Should I protect juridically my software code?

Bonjour,
Your software "automatically" enjoys some protection from applicable copyright laws. For this reason "software as such" is not regarded as patentable invention under European patent practice, for example.
Naturally, certain technical aspects of your software may be eligible for patent protection conferred by states for their territories. This proection cannot be obtained at a file hosting service like Github.
A sensible startup will try to protect their intangible assests, i. e. crown jewels, in an optimal way.
In order to find your way, discuss your situation with a patent attorney having experience in the field of computer-implemented inventions.
So, feel free to contact me...