default.nix

with import <nixpkgs>{};
let
  mypkgs = haskell.packages.ghc844.override {
    overrides = super: self: {
      hmatrix = haskell.lib.overrideCabal (haskell.lib.doJailbreak (self.callHackage "hmatrix" "0.15.0.0" {})) (drv: {
        patches = [ ./hide-join.patch ];
      });
    };
  };
in
  mypkgs.kmeans-par

hide-join.patch

diff -r -u -Z hmatrix-0.15.0.0-orig/lib/Data/Packed/Internal/Vector.hs hmatrix-0.15.0.0/lib/Data/Packed/Internal/Vector.hs
--- hmatrix-0.15.0.0-orig/lib/Data/Packed/Internal/Vector.hs	2019-03-25 08:28:38.802120030 -0300
+++ hmatrix-0.15.0.0/lib/Data/Packed/Internal/Vector.hs	2019-03-25 08:33:22.123932601 -0300
@@ -50,7 +50,7 @@
 import Foreign.ForeignPtr       (mallocForeignPtrBytes)
 #endif
 
-import GHC.Base
+import GHC.Base hiding (join)
 #if __GLASGOW_HASKELL__ < 612
 import GHC.IOBase hiding (liftIO)
 #endif