  A dimer model is a quiver with faces embedded into a disk. A consistent dimer
model gives rise to a strand diagram, and hence to a positroid. The
Gorenstein-projective module category over the completed boundary algebra of a
dimer model was shown by Pressland to categorify a cluster structure on the
corresponding positroid variety. Outside of the Grassmannian case, boundary
algebras of dimer models are not well understood. We give an explicit
description of the boundary algebra of a consistent dimer model as a quiver
with relations calculated only from the data of the decorated permutation or,
equivalently, Grassmann necklace of its positroid.
