Estar en la cresta de la ola

[ROBINDESBOIS]

English?

Estar en el mejor momento de una carrera.

[Rusty]

To be at the top of one's game.
To be at the peak of one's career.
To be at the height of one's career.
To be at the pinnacle/top/apex of one's career.

[ROBINDESBOIS]

You´re great my friend, thank you.