Hello, Using ghc 8.2.2 (debian) , I got the following error while building the package with cabal 2.0: Building library for tensorflow-proto-0.1.0.0.. creating dist/build /media/travail/ghc/bin/ghc --make -fbuilding-cabal-package -O -static -dynamic-too -dynosuf dyn_o -dynhisuf dyn_hi -outputdir dist/build -odir dist/build -hidir dist/build -stubdir dist/build -i -idist/build -i. -idist/build/autogen -idist/build/global-autogen -Idist/build/autogen -Idist/build/global-autogen -Idist/build -I. -optP-include -optPdist/build/autogen/cabal_macros.h -this-unit-id tensorflow-proto-0.1.0.0-A707TW4oXcjUPzDlNSl3T -hide-all-packages -Wmissing-home-modules -package-db dist/package.conf.inplace -package-id proto-lens-0.2.2.0-4VJbI6HHabd74gTwpFhCiY -package-id proto-lens-protoc-0.2.2.3-KiMlOomTiwkJiIiDqOmBdc -package-id base-4.10.1.0 -XHaskell2010 Proto.Tensorflow.Core.Framework.AttrValue Proto.Tensorflow.Core.Framework.Graph Proto.Tensorflow.Core.Framework.NodeDef Proto.Tensorflow.Core.Framework.OpDef Proto.Tensorflow.Core.Framework.ResourceHandle Proto.Tensorflow.Core.Framework.Summary Proto.Tensorflow.Core.Framework.Tensor Proto.Tensorflow.Core.Framework.TensorShape Proto.Tensorflow.Core.Framework.Types Proto.Tensorflow.Core.Protobuf.Config Proto.Tensorflow.Core.Util.Event Proto.Tensorflow.Core.Framework.AllocationDescription Proto.Tensorflow.Core.Framework.CostGraph Proto.Tensorflow.Core.Framework.Function Proto.Tensorflow.Core.Framework.StepStats Proto.Tensorflow.Core.Framework.TensorDescription Proto.Tensorflow.Core.Framework.Versions Proto.Tensorflow.Core.Protobuf.Debug [ 1 of 18] Compiling Proto.Tensorflow.Core.Framework.AllocationDescription ( dist/build/autogen/Proto/Tensorflow/Core/Framework/AllocationDescription.hs, dist/build/Proto/Tensorflow/Core/Framework/AllocationDescription.o ) dist/build/autogen/Proto/Tensorflow/Core/Framework/AllocationDescription.hs:159:15: error: ⢠Couldn't match expected type âData.ProtoLens.MessageDescriptor AllocationDescriptionâ with actual type âData.Map.Map Prelude.String (Data.ProtoLens.FieldDescriptor AllocationDescription) -> Data.ProtoLens.MessageDescriptor AllocationDescriptionâ ⢠Probable cause: âData.ProtoLens.MessageDescriptorâ is applied to too few arguments In the expression: Data.ProtoLens.MessageDescriptor (Data.Map.fromList [(Data.ProtoLens.Tag 1, requestedBytes__field_descriptor), (Data.ProtoLens.Tag 2, allocatedBytes__field_descriptor), (Data.ProtoLens.Tag 3, allocatorName__field_descriptor), (Data.ProtoLens.Tag 4, allocationId__field_descriptor), ....]) (Data.Map.fromList [("requested_bytes", requestedBytes__field_descriptor), ("allocated_bytes", allocatedBytes__field_descriptor), ("allocator_name", allocatorName__field_descriptor), ("allocation_id", allocationId__field_descriptor), ....]) Does it mean that I have the wrong version of proto-lens ? * proto-lens Synopsis: A lens-based implementation of protocol buffers in Haskell. Default available version: 0.3.1.0 Installed versions: 0.2.2.0, 0.3.1.0 Homepage: https://github.com/google/proto-lens#readme License: BSD3 -- Fabien