  Resonant inelastic x-ray scattering (RIXS) is an extremely valuable tool for
the study of elementary, including magnetic, excitations in matter. Latest
developments of this technique mostly aimed at improving the energy resolution
and performing polarization analysis of the scattered radiation, with a great
impact on the interpretation and applicability of RIXS. Instead, this article
focuses on the sample environment and presents a setup for high-pressure
low-temperature RIXS measurements of low-energy excitations. The feasibility of
these experiments is proved by probing the magnetic excitations of the bilayer
iridate Sr$_3$Ir$_2$O$_7$ at pressures up to 12 GPa.
