Just a small note for others reading this that the Enzyme API for setting the runtime activity has been updated, so that the usage would now be:
import ADTypes
import Enzyme
using Turing
@model function m()
x ~ Normal()
y ~ Normal(x, 1)
end
model = m()
sampler = NUTS(; adtype=ADTypes.AutoEnzyme(; mode=Enzyme.set_runtime_activity(Enzyme.Reverse)))
sample(model, sampler, 1000)