We present a concept for a coded‐mask All Sky Monitor based on Silicon Drift Detectors. The current design has a high level of readiness, minimizes the total weight ( 2 steradians and an on‐axis sensitivity of ∼3 mCrab (5σ, 50 ks). The intrinsic modularity of the detector allows to envisage experiments with different configurations, in terms of field of view, angular resolution or effective area. We show the expected scientific performances of such an experiment, with emphasis on the observations of X‐ray Galactic transients and gamma‐ray bursts.