Relativistic plasma is ubiquitous in astrophysics. Such a plasma can be found anywhere from pulsar magnetospheres to supernova remnants and turbulent accretion disks. A common tool in the past has been to simulate such a plasma with magnetohydrodynamics (MHD). Experience has, however, shown that in some cases the environment can be such an extreme that assumption of thermally relaxed plasma is no longer valid and, hence, MHD is not applicable. More general framework to describe such a plasma is the relativistic 6-dimensional Vlasov equation. We are currently developing a new state-of-the-art collection of numerical tools to simulate such a plasma: a plasma-toolbox. As an first application, this toolbox can be applied to study neutron star atmospheres where 1-dimensional non-linear plasma instabilities might occur. Here we apply for HPC resources in order to test the code and run the first 1-dimensional simulations.