diff --git a/src/Flux.jl b/src/Flux.jl
index 0b57f81d..95bdcd32 100644
--- a/src/Flux.jl
+++ b/src/Flux.jl
@@ -20,17 +20,19 @@ export SGD, Descent, ADAM, Momentum, Nesterov, RMSProp,
   ADAGrad, AdaMax, ADADelta, AMSGrad, NADAM,
   ADAMW, RADAM, InvDecay, ExpDecay, WeightDecay
 
+
+allow_cuda() = parse(Bool, get(ENV, "FLUX_USE_CUDA", "true"))
+const consider_cuda = allow_cuda()
+
 using CUDAapi
-if has_cuda()
+const use_cuda = consider_cuda && has_cuda()
+if use_cuda
   try
     using CuArrays
-    @eval has_cuarrays() = true
-  catch ex
-    @warn "CUDA is installed, but CuArrays.jl fails to load" exception=(ex,catch_backtrace())
-    @eval has_cuarrays() = false
+  catch
+    @error "CUDA is installed, but CuArrays.jl fails to load. Please fix the issue, or load Flux with FLUX_USE_CUDA=false."
+    rethrow()
   end
-else
-  has_cuarrays() = false
 end
 
 include("utils.jl")
@@ -47,8 +49,22 @@ include("data/Data.jl")
 
 include("deprecations.jl")
 
-if has_cuarrays()
+if use_cuda
   include("cuda/cuda.jl")
 end
 
+function __init__()
+  # check if the GPU usage conditions that are baked in the precompilation image
+  # match the current situation, and force a recompilation if not.
+  if (allow_cuda() != consider_cuda) || (consider_cuda && has_cuda() != use_cuda)
+      cachefile = if VERSION >= v"1.3-"
+          Base.compilecache_path(Base.PkgId(Flux))
+      else
+          abspath(DEPOT_PATH[1], Base.cache_file_entry(Base.PkgId(Flux)))
+      end
+      rm(cachefile)
+      error("Your set-up changed, and Flux.jl needs to be reconfigured. Please load the package again.")
+  end
+end
+
 end # module
diff --git a/src/functor.jl b/src/functor.jl
index 1d3e1bb2..b96d21c8 100644
--- a/src/functor.jl
+++ b/src/functor.jl
@@ -73,7 +73,7 @@ end
 
 cpu(m) = fmap(x -> adapt(Array, x), m)
 
-const gpu_adaptor = if has_cuarrays()
+const gpu_adaptor = if use_cuda
   CuArrays.cu
 else
   identity
diff --git a/src/onehot.jl b/src/onehot.jl
index fe93c5c5..84747450 100644
--- a/src/onehot.jl
+++ b/src/onehot.jl
@@ -37,7 +37,7 @@ import Adapt: adapt, adapt_structure
 
 adapt_structure(T, xs::OneHotMatrix) = OneHotMatrix(xs.height, adapt(T, xs.data))
 
-if has_cuarrays()
+if use_cuda
   import .CuArrays: CuArray, cudaconvert
   import Base.Broadcast: BroadcastStyle, ArrayStyle
   BroadcastStyle(::Type{<:OneHotMatrix{<:CuArray}}) = ArrayStyle{CuArray}()