Thank you @juliohm, @lmiq, @yolhan_mannes, @Satvik, @tverho for your answers.
I will definitely consider writing my solver in Julia, according to you, I will reach similar performance as c++ since optimizing will be easier, while my work will be more comfortable in Julia.
I did not know about MaterialPointSolver.jl. It’s a great bonus, I would be able to follow an example in Julia with its optimization features.