diff --git a/pkgs/build-support/cabal/ghcjs.nix b/pkgs/build-support/cabal/ghcjs.nix
index d74c30180e2..e6bc50f4516 100644
--- a/pkgs/build-support/cabal/ghcjs.nix
+++ b/pkgs/build-support/cabal/ghcjs.nix
@@ -188,7 +188,7 @@ in
                 done
               done
 
-              configureFlags+=" --package-db=${ghc.ghc}/share/ghcjs/x86_64-linux-0.1.0-7.8.2/ghcjs/package.conf.d"
+              configureFlags+=" --package-db=${ghc.ghc}${ghc.ghc.libdir}/ghcjs/package.conf.d"
 
               ${optionalString (self.enableSharedExecutables && self.stdenv.isLinux) ''
                 configureFlags+=" --ghc-option=-optl=-Wl,-rpath=$out/lib/${ghc.ghc.name}/${self.pname}-${self.version}";
diff --git a/pkgs/development/tools/haskell/ghcjs/default.nix b/pkgs/development/tools/haskell/ghcjs/default.nix
index 55e3d5875e7..7602bf70811 100644
--- a/pkgs/development/tools/haskell/ghcjs/default.nix
+++ b/pkgs/development/tools/haskell/ghcjs/default.nix
@@ -77,6 +77,7 @@ cabal.mkDerivation (self: rec {
     sed -i -e "s|str = \\[\\]|str = [\"--prefix=$out\", \"--libdir=$prefix/lib/$compiler\", \"--libsubdir=$pkgid\"]|" \
       src-bin/Boot.hs
   '';
+  libdir = "/share/ghcjs/${pkgs.stdenv.system}-${version}-${ghc.ghc.version}";
   postInstall = ''
     export HOME=$(pwd)
     export GIT_SSL_CAINFO="${cacert}/etc/ca-bundle.crt"
@@ -86,7 +87,7 @@ cabal.mkDerivation (self: rec {
     git submodule update --init --recursive
     ( cd boot ; chmod u+w . ; ln -s .. ghcjs-boot )
     chmod -R u+w .              # because fetchgit made it read-only
-    local GHCJS_LIBDIR=$out/share/ghcjs/${pkgs.stdenv.system}-${version}-${ghc.ghc.version}
+    local GHCJS_LIBDIR=$out${libdir}
     ensureDir $GHCJS_LIBDIR
     cp -R ${shims} $GHCJS_LIBDIR/shims
     ${cabalInstallGhcjs}/bin/cabal-js update