ENUBET has been designed to monitor lepton production in the decay tunnel of neutrino beams at single particle level and to provide a 1% measurement of the neutrino flux at source. In particular, the three body semileptonic decay of kaons monitored by large angle positron production offers a fully controlled $\nu_e$ source at the GeV scale for a new generation of short baseline experiments. The ENUBET Collaboration presented at ICHEP the first end-to-end simulation of the beamline and a review of the performance of this non-conventional technique. Special emphasis has been given to the new static focusing system that was validated in 2018. We also discussed the performance of the positron tagger tested at CERN in 2017-2018 and the expected sensitivity of ENUBET for $\nu_e$ and $\nu_\mu$ events.