The beauty of the rare: $B_{(s)}\to {\mu }^{+}{\mu }^{-}$ at the LHCb

The latest and improved measurements in $B_{(s)}^0\to {\mu }^{+}{\mu }^{-}$ processes have been performed by LHCb using full Run 1 and Run 2 data. The measurement of the branching fraction of $B_s^0\to {\mu }^{+}{\mu }^{-}$ is presented as the most precise single experiment measurement of such a rare process. While no significant excess is found for $B^0\to {\mu }^{+}{\mu }^{-}$, an stringent upper limit is set for its braching fraction. Both results are in agreement with SM predictions and with previous results.