  Photonic information processing demands programmable multiport
interferometers capable of implementing arbitrary transfer matrices, for which
planar meshes of error-sensitive Mach-Zehnder interferometers are usually
exploited. We propose an alternative design that uses a single static
beam-splitter and a variable phase shift as the building block. The design
possesses superior resilience to manufacturing errors and losses without extra
elements added into the scheme. Namely, the power transmissivities of the
static BSs can take arbitrary values in the range from $\approx{}1/2$ to
$\approx{}4/5$. We show that the fraction of transfer matrices
non-implementable by the interferometers of our design diminishes rapidly with
their size.
