diff --git a/openhab.nix b/openhab.nix
index 090d44f..cad9280 100644
--- a/openhab.nix
+++ b/openhab.nix
@@ -1,71 +1,75 @@
 {
- bash,
- coreutils,
- fetchurl,
- gawk,
- jdk-openhab,
- lib,
- makeWrapper,
- procps,
- zip,
- unzip,
- stdenv,
-}:
-
-let
-    version = builtins.readFile ./version;
-    sha256 = builtins.readFile ./openhab.sha256;
-in stdenv.mkDerivation rec {
+  bash,
+  coreutils,
+  fetchurl,
+  gawk,
+  jdk-openhab,
+  lib,
+  makeWrapper,
+  procps,
+  zip,
+  unzip,
+  stdenv,
+  gnused,
+}: let
+  version = builtins.readFile ./version;
+  sha256 = builtins.readFile ./openhab.sha256;
+in
+  stdenv.mkDerivation rec {
     inherit version;
     pname = "openhab";
     src = fetchurl {
-        url = "https://github.com/openhab/openhab-distro/releases/download/${version}/openhab-${version}.tar.gz";
-        inherit sha256;
+      url = "https://github.com/openhab/openhab-distro/releases/download/${version}/openhab-${version}.tar.gz";
+      inherit sha256;
     };
-    nativeBuildInputs = [ makeWrapper ];
-    buildInputs = [ bash ];
-    outputs = [ "out" ];
-    extraPath = lib.makeBinPath [ jdk-openhab gawk coreutils procps zip unzip ];
+    nativeBuildInputs = [makeWrapper gnused];
+    buildInputs = [bash];
+    outputs = ["out"];
+    extraPath = lib.makeBinPath [jdk-openhab gawk coreutils procps zip unzip];
     wrappedExecutables = [
-        "start.sh"
-        "start_debug.sh"
-        "runtime/bin/karaf"
-        "runtime/bin/backup"
-        "runtime/bin/client"
-        "runtime/bin/instance"
-        "runtime/bin/karaf"
-        "runtime/bin/restore"
-        "runtime/bin/shell"
-        "runtime/bin/start"
-        "runtime/bin/status"
-        "runtime/bin/stop"
-        "runtime/bin/update"
+      "start.sh"
+      "start_debug.sh"
+      "runtime/bin/karaf"
+      "runtime/bin/backup"
+      "runtime/bin/client"
+      "runtime/bin/instance"
+      "runtime/bin/karaf"
+      "runtime/bin/restore"
+      "runtime/bin/shell"
+      "runtime/bin/start"
+      "runtime/bin/status"
+      "runtime/bin/stop"
+      "runtime/bin/update"
     ];
 
     unpackPhase = ''
-        runHook preUnpack
-        mkdir -p $out
-        tar -C $out -xf $src
-        runHook postUnpack
+      runHook preUnpack
+      mkdir -p $out
+      tar -C $out -xf $src
+      runHook postUnpack
     '';
 
     installPhase = ''
-        runHook preInstall
-        rm -rfv \
-            "$out/"*.bat \
-            "$out/runtime/bin/"*.bat \
-            "$out/runtime/bin/"*.ps1 \
-            "$out/runtime/bin/"*.psm1
+      runHook preInstall
+      rm -rfv \
+          "$out/"*.bat \
+          "$out/runtime/bin/"*.bat \
+          "$out/runtime/bin/"*.ps1 \
+          "$out/runtime/bin/"*.psm1
 
-        for exe in $wrappedExecutables; do
-        echo "Rewriting $exe…"
-        cat - $out/$exe > "$out/$exe".new << EOF
-        #!${bash}/bin/sh
-        export PATH="\''$PATH:$extraPath"
-        EOF
-        mv "$out/$exe".new "$out/$exe"
-        done
+      for exe in $wrappedExecutables; do
+      echo "Rewriting $exe…"
+      cat - $out/$exe > "$out/$exe".new << EOF
+      #!${bash}/bin/sh
+      export PATH="\''$PATH:$extraPath"
+      EOF
+      mv "$out/$exe".new "$out/$exe"
+      done
 
-        runHook postInstall
+      # Fix OPENHAB_HOME overwritting
+      sed '6d' "$out/runtime/bin/oh_dir_layout" | sed '6i if [ -z ''${OPENHAB_HOME} ]; then\n\texport OPENHAB_HOME=`cd "$DIRNAME/../.."; pwd`\nfi' > "$out/runtime/bin/oh_dir_layout.new"
+      mv "$out/runtime/bin/oh_dir_layout.new" "$out/runtime/bin/oh_dir_layout"
+
+      runHook postInstall
     '';
-}
+  }