  Polarized general-relativistic radiative transfer in the vicinity of black
holes and other compact objects has become a crucial tool for probing the
properties of relativistic astrophysics plasmas. Instruments like GRAVITY, the
Event Horizon telescope, ALMA, or IXPE make it very timely to develop such
numerical frameworks. In this article, we present the polarized extension of
the public ray-tracing code Gyoto, and offer a python notebook allowing to
easily perform a first realistic computation. The code is very modular and
allows to conveniently add extensions for the specific needs of the user. It is
agnostic about the spacetime and can be used for arbitrary compact objects. We
demonstrate the validity of the code by providing tests, and show in particular
a perfect agreement with the ipole code. Our article also aims at pedagogically
introducing all the relevant formalism in a self-contained manner.
