  We present a code implementing the linearized self-consistent quasiparticle
GW method (scQPGW) in the LAPW basis. Our approach is based on the
linearization of the self-energy around zero frequency which differs it from
the existing implementations of the scQPGW method. The linearization allows us
to use Matsubara frequencies instead of real ones. As a result it gives us an
advantage in terms of efficiency, allowing us easily switch to the imaginary
time representation the same way as in the space time method. The all electron
LAPW basis set eliminates the need for pseudopotentials. We discuss the
advantages of our approach, such as its N^3 scaling with the system size, as
well as its shortcomings.
  We apply our approach to study electronic properties of selected
semiconductors, insulators, and simple metals and show that our code produces
results very close to the previously published scQPGW data. Our implementation
is a good platform for further many body diagrammatic resummations such as
GW+DMFT.
