  The Maurer-Cartan algebra of a Lagrangian $L$ is the algebra that encodes the
deformation of the Floer complex $CF(L,L;\Lambda)$ as an $A_\infty$-algebra. We
identify the Maurer-Cartan algebra with the $0$-th cohomology of the Koszul
dual dga of $CF(L,L;\Lambda)$. Making use of the identification, we prove that
there exists a natural isomorphism between the Maurer-Cartan algebra of $L$ and
a suitable subspace of the completion of the wrapped Floer cohomology of
another Lagrangian $G$ when $G$ is \emph{dual} to $L$ in the sense to be
defined. In view of mirror symmetry, this can be understood as specifying a
local chart associated with $L$ in the mirror rigid analytic space. We examine
the idea by explicit calculation of the isomorphism for several interesting
examples.
