diff --git a/build.sh b/build.sh
index 6b93c25abd2..4a0fe67297b 100755
--- a/build.sh
+++ b/build.sh
@@ -303,6 +303,10 @@ while [[ $# -gt 0 ]]; do
         VALGRIND="-DENABLE_VALGRIND_SH=1"
         ;;
 
+    -y | -Y)
+        ALWAYS_YES=1
+        ;;
+
     *)
         echo "Unknown option $1"
         PRINT_USAGE
@@ -375,10 +379,26 @@ if [[ ${#_VERBOSE} > 0 ]]; then
 fi
 
 # if LTO build is enabled and cc-toolchain/clang was compiled, use it instead
-if [[ $HAS_LTO == 1 && -f cc-toolchain/build/bin/clang++ ]]; then
-    SELF=`pwd`
-    _CXX="$SELF/cc-toolchain/build/bin/clang++"
-    _CC="$SELF/cc-toolchain/build/bin/clang"
+if [[ $HAS_LTO == 1 ]]; then
+    if [[ -f cc-toolchain/build/bin/clang++ ]]; then
+        SELF=`pwd`
+        _CXX="$CHAKRACORE_DIR/cc-toolchain/build/bin/clang++"
+        _CC="$CHAKRACORE_DIR/cc-toolchain/build/bin/clang"
+    else
+        # Linux LD possibly doesn't support LLVM LTO, check.. and compile clang if not
+        if [[ $OS_LINUX == 1 ]]; then
+            if [[ ! `ld -v` =~ 'GNU gold' ]]; then
+                $CHAKRACORE_DIR/tools/compile_clang.sh
+                if [[ $? != 0 ]]; then
+                  echo -e "tools/compile_clang.sh has failed.\n"
+                  echo "Try with 'sudo' ?"
+                  exit 1
+                fi
+                _CXX="$CHAKRACORE_DIR/cc-toolchain/build/bin/clang++"
+                _CC="$CHAKRACORE_DIR/cc-toolchain/build/bin/clang"
+            fi
+        fi
+    fi
 fi
 
 if [ "${HAS_LTO}${OS_LINUX}" == "11" ]; then
diff --git a/tools/XPlatInstall/install_ch.sh b/tools/XPlatInstall/install_ch.sh
index 49f5ef2fcdb..52a950787c6 100755
--- a/tools/XPlatInstall/install_ch.sh
+++ b/tools/XPlatInstall/install_ch.sh
@@ -52,7 +52,6 @@ GET_OS()
     exit
 }
 
-
 GET_LATEST()
 {
     GET_OS
@@ -61,12 +60,13 @@ GET_LATEST()
     CHAKRA_VERSION=$(curl -k -s -SL "https://aka.ms/chakracore/version")
 
     if [[ "$CHAKRA_VERSION" == *"Error"* ]]; then
-        PRINT $ERROR_COLOR "] Download Failed. Do you have an Internet connection?"
+        PRINT $ERROR_COLOR "] Please ensure you are connected to the internet and try again."
         exit 1
     fi
 
     PRINT $SUCCESS_COLOR "] Found ChakraCore ${CHAKRA_VERSION//_/.} for ${CURRENT_OS}"
-    BINARY_NAME="https://aka.ms/chakracore/${BINARY_NAME}_${CHAKRA_VERSION}.tar.gz"
+    BINARY_NAME="https://aka.ms/chakracore/${BINARY_NAME}_${CHAKRA_VERSION}"
+    SHASUM_NAME="${BINARY_NAME}_s"
 }
 
 PRINT $DEFAULT_COLOR "ChakraCore Installation Script 0.1b\n"
@@ -75,11 +75,11 @@ PRINT $DEFAULT_COLOR "Visit https://aka.ms/WhatIs/ChakraCore for more informatio
 GET_LATEST
 
 PRINT $DEFAULT_COLOR "----------------------------------------------------------------"
-PRINT $SUCCESS_COLOR   "\nThis script will download ChakraCore from"
-PRINT $DEFAULT_COLOR "${BINARY_NAME}\n"
+PRINT $SUCCESS_COLOR   "\nThis script will download & execute ChakraCore binary"
+PRINT $DEFAULT_COLOR "located at ${BINARY_NAME}\n"
 PRINT $DEFAULT_COLOR "----------------------------------------------------------------"
 PRINT $DEFAULT_COLOR "If you don't agree, press Ctrl+C to terminate"
-read -t 10 -p "Hit ENTER to continue (or wait 10 seconds)"
+read -t 20 -p "Hit ENTER to continue (or wait 20 seconds)"
 
 if [ -d "./ChakraCoreFiles" ]; then
     PRINT $ERROR_COLOR "] Found 'ChakraCoreFiles' folder on the current path."
@@ -87,29 +87,65 @@ if [ -d "./ChakraCoreFiles" ]; then
     exit 1
 fi
 
+CHECK_DOWNLOAD_FAIL()
+{
+    if [[ $? != 0 ]]; then
+        PRINT $ERROR_COLOR "] Download failed."
+        PRINT $DEFAULT_COLOR "] ${___}"
+        exit 1
+    fi
+}
+
 PRINT $DEFAULT_COLOR "\n] Downloading ChakraCore"
 PRINT $SUCCESS_COLOR "] ${BINARY_NAME}"
-
 ___=$(curl -kSL -o "chakracore.tar.gz" "${BINARY_NAME}" 2>&1)
+CHECK_DOWNLOAD_FAIL
 
-if [[ $? != 0 ]]; then
-    PRINT $ERROR_COLOR "] Download failed."
-    PRINT $DEFAULT_COLOR "] ${___}"
-    exit 1
-fi
+PRINT $DEFAULT_COLOR "\n] Downloading ChakraCore shasum"
+PRINT $SUCCESS_COLOR "] ${SHASUM_NAME}"
+___=$(curl -kSL -o "chakracore_s.tar.gz" "${SHASUM_NAME}" 2>&1)
+CHECK_DOWNLOAD_FAIL
 
 PRINT $SUCCESS_COLOR "] Download completed"
 
-___=$(tar -xzf chakracore.tar.gz 2>&1)
+CHECK_EXT_FAIL()
+{
+    if [[ $? != 0 ]]; then
+        PRINT $ERROR_COLOR "] Extracting the compressed file failed."
+        PRINT $DEFAULT_COLOR "] ${___}"
+        rm -rf ChakraCoreFiles/
+        rm -rf chakracore.tar.gz
+        rm -rf chakracore_s.tar.gz
+        exit 1
+    fi
+}
 
-if [[ $? != 0 ]]; then
-    PRINT $ERROR_COLOR "] Extracting the compressed file is failed."
-    PRINT $DEFAULT_COLOR "] ${___}"
-    rm -rf ChakraCoreFiles/
+___=$(tar -xzf chakracore_s.tar.gz 2>&1)
+CHECK_EXT_FAIL
+
+SUM1=`shasum -a 512256 chakracore.tar.gz`
+SUM2=`cat ChakraCoreFiles/shasum`
+SUM1="${SUM1}@"
+SUM2="${SUM2}@"
+
+if [[ ! $SUM1 =~ $SUM2 ]]; then
+    PRINT $ERROR_COLOR "] Corrupted binary package."
+    PRINT $DEFAULT_COLOR "] Check your network connection."
+    PRINT $ERROR_COLOR "] If you suspect there is some other problem,\
+ https://github.com/Microsoft/ChakraCore#contact-us"
     rm -rf chakracore.tar.gz
+    rm -rf chakracore_s.tar.gz
+    rm -rf ChakraCoreFiles/
     exit 1
 fi
 
+rm -rf chakracore_s.tar.gz
+
+PRINT $SUCCESS_COLOR "] ChakraCore package SHASUM matches"
+
+___=$(tar -xzf chakracore.tar.gz 2>&1)
+CHECK_EXT_FAIL
+
 rm -rf chakracore.tar.gz
 
 # test ch
diff --git a/tools/create_package.sh b/tools/create_package.sh
index 4fb15ee0c07..adf0a964f85 100755
--- a/tools/create_package.sh
+++ b/tools/create_package.sh
@@ -82,7 +82,7 @@ echo -e "\n***** Third Party Notices [ for PreBuilt Binaries ] *****\n" >> out/C
 cat tools/XPlatInstall/BINARY-DIST-ONLY-NOTICES.txt >> out/ChakraCoreFiles/LICENSE
 # sample
 cp "tools/XPlatInstall/sample/README.md"  out/ChakraCoreFiles/sample/README.md
-cp "tools/XPlatInstall/sample/Makefile.txt"   out/ChakraCoreFiles/sample/Makefile
+cp "tools/XPlatInstall/sample/Makefile"   out/ChakraCoreFiles/sample/Makefile
 cp "tools/XPlatInstall/sample/sample.cpp.txt" out/ChakraCoreFiles/sample/sample.cpp
 
 ## Test
@@ -97,7 +97,16 @@ IF_ERROR_EXIT $? "CH binary test failed"
 pushd out/ > /dev/null
 PACKAGE_FILE="cc_${HOST_OS}_x64_${CHAKRA_VERSION}.tar.gz"
 tar -czf "${PACKAGE_FILE}" ChakraCoreFiles/
+mkdir -p temp/ChakraCoreFiles/
+cp "${PACKAGE_FILE}" temp/chakracore.tar.gz
+cd temp
+SHASUM_FILE="cc_${HOST_OS}_x64_${CHAKRA_VERSION}_s.tar.gz"
+shasum -a 512256 chakracore.tar.gz > ChakraCoreFiles/shasum
+tar -czf "$SHASUM_FILE" ChakraCoreFiles
+mv $SHASUM_FILE ../
+cd ..
+rm -rf temp/
 popd > /dev/null
 
 ## Credits
-echo -e "\nPackage file is ready at ${GREEN_COLOR}${PACKAGE_FILE}${DEFAULT_COLOR}"
+echo -e "\nPackage & Shasum files are ready under ${GREEN_COLOR}out/${DEFAULT_COLOR}"