diff --git a/README.md b/README.md
new file mode 100644
index 0000000..a97ead9
--- /dev/null
+++ b/README.md
@@ -0,0 +1,27 @@
+# Introduction
+
+This is an update of the Hopper
+[Linux SDK](https://www.hopperapp.com/blog/?p=150) to match the
+versions of libraries shipped by more recent Hopper builds.  
+
+# Usage
+
+```
+git clone https://github.com/ckuethe/HopperSDK-Linux
+cd HopperSDK-Linux
+./install.sh
+
+. ${HOME}/hopper-gnustep.sh
+# go about your plugin development business.
+```
+
+When the build finishes, the SDK will be installed in
+`${HOME}/GNUstep/Library/ApplicationSupport/Hopper` as
+`HopperSDK-${SDKVER}` and `gnustep-$(arch)`. Additionally a symbolic
+link to `GNUstep.sh` - required to set up some environment variables
+to compile plugins - will be installed at `${HOME}/hopper-gnustep.sh`.
+On a multiuser machine, each user will need to run this SDK installer.
+
+# Notes
+* On recent Ubuntu (17.04) `libxml2-dev` `libgnutls28-dev` `libxslt1-dev`
+`libgcrypt20-dev` are to compile GNUstep base
diff --git a/install.sh b/install.sh
index 27cf4a7..9975ddb 100755
--- a/install.sh
+++ b/install.sh
@@ -3,47 +3,55 @@
 set -e
 
 ## Variables
-SUFFIX=$(uname)-$(arch)
-
 SDKVER=4.1.5
-GNUSTEP_REV=37819
-GNUSTEP_BASE_GIT=3c4ff69d696e2b5d4afacf70352b5d483b18997b # close to svn-37819
-GNUSTEP_MAKE_GIT=0b7a76a45e9f6d7dc4d982c226fff111465d1272 # close to svn-37819
-LIBDISPATCH_REV=700a514955d6c86b29439c80f3bc0b69405b43f0
+GNUSTEP_MAKE_GIT=a964f87bdecab5156ed24f224548680aa2555676 # svn-39575, probably close to what hopper was built with
+GNUSTEP_BASE_GIT=03952f1e961931828a3eba62784c02205e8c0a65 # svn-39569, hopper ships libgnustep-base 1.24.9
+LIBDISPATCH_REV=e63c3c130c5115b653beca04b7f245e20ba84a08 # hopper ships libdispatch 0.1.3.1
 
 JOBS=$(nproc)
-DEST=$(pwd)/gnustep-$SUFFIX
+DEST="${HOME}/GNUstep/Library/ApplicationSupport/Hopper"
+SDKDIR="${DEST}/HopperSDK-${SDKVER}"
+GS_DIR="${DEST}/gnustep-$(arch)"
 LAYOUT=fhs
 
 CC=clang
 CXX=clang++
 
 ## Cleanup
+mkdir -p "${DEST}"
 echo "Cleaning"
-rm -rf "$DEST"
-rm -rf sources HopperSDK
-mkdir sources HopperSDK
+rm -rf sources # comment this out to not remove downloaded sources (saves dowloads) while developing this script
+rm -rf "${DEST}/HopperSDK" "${SDKDIR}" "${GS_DIR}"
+mkdir -p "${SDKDIR}" "${GS_DIR}" sources
 
 ## Download latest Hopper SDK
 echo "Downloading sources"
 echo "  Hopper SDK"
-SDKZIP="sources/HopperSDK-${SDKVER}.zip"
-curl -A SDK -L --progress-bar -o $SDKZIP "https://d2ap6ypl1xbe4k.cloudfront.net/HopperSDK-${SDKVER}.zip"
-unzip -d HopperSDK $SDKZIP >/dev/null 2>&1
+SDK_ZIP="HopperSDK-${SDKVER}.zip"
+test -f sources/$SDK_ZIP || curl -A SDK -L --progress-bar -o sources/$SDK_ZIP "https://d2ap6ypl1xbe4k.cloudfront.net/${SDK_ZIP}"
+unzip -qq -d "${SDKDIR}" sources/$SDK_ZIP >/dev/null 2>&1
+ln -s "${SDKDIR}" "${DEST}/HopperSDK"
 
 ## Download sources
 cd sources
 echo "  libobjc2..."
-git clone -q https://github.com/gnustep/libobjc2 gnustep-libobjc2
+D=gnustep-libobjc2
+test -d $D || git clone -q https://github.com/gnustep/libobjc2 $D
+
 echo "  gnustep-make..."
-git clone -q https://github.com/gnustep/make gnustep-make
-git -C gnustep-make checkout -q $GNUSTEP_MAKE_GIT
+D=gnustep-make
+test -d $D || git clone -q https://github.com/gnustep/make $D
+git -C $D checkout -qf $GNUSTEP_MAKE_GIT
+
 echo "  gnustep-base..."
-git clone -q https://github.com/gnustep/base gnustep-base
-git -C gnustep-base checkout -q $GNUSTEP_BASE_GIT
+D=gnustep-base
+test -d $D || git clone -q https://github.com/gnustep/base $D
+git -C $D checkout -qf $GNUSTEP_BASE_GIT
+
 echo "  libdispatch..."
-git clone -q https://github.com/nickhutchinson/libdispatch.git
-git -C libdispatch checkout -q $LIBDISPATCH_REV
+D=libdispatch
+test -d $D || git clone -q https://github.com/nickhutchinson/libdispatch $D
+git -C $D checkout -qf $LIBDISPATCH_REV
 
 ## Compilation
 echo "Compilation"
@@ -51,38 +59,36 @@ SRC=$(pwd)
 ## Compile gnustep-make
 echo "  gnustep-make..."
 cd gnustep-make
-./configure CC=$CC CXX=$CXX --with-layout=$LAYOUT --prefix="$DEST"
+./configure CC=$CC CXX=$CXX --with-layout=$LAYOUT --prefix="${GS_DIR}"
 make
 make install
-cd "$DEST/bin"
-ln -s "../share/GNUstep/Makefiles/GNUstep.sh"
 
 cd $SRC
-. "$DEST/share/GNUstep/Makefiles/GNUstep.sh"
+. "${GS_DIR}/share/GNUstep/Makefiles/GNUstep.sh"
 
 ## Compile the Objective-C 2 runtime
 echo "  libobjc2..."
 cd gnustep-libobjc2
 rm -rf build ; mkdir build ; cd build
-cmake .. -DCMAKE_INSTALL_PREFIX="$DEST" -DCMAKE_C_COMPILER=$CC -DCMAKE_CXX_COMPILER=$CXX
+cmake .. -DCMAKE_INSTALL_PREFIX="${GS_DIR}" -DCMAKE_C_COMPILER=$CC -DCMAKE_CXX_COMPILER=$CXX
 make -j$JOBS
 make install
 cd $SRC
 
 cd gnustep-make
-./configure CC=$CC CXX=$CXX --enable-objc-nonfragile-abi --with-layout=$LAYOUT --prefix="$DEST"
+./configure CC=$CC CXX=$CXX --enable-objc-nonfragile-abi --with-layout=$LAYOUT --prefix="${GS_DIR}"
 make
 make install
 cd $SRC
 
-. "$DEST/share/GNUstep/Makefiles/GNUstep.sh"
+. "${GS_DIR}/share/GNUstep/Makefiles/GNUstep.sh"
 
 ## Compile GNUstep base
 # On recent Ubuntu (17.04...) you may need to do 'sudo apt install libxml2-dev libgnutls28-dev libxslt1-dev libgcrypt20-dev'
 echo "  gnustep-base..."
 cd gnustep-base
 patch -p0 <../../patches/gnustep-base.patch
-./configure CC=$CC CXX=$CXX --prefix="$DEST"
+./configure CC=$CC CXX=$CXX --prefix="${GS_DIR}"
 make -j$JOBS 2>/dev/null
 make install
 cd $SRC
@@ -94,7 +100,7 @@ patch -p1 <../../patches/libdispatch.patch
 sed -i"" "s/add_subdirectory(testing)/#add_subdirectory(testing)/" CMakeLists.txt
 mkdir build
 cd build
-cmake .. -DCMAKE_C_COMPILER=$CC -DCMAKE_CXX_COMPILER=$CXX -DCMAKE_INSTALL_PREFIX="$DEST" -DCMAKE_BUILD_TYPE=Release
+cmake .. -DCMAKE_C_COMPILER=$CC -DCMAKE_CXX_COMPILER=$CXX -DCMAKE_INSTALL_PREFIX="${GS_DIR}" -DCMAKE_BUILD_TYPE=Release
 make
 make install
 cd $SRC
@@ -147,4 +153,5 @@ _EOF
 clang test.m -o test $(gnustep-config --objc-flags) $(gnustep-config --base-libs) -fobjc-arc -fobjc-nonfragile-abi -O0 -g -ldispatch
 ./test
 echo "GNUstep for Hopper SDK ready."
-echo "source '$DEST/bin/GNUstep.sh' to use it"
+echo "source '${HOME}/hopper-gnustep.sh' to use it"
+ln -fs "${GS_DIR}/share/GNUstep/Makefiles/GNUstep.sh" "${HOME}/hopper-gnustep.sh"
diff --git a/patches/gnustep-base.patch b/patches/gnustep-base.patch
index fe6be87..12eb012 100644
--- a/patches/gnustep-base.patch
+++ b/patches/gnustep-base.patch
@@ -17,19 +17,3 @@ Index: Source/NSArray.m
        return (NSOrderedSame == CALL_BLOCK(comparator,
          key, [self objectAtIndex: index]) ? index : NSNotFound);
      }
-@@ -2025,7 +2033,14 @@
- 
- - (void) setObject: (id)anObject atIndexedSubscript: (size_t)anIndex
- {
--  [self replaceObjectAtIndex: (NSUInteger)anIndex withObject: anObject];
-+  if (anIndex == [self count]) {
-+    // From Apple documentation of -[NSMutableArray setObject:atIndexedSubscript:]
-+    // "If the index is equal to count the element is added to the end of the array, growing the array."
-+    [self addObject:anObject];
-+  }
-+  else {
-+    [self replaceObjectAtIndex: (NSUInteger)anIndex withObject: anObject];
-+  }
- }
- 
- /** Replaces the values in the receiver at the locations given by the