  We prove that every $0$-shifted symplectic structure on a derived Artin
$n$-stack admits a curved $A_{\infty}$ deformation quantisation. The classical
method of quantising smooth varieties via quantisations of affine space does
not apply in this setting, so we develop a new approach. We construct a map
from DQ algebroid quantisations of unshifted symplectic structures on a derived
Artin $n$-stack to power series in de Rham cohomology, depending only on a
choice of Drinfeld associator. This gives an equivalence between even power
series and certain involutive quantisations, which yield anti-involutive curved
$A_{\infty}$ deformations of the dg category of perfect complexes. In
particular, there is a canonical quantisation associated to every symplectic
structure on such a stack, which agrees for smooth varieties with the
Kontsevich--Tamarkin quantisation for even associators.
