Low Reynolds number fluid flows are governed by the Stokes equations. In two
dimensions, Stokes flows can be described by two analytic functions, known as
Goursat functions. Brubeck and Trefethen (2022) recently introduced a lightning
Stokes solver that uses rational functions to approximate the Goursat functions
in polygonal domains. In this paper, we present a solver for computing 2D
Stokes flows in domains with smooth boundaries and multiply-connected domains
using lightning and AAA rational approximation (Nakatsukasa et al., 2018). This
leads to a new rational approximation algorithm "LARS" that is suitable for
computing many bounded 2D Stokes flow problems. After validating our solver
against known analytical solutions, we solve a variety of 2D Stokes flow
problems with physical and engineering applications. The computations take less
than a second and give solutions with at least 6-digit accuracy