The study of the generation, physics and mitigation of runaway electrons (RE) is very important because the RE beam can severely damage plasma-facing components of tokamaks. The GOLEM tokamak is a useful testbed for RE diagnostics because it is easy to generate runaway electrons due to the low plasma density and high toroidal electric field, especially considering the recently improved technological parameters of GOLEM, which lead to much longer discharges and runaway electron currents than ever before. An overview of the current state of runaway electron measurements will be presented, including a description of various scintillation detectors, the Timepix3 semiconductor pixel detector and a new design of in-vessel probe for direct RE measurements. A progress in data analysis and modeling will be shown.