VAE in Flux model zoo

I’ve been unable to get the MNIST VAE example in Flux’s model zoo to train.

During epoch 1 of training, I get this error:

[ Info: Epoch 1
ERROR: Mutating arrays is not supported
 [1] (::Zygote.var"#1003#1004")(::Nothing) at /Users/rs990e/.julia/packages/Zygote/oMScO/src/lib/array.jl:53
 [2] (::Zygote.var"#2668#back#1005"{Zygote.var"#1003#1004"})(::Nothing) at /Users/rs990e/.julia/packages/ZygoteRules/6nssF/src/adjoint.jl:49
 [3] push! at /Users/rs990e/.julia/packages/Zygote/oMScO/src/compiler/interface.jl:65 [inlined]
 [4] (::typeof(∂(push!)))(::Nothing) at /Users/rs990e/.julia/packages/Zygote/oMScO/src/compiler/interface2.jl:0
 [5] params! at /Users/rs990e/.julia/packages/Flux/2i5P1/src/functor.jl:42 [inlined]

Could it be something I’m doing wrong?

Using Julia 1.3.1 and Flux 0.10.1