been working for a year and have ZERO savings, I can't afford vacation and I feel like I'm being exploited.

Should I ask for a raise? If yes, how?

PS: I work in the south of France[0] where most IT workers are depending on VISAs so companies are very aware of the situation.

[0]: https://en.wikipedia.org/wiki/Sophia_Antipolis