  The Gamma Beam System (GBS) is a high brightness LINAC to be installed in
Magurele (Bucharest) at the new ELI-NP (Extreme Light Infrastructure - Nuclear
Physics) laboratory. The accelerated electrons, with energies ranging from 280
to 720 MeV, will collide with a high power laser to produce tunable high energy
photons (0.2-20MeV ) with high intensity (10e13 photons/s), high brilliance and
spectral purity (0.1% BW), through the Compton backscattering process. This
light source will be open to users for nuclear photonics and nuclear physics
advanced experiments. Tested high level applications will play an important
role in commissioning and operation. In this paper we report the progress and
status of the development of dedicated high level applications. We also present
the results of the test on the FERMI LINAC of the electron trajectory control
method based on Dispersion Free Steering.
