diff --git a/CHANGELOG.md b/CHANGELOG.md
index d8f52de..ede2448 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,5 @@
 ## Next version
 
- * We now support multiple versions of native extension gems. For example, we now supply Nokogiri 1.5 and 1.6.
  * Fixed the mysql2 native extension not working on Linux. This is done by dynamically linking against libstdc++. Closes GH-21.
 
 ## Version 20141219
diff --git a/linux/build b/linux/build
index e862c1e..3738189 100755
--- a/linux/build
+++ b/linux/build
@@ -11,7 +11,7 @@ RUNTIME_DIR=
 OUTPUT_DIR=
 ARCHITECTURE=
 CONCURRENCY=$CPUCOUNT
-GEMFILE="$SELFDIR/../shared/gemfiles"
+GEMFILE="$SELFDIR/../shared/Gemfile"
 SETUP_SOURCE=true
 COMPILE=true
 SANITY_CHECK_OUTPUT=true
@@ -101,20 +101,9 @@ if [[ ! -e "$RUNTIME_DIR/mock" ]]; then
 fi
 if [[ "$GEMFILE" != "" ]]; then
 	GEMFILE="`absolute_path \"$GEMFILE\"`"
-	if [[ -d "$GEMFILE" ]]; then
-		for F in "$GEMFILE"/*/Gemfile; do
-			DIR="`dirname \"$F\"`"
-			DIR="`basename \"$DIR\"`"
-			GEMFILE_MOUNT+=(-v "$F:/gemfiles/$DIR/Gemfile:ro")
-			if [[ -e "$F.lock" ]]; then
-				GEMFILE_MOUNT+=(-v "$F.lock:/gemfiles/$DIR/Gemfile.lock:ro")
-			fi
-		done
-	else
-		GEMFILE_MOUNT=(-v "$GEMFILE:/gemfiles/Gemfile:ro")
-		if [[ -e "$GEMFILE.lock" ]]; then
-			GEMFILE_MOUNT+=(-v "$GEMFILE.lock:/gemfiles/Gemfile.lock:ro")
-		fi
+	GEMFILE_MOUNT=(-v "$GEMFILE:/Gemfile:ro")
+	if [[ -e "$GEMFILE.lock" ]]; then
+		GEMFILE_MOUNT+=(-v "$GEMFILE.lock:/Gemfile.lock:ro")
 	fi
 fi
 
diff --git a/linux/internal/build b/linux/internal/build
index 6e9f5cd..0abdfb2 100755
--- a/linux/internal/build
+++ b/linux/internal/build
@@ -12,9 +12,12 @@ ROOT=/var/lib/mock/$CHROOT_NAME/root
 run rm -rf $ROOT/system $ROOT/output
 run mkdir $ROOT/system $ROOT/output
 run cp /system/* $ROOT/system/
-run cp -R /system_shared/* $ROOT/system/
-if [[ -e /gemfiles ]]; then
-	run cp -R /gemfiles $ROOT/system/
+run cp /system_shared/* $ROOT/system/
+if [[ -e /Gemfile ]]; then
+	run cp /Gemfile $ROOT/system/
+fi
+if [[ -e /Gemfile.lock ]]; then
+	run cp /Gemfile.lock $ROOT/system/
 fi
 echo "Dumping parameters"
 echo $ARCHITECTURE > $ROOT/system/NAME
diff --git a/linux/internal/build-inside-mock b/linux/internal/build-inside-mock
index 1f2858c..79dade0 100755
--- a/linux/internal/build-inside-mock
+++ b/linux/internal/build-inside-mock
@@ -172,21 +172,15 @@ echo $GEM_EXTENSION_API_VERSION > /tmp/ruby/info/GEM_EXTENSION_API_VERSION
 # removing explicitly gems.
 run rm -rf /tmp/ruby/lib/ruby/gems/$RUBY_COMPAT_VERSION/gems/{test-unit,rdoc}-*
 
-if [[ -e /system/gemfiles ]]; then
+if [[ -e /system/Gemfile ]]; then
 	run /tmp/ruby/bin/gem install bundler -v $BUNDLER_VERSION --no-rdoc --no-ri
-	
-	for GEMFILE in /system/gemfiles/*/Gemfile; do
-		run cp "$GEMFILE" /tmp/ruby/
-		if [[ -e "$GEMFILE.lock" ]]; then
-			run cp "$GEMFILE.lock" /tmp/ruby/
-		fi
-		echo "+ Entering /tmp/ruby"
-		pushd /tmp/ruby >/dev/null
-		run /tmp/ruby/bin/bundle install --system --retry 3
-		run rm Gemfile*
-		echo "+ Leaving /tmp/ruby"
-		popd >/dev/null
-	done
+	run cp /system/Gemfile* /tmp/ruby
+	echo "+ Entering /tmp/ruby"
+	pushd /tmp/ruby >/dev/null
+	run /tmp/ruby/bin/bundle install --system --retry 3
+	run rm Gemfile*
+	echo "+ Leaving /tmp/ruby"
+	popd >/dev/null
 fi
 
 # Strip binaries and remove unnecessary files.
diff --git a/linux/internal/setup-runtime b/linux/internal/setup-runtime
index 5e78ff4..490609a 100755
--- a/linux/internal/setup-runtime
+++ b/linux/internal/setup-runtime
@@ -50,7 +50,7 @@ header "Installing additional software inside chroot"
 run rm -rf /var/lib/mock/$CHROOT_NAME/root/system
 run mkdir /var/lib/mock/$CHROOT_NAME/root/system
 run cp /system/* /var/lib/mock/$CHROOT_NAME/root/system/
-run cp -R /system_shared/* /var/lib/mock/$CHROOT_NAME/root/system/
+run cp /system_shared/* /var/lib/mock/$CHROOT_NAME/root/system/
 echo $ARCHITECTURE > /var/lib/mock/$CHROOT_NAME/root/system/ARCHITECTURE
 run /system/setuser app /usr/bin/mock -r $CHROOT_NAME --shell /system/setup-runtime-inside-mock
 run rm -rf /var/lib/mock/$CHROOT_NAME/root/system
diff --git a/linux/internal/setup-runtime-inside-mock b/linux/internal/setup-runtime-inside-mock
index 30478ed..c2125be 100755
--- a/linux/internal/setup-runtime-inside-mock
+++ b/linux/internal/setup-runtime-inside-mock
@@ -26,8 +26,6 @@ export PATH=/usr/local/override/bin:$PATH
 CMAKE_VERSION=3.0.2
 OPENSSL_VERSION=1.0.1j
 FFI_VERSION=3.2.1
-LIBXML2_VERSION=2.9.2
-LIBXSLT_VERSION=1.1.28
 SQLITE3_VERSION=3080702
 MYSQL_LIB_VERSION=6.1.5
 POSTGRESQL_VERSION=9.3.5
@@ -104,48 +102,6 @@ if [[ ! -e /usr/local/override/lib/libffi.so.6 ]]; then
 fi
 echo
 
-header "Installing libxml2"
-if [[ ! -e /usr/local/override/lib/libxml2.a ]]; then
-	download_and_extract libxml2-$LIBXML2_VERSION.tar.gz \
-		ftp://xmlsoft.org/libxml2/libxml2-$LIBXML2_VERSION.tar.gz
-	echo "Entering libxml2-$LIBXML2_VERSION"
-	pushd libxml2-$LIBXML2_VERSION >/dev/null
-
-	run ./configure --prefix=/usr/local/override --disable-shared \
-		--without-debug --without-docbook --without-fexceptions \
-		--without-ftp --without-http --without-history --without-mem-debug \
-		--without-python --without-readline --with-c14n \
-		--with-threads CFLAGS='-fPIC -fvisibility=hidden'
-	run make -j$CONCURRENCY
-	run make install-strip
-
-	echo "Leaving source directory"
-	popd >/dev/null
-	run rm -rf libxml2-$LIBXML2_VERSION
-fi
-echo
-
-header "Installing libxslt"
-if [[ ! -e /usr/local/override/lib/libxslt.a ]]; then
-	download_and_extract libxslt-$LIBXSLT_VERSION.tar.gz \
-		ftp://xmlsoft.org/libxml2/libxslt-$LIBXSLT_VERSION.tar.gz
-	echo "Entering libxslt-$LIBXSLT_VERSION"
-	pushd libxslt-$LIBXSLT_VERSION >/dev/null
-
-	run ./configure --prefix=/usr/local/override --disable-shared \
-		--without-python --without-crypto --without-debug \
-		--without-mem-debug --without-debugger \
-		CFLAGS='-fPIC -fvisibility=hidden'
-	run make -j$CONCURRENCY
-	run make install-strip
-
-	echo "Leaving source directory"
-	popd >/dev/null
-	run rm -rf libxslt-$LIBXSLT_VERSION
-fi
-echo
-
-header "Installing SQLite3"
 if [[ ! -e /usr/local/override/lib/libsqlite3.a ]]; then
 	download_and_extract sqlite-autoconf-$SQLITE3_VERSION.tar.gz \
 		http://www.sqlite.org/2014/sqlite-autoconf-$SQLITE3_VERSION.tar.gz
diff --git a/osx/build b/osx/build
index ce1ea04..e9a2aae 100755
--- a/osx/build
+++ b/osx/build
@@ -9,12 +9,11 @@ BUNDLER_VERSION=`cat "$SELFDIR/../BUNDLER_VERSION.txt"`
 
 WORKDIR=
 OWNS_WORKDIR=true
-GEMFILES=()
 
 RUNTIME_DIR=
 OUTPUT_DIR=
 CONCURRENCY=4
-GEMFILE="$SELFDIR/../shared/gemfiles"
+GEMFILE="$SELFDIR/../shared/Gemfile"
 SETUP_SOURCE=true
 COMPILE=true
 
@@ -177,11 +176,6 @@ else
 fi
 if [[ "$GEMFILE" != "" ]]; then
 	GEMFILE="`absolute_path \"$GEMFILE\"`"
-	if [[ -d "$GEMFILE" ]]; then
-		GEMFILES=("$GEMFILE"/*/Gemfile)
-	else
-		GEMFILES=("$GEMFILE")
-	fi
 fi
 
 
@@ -274,29 +268,25 @@ if [[ "$GEMFILE" != "" ]]; then
 		run /tmp/ruby/bin/gem install "$RUNTIME_DIR/vendor/cache/bundler-$BUNDLER_VERSION.gem" --no-rdoc --no-ri
 	else
 		run /tmp/ruby/bin/gem install bundler -v $BUNDLER_VERSION --no-rdoc --no-ri
-		run mkdir -p "$RUNTIME_DIR/vendor/cache"
-		run cp /tmp/ruby/lib/ruby/gems/$RUBY_COMPAT_VERSION/cache/bundler-$BUNDLER_VERSION.gem "$RUNTIME_DIR/vendor/cache/"
 	fi
 
 	# Run bundle install.
-	for GEMFILE in "${GEMFILES[@]}"; do
-		run cp "$GEMFILE" /tmp/ruby/
-		if [[ -e "$GEMFILE.lock" ]]; then
-			run cp "$GEMFILE.lock" /tmp/ruby/
-		fi
-		echo "+ Entering /tmp/ruby"
-		pushd /tmp/ruby >/dev/null
-		run /tmp/ruby/bin/bundle config --local build.nokogiri ""
-		run /tmp/ruby/bin/bundle config --local build.mysql2 "--with-mysql_config"
-		run /tmp/ruby/bin/bundle install --system --retry 3
-		run /tmp/ruby/bin/bundle package
-		run rm -rf "$RUNTIME_DIR/vendor"
-		run mv vendor "$RUNTIME_DIR/"
-		
-		run rm -rf Gemfile* .bundle
-		echo "+ Leaving /tmp/ruby"
-		popd >/dev/null
-	done
+	run cp "$GEMFILE" /tmp/ruby/
+	if [[ -e "$GEMFILE.lock" ]]; then
+		run cp "$GEMFILE.lock" /tmp/ruby/
+	fi
+	echo "+ Entering /tmp/ruby"
+	pushd /tmp/ruby >/dev/null
+	run /tmp/ruby/bin/bundle config --local build.nokogiri ""
+	run /tmp/ruby/bin/bundle config --local build.mysql2 "--with-mysql_config"
+	run /tmp/ruby/bin/bundle install --system --retry 3
+	run /tmp/ruby/bin/bundle package
+	run rm -rf "$RUNTIME_DIR/vendor"
+	run mv vendor "$RUNTIME_DIR/"
+	run cp /tmp/ruby/lib/ruby/gems/$RUBY_COMPAT_VERSION/cache/bundler-$BUNDLER_VERSION.gem "$RUNTIME_DIR/vendor/cache/"
+	run rm -rf Gemfile* .bundle
+	echo "+ Leaving /tmp/ruby"
+	popd >/dev/null
 fi
 
 # Strip binaries and remove unnecessary files.
diff --git a/osx/setup-runtime b/osx/setup-runtime
index 6d2bbc3..acd6cf8 100755
--- a/osx/setup-runtime
+++ b/osx/setup-runtime
@@ -26,10 +26,6 @@ FORCE_LIBFFI=false
 SKIP_LIBFFI=false
 FORCE_LIBYAML=false
 SKIP_LIBYAML=false
-FORCE_LIBXML2=false
-SKIP_LIBXML2=false
-FORCE_LIBXSLT=false
-SKIP_LIBXSL=false
 FORCE_SQLITE3=false
 SKIP_SQLITE3=false
 FORCE_LIBLZMA=false
@@ -180,7 +176,7 @@ RUNTIME_DIR="`cd \"$RUNTIME_DIR\" && pwd`"
 #######################################
 
 
-TOTAL_LIBS=12
+TOTAL_LIBS=10
 RUBY_MAJOR_MINOR=2.1
 RUBY_VERSION=2.1.5
 CMAKE_VERSION=3.0.2
@@ -192,8 +188,6 @@ GMP_VERSION=6.0.0a
 GMP_DIR_VERSION=6.0.0
 LIBFFI_VERSION=3.2.1
 LIBYAML_VERSION=0.1.5
-LIBXML2_VERSION=2.9.2
-LIBXSLT_VERSION=1.1.28
 SQLITE3_VERSION=3080702
 XZ_VERSION=5.0.7
 MYSQL_LIB_VERSION=6.1.5
@@ -236,8 +230,7 @@ elif [[ ! -e "$RUNTIME_DIR/bin/cmake" ]] || $FORCE_CMAKE; then
 	run ./configure --prefix="$RUNTIME_DIR" --no-qt-gui --parallel=$CONCURRENCY
 	run make -j$CONCURRENCY
 	run make install
-
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf cmake-$CMAKE_VERSION
 else
@@ -259,8 +252,7 @@ elif [[ ! -e "$RUNTIME_DIR/bin/openssl" ]] || $FORCE_OPENSSL; then
 		threads zlib shared no-sse2
 	run make
 	run make install_sw
-
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf openssl-$OPENSSL_VERSION
 
@@ -298,8 +290,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/libncurses.5.dylib" ]] || $FORCE_NCURSES; then
 		--without-develop
 	run make -j$CONCURRENCY
 	run make install
-	
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf ncurses-$NCURSES_VERSION
 
@@ -330,8 +321,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/libedit.0.dylib" ]] || $FORCE_LIBEDIT; then
 	run ./configure --prefix="$RUNTIME_DIR" --disable-static --enable-widec
 	run make -j$CONCURRENCY
 	run make install-strip
-	
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf libedit-$LIBEDIT_DIR_VERSION
 
@@ -359,8 +349,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/libgmp.10.dylib" ]] || $FORCE_GMP; then
 	run ./configure --prefix="$RUNTIME_DIR" --disable-static --without-readline
 	run make -j$CONCURRENCY
 	run make install-strip
-	
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf gmp-$GMP_DIR_VERSION
 
@@ -386,8 +375,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/libffi.6.dylib" ]] || $FORCE_LIBFFI; then
 		./configure --prefix="$RUNTIME_DIR" --disable-static --enable-portable-binary
 	run make -j$CONCURRENCY
 	run make install-strip
-	
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf libffi-$LIBFFI_VERSION
 
@@ -410,8 +398,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/libyaml-0.2.dylib" ]] || $FORCE_LIBYAML; then
 	run ./configure --prefix="$RUNTIME_DIR" --disable-static
 	run make -j$CONCURRENCY
 	run make install-strip
-	
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf yaml-$LIBYAML_VERSION
 
@@ -422,56 +409,7 @@ else
 fi
 echo
 
-header "Compiling runtime libraries 7/$TOTAL_LIBS: libxml2..."
-if $SKIP_LIBXML2; then
-	echo "Skipped."
-elif [[ ! -e "$RUNTIME_DIR/lib/libxml2.a" ]] || $FORCE_LIBXML2; then
-	download_and_extract libxml2-$LIBXML2_VERSION.tar.gz \
-		ftp://xmlsoft.org/libxml2/libxml2-$LIBXML2_VERSION.tar.gz
-	echo "Entering $RUNTIME_DIR/libxml2-$LIBXML2_VERSION"
-	pushd libxml2-$LIBXML2_VERSION >/dev/null
-
-	run ./configure --prefix="$RUNTIME_DIR" --disable-shared \
-		--without-debug --without-docbook --without-fexceptions \
-		--without-ftp --without-http --without-history --without-mem-debug \
-		--without-python --without-readline --with-c14n \
-		--with-threads CFLAGS='-fPIC -fvisibility=hidden'
-	run make -j$CONCURRENCY
-	run make install-strip
-
-	echo "Leaving source directory"
-	popd >/dev/null
-	run rm -rf libxml2-$LIBXML2_VERSION
-else
-	echo "Already installed."
-fi
-echo
-
-header "Compiling runtime libraries 8/$TOTAL_LIBS: libxslt..."
-if $SKIP_LIBXSLT; then
-	echo "Skipped."
-elif [[ ! -e "$RUNTIME_DIR/lib/libxslt.a" ]] || $FORCE_LIBXSLT; then
-	download_and_extract libxslt-$LIBXSLT_VERSION.tar.gz \
-		ftp://xmlsoft.org/libxml2/libxslt-$LIBXSLT_VERSION.tar.gz
-	echo "Entering libxslt-$LIBXSLT_VERSION"
-	pushd libxslt-$LIBXSLT_VERSION >/dev/null
-
-	run ./configure --prefix=/usr/local/override --disable-shared \
-		--without-python --without-crypto --without-debug \
-		--without-mem-debug --without-debugger \
-		CFLAGS='-fPIC -fvisibility=hidden'
-	run make -j$CONCURRENCY
-	run make install-strip
-
-	echo "Leaving source directory"
-	popd >/dev/null
-	run rm -rf libxslt-$LIBXSLT_VERSION
-else
-	echo "Already installed."
-fi
-echo
-
-header "Compiling runtime libraries 9/$TOTAL_LIBS: sqlite3..."
+header "Compiling runtime libraries 7/$TOTAL_LIBS: sqlite3..."
 if $SKIP_SQLITE3; then
 	echo "Skipped."
 elif [[ ! -e "$RUNTIME_DIR/lib/libsqlite3.a" ]] || $FORCE_SQLITE3; then
@@ -492,7 +430,7 @@ else
 fi
 echo
 
-header "Compiling runtime libraries 10/$TOTAL_LIBS: liblzma..."
+header "Compiling runtime libraries 8/$TOTAL_LIBS: liblzma..."
 if $SKIP_LIBLZMA; then
 	echo "Skipped."
 elif [[ ! -e "$RUNTIME_DIR/lib/liblzma.5.dylib" ]] || $FORCE_LIBLZMA; then
@@ -507,7 +445,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/liblzma.5.dylib" ]] || $FORCE_LIBLZMA; then
 	run make -j$CONCURRENCY
 	run make install-strip
 
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf xz-$XZ_VERSION
 
@@ -518,7 +456,7 @@ else
 fi
 echo
 
-header "Compiling runtime libraries 11/$TOTAL_LIBS: MySQL..."
+header "Compiling runtime libraries 9/$TOTAL_LIBS: MySQL..."
 if $SKIP_MYSQL; then
 	echo "Skipped."
 elif [[ ! -e "$RUNTIME_DIR/lib/libmysqlclient.a" ]] || $FORCE_MYSQL; then
@@ -542,7 +480,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/libmysqlclient.a" ]] || $FORCE_MYSQL; then
 	run make -C include install
 	run make -C scripts install
 
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf mysql-connector-c-$MYSQL_LIB_VERSION-src
 else
@@ -550,7 +488,7 @@ else
 fi
 echo
 
-header "Compiling runtime libraries 12/$TOTAL_LIBS: PostgreSQL..."
+header "Compiling runtime libraries 10/$TOTAL_LIBS: PostgreSQL..."
 if $SKIP_POSTGRESQL; then
 	echo "Skipped."
 elif [[ ! -e "$RUNTIME_DIR/lib/libpq.a" ]] || $FORCE_POSTGRESQL; then
@@ -569,7 +507,7 @@ elif [[ ! -e "$RUNTIME_DIR/lib/libpq.a" ]] || $FORCE_POSTGRESQL; then
 	run make -j$CONCURRENCY -C src/bin/pg_config
 	run make -C src/bin/pg_config install-strip
 
-	echo "Leaving source directory"
+	echo "Entering $RUNTIME_DIR"
 	popd >/dev/null
 	run rm -rf postgresql-$POSTGRESQL_VERSION
 
diff --git a/shared/gemfiles/default/Gemfile b/shared/Gemfile
similarity index 100%
rename from shared/gemfiles/default/Gemfile
rename to shared/Gemfile
diff --git a/shared/gemfiles/default/Gemfile.lock b/shared/Gemfile.lock
similarity index 100%
rename from shared/gemfiles/default/Gemfile.lock
rename to shared/Gemfile.lock
diff --git a/shared/gemfiles/nokogiri-1.5/Gemfile b/shared/gemfiles/nokogiri-1.5/Gemfile
deleted file mode 100644
index 47fac78..0000000
--- a/shared/gemfiles/nokogiri-1.5/Gemfile
+++ /dev/null
@@ -1,4 +0,0 @@
-#source 'http://production.cf.rubygems.org/'
-source 'https://rubygems.org'
-
-gem 'nokogiri', '~> 1.5.0'
diff --git a/shared/gemfiles/nokogiri-1.5/Gemfile.lock b/shared/gemfiles/nokogiri-1.5/Gemfile.lock
deleted file mode 100644
index cbec8be..0000000
--- a/shared/gemfiles/nokogiri-1.5/Gemfile.lock
+++ /dev/null
@@ -1,10 +0,0 @@
-GEM
-  remote: https://rubygems.org/
-  specs:
-    nokogiri (1.5.11)
-
-PLATFORMS
-  ruby
-
-DEPENDENCIES
-  nokogiri (~> 1.5.0)