  We construct type I string models with supersymmetry broken by
compactification that are non-tachyonic and have exponentially small effective
potential at one-loop. All open string moduli can be stabilized, while the
closed string moduli remain massless at one-loop. The backgrounds of interest
have rigid Wilson lines by the use of stacked branes, and some models should
have heterotic duals. We also present non-tachyonic backgrounds with positive
potentials of runaway type at one-loop. This class of models could be used to
test various swampland conjectures.
