  To facilitate the implementation of large scale photonic quantum walks, we
have developed a polymer waveguide platform capable of robust, polarization
insensitive single mode guiding over a broad range of visible and near-
infrared wavelengths. These devices have considerable elasticity, which we
exploit to enable tuning of optical behaviour by precise mechanical
deformations. In this work, we investigate pairs of beamsplitters arranged as
interferometers. These systems demonstrate stable operation over a wide range
of phases and reflectivities. We discuss device performance, and present an
outlook on flexible polymer chips supporting large, reconfigurable optical
circuits.
