diff --git a/imagefiles/build-and-install-curl.sh b/imagefiles/build-and-install-curl.sh
index c015c05..4086bd4 100755
--- a/imagefiles/build-and-install-curl.sh
+++ b/imagefiles/build-and-install-curl.sh
@@ -2,8 +2,11 @@
 
 set -ex
 
-MY_DIR=$(dirname "${BASH_SOURCE[0]}")
-source $MY_DIR/utils.sh
+# Get script directory
+SCRIPT_DIR=$(dirname "${BASH_SOURCE[0]}")
+
+# Get build utilities
+source $SCRIPT_DIR/utils.sh
 
 #
 # Function 'do_curl_build' and 'build_curl'
@@ -20,6 +23,7 @@ if [[ -z "${CURL_HASH}" ]]; then
   exit 1
 fi
 
+CURL_ROOT="${CURL_VERSION}"
 CURL_DOWNLOAD_URL=https://curl.haxx.se/download
 
 function do_curl_build {
@@ -30,28 +34,16 @@ function do_curl_build {
     make install > /dev/null
 }
 
-
-function build_curl {
-    local curl_fname=$1
-    check_var ${curl_fname}
-    local curl_sha256=$2
-    check_var ${curl_sha256}
-    check_var ${CURL_DOWNLOAD_URL}
-    curl --connect-timeout 30 \
-        --max-time 10 \
-        --retry 5 \
-        --retry-delay 10 \
-        --retry-max-time 30 \
-        -fsSLO ${CURL_DOWNLOAD_URL}/${curl_fname}.tar.gz
-
-    check_sha256sum ${curl_fname}.tar.gz ${curl_sha256}
-    tar -zxf ${curl_fname}.tar.gz
-    (cd curl-*/ && do_curl_build)
-    rm -rf curl-*
-}
-
 cd /usr/src
-build_curl "${CURL_VERSION}" "${CURL_HASH}"
+
+fetch_source "${CURL_ROOT}.tar.gz" "${CURL_DOWNLOAD_URL}"
+check_sha256sum "${CURL_ROOT}.tar.gz" "${CURL_HASH}"
+
+tar -zxf "${CURL_ROOT}.tar.gz"
+pushd "${CURL_ROOT}"
+do_curl_build
+popd
+rm -rf "${CURL_ROOT}" "${CURL_ROOT}.tar.gz"
 
 (cat /etc/ld.so.conf.d/usr-local.conf 2> /dev/null | grep -q "^/usr/local/lib$") ||
   echo '/usr/local/lib' >> /etc/ld.so.conf.d/usr-local.conf
diff --git a/imagefiles/build-and-install-git.sh b/imagefiles/build-and-install-git.sh
index 662dbe1..4d95f46 100755
--- a/imagefiles/build-and-install-git.sh
+++ b/imagefiles/build-and-install-git.sh
@@ -2,10 +2,12 @@
 
 set -ex
 
-if ! command -v curl &> /dev/null; then
-	echo >&2 'error: "curl" not found!'
-	exit 1
-fi
+# Get script directory
+SCRIPT_DIR=$(dirname "${BASH_SOURCE[0]}")
+
+# Get build utilities
+source $SCRIPT_DIR/utils.sh
+
 
 if ! command -v tar &> /dev/null; then
 	echo >&2 'error: "tar" not found!'
@@ -23,27 +25,20 @@ ldconfig
 
 cd /usr/src
 
-url="https://mirrors.edge.kernel.org/pub/software/scm/git/git-${GIT_VERSION}.tar.gz"
-echo "Downloading $url"
-curl --connect-timeout 20 \
-    --max-time 10 \
-    --retry 5 \
-    --retry-delay 10 \
-    --retry-max-time 40 \
-    -# -LO $url
+GIT_ROOT="git-${GIT_VERSION}"
+GIT_DOWNLOAD_URL="https://mirrors.edge.kernel.org/pub/software/scm/git"
 
-tar xvzf "git-${GIT_VERSION}.tar.gz" --no-same-owner
-rm -f "git-${GIT_VERSION}.tar.gz"
+fetch_source "${GIT_ROOT}.tar.gz" "${GIT_DOWNLOAD_URL}"
+tar xvzf "${GIT_ROOT}.tar.gz" --no-same-owner
 
-pushd "git-${GIT_VERSION}"
+pushd "${GIT_ROOT}"
 ./configure --prefix=/usr/local --with-curl
 make -j"$(nproc)"
 make install
 popd
+rm -rf "${GIT_ROOT}" "${GIT_ROOT}.tar.gz"
 
 ldconfig
 
-rm -rf "git-${GIT_VERSION}"
-
 # turn the detached message off
 git config --global advice.detachedHead false
diff --git a/imagefiles/build-and-install-ninja.sh b/imagefiles/build-and-install-ninja.sh
index 64d3b68..a19a9f2 100755
--- a/imagefiles/build-and-install-ninja.sh
+++ b/imagefiles/build-and-install-ninja.sh
@@ -10,6 +10,12 @@
 set -e
 set -o pipefail
 
+# Get script directory
+SCRIPT_DIR=$(dirname "${BASH_SOURCE[0]}")
+
+# Get build utilities
+source $SCRIPT_DIR/utils.sh
+
 PYTHON=python
 while [ $# -gt 0 ]; do
   case "$1" in
@@ -31,25 +37,22 @@ if [[ -z "${NINJA_VERSION}" ]]; then
 fi
 
 # Download
-url="https://github.com/ninja-build/ninja/archive/v${NINJA_VERSION}.tar.gz"
+NINJA_DOWNLOAD_URL="https://github.com/ninja-build/ninja/archive/"
+NINJA_ROOT="v${NINJA_VERSION}"
 
-curl --connect-timeout 30 \
-    --max-time 10 \
-    --retry 5 \
-    --retry-delay 10 \
-    --retry-max-time 30 \
-    -# -o ninja.tar.gz -LO "$url"
+fetch_source "${NINJA_ROOT}.tar.gz" "${NINJA_DOWNLOAD_URL}"
 
-mkdir ninja
-tar -xzvf ./ninja.tar.gz --strip-components=1 -C ./ninja
+# Since the archive name doesn't match the top-level directory, explicitly specify it.
+mkdir -p "${NINJA_ROOT}"
+tar xvzf "${NINJA_ROOT}.tar.gz"  --strip-components=1 -C "${NINJA_ROOT}"
 
 # Configure, build and install
-pushd ./ninja
+pushd "${NINJA_ROOT}"
 echo "Configuring ninja using [$PYTHON]"
 $PYTHON ./configure.py --bootstrap && ./ninja
 cp ./ninja /usr/bin/
 popd
 
 # Clean
-rm -rf ./ninja*
+rm -rf "${NINJA_ROOT}" "${NINJA_ROOT}.tar.gz"
 
diff --git a/imagefiles/build-and-install-openssl.sh b/imagefiles/build-and-install-openssl.sh
index 8df66c2..76e7e0b 100755
--- a/imagefiles/build-and-install-openssl.sh
+++ b/imagefiles/build-and-install-openssl.sh
@@ -39,8 +39,11 @@ while [ $# -gt 0 ]; do
   shift
 done
 
-MY_DIR=$(dirname "${BASH_SOURCE[0]}")
-source $MY_DIR/utils.sh
+# Get script directory
+SCRIPT_DIR=$(dirname "${BASH_SOURCE[0]}")
+
+# Get build utilities
+source $SCRIPT_DIR/utils.sh
 
 #
 # Function 'do_openssl_build' and 'build_openssl'
@@ -84,13 +87,8 @@ function build_perl {
     local perl_sha256=$2
     check_var ${perl_sha256}
     check_var ${PERL_DOWNLOAD_URL}
-    curl --connect-timeout 30 \
-        --max-time 10 \
-        --retry 5 \
-        --retry-delay 10 \
-        --retry-max-time 30 \
-        -fsSLO ${PERL_DOWNLOAD_URL}/${perl_fname}.tar.gz
 
+    fetch_source "${perl_fname}.tar.gz" "${PERL_DOWNLOAD_URL}"
     check_sha256sum ${perl_fname}.tar.gz ${perl_sha256}
     tar -xzf ${perl_fname}.tar.gz --no-same-owner
     (cd ${perl_fname} && do_perl_build)
@@ -109,13 +107,8 @@ function build_openssl {
     local openssl_sha256=$2
     check_var ${openssl_sha256}
     check_var ${OPENSSL_DOWNLOAD_URL}
-    curl --connect-timeout 30 \
-        --max-time 10 \
-        --retry 5 \
-        --retry-delay 10 \
-        --retry-max-time 30 \
-        -fsSLO ${OPENSSL_DOWNLOAD_URL}/${openssl_fname}.tar.gz
 
+    fetch_source "${openssl_fname}.tar.gz" "${OPENSSL_DOWNLOAD_URL}"
     check_sha256sum ${openssl_fname}.tar.gz ${openssl_sha256}
     tar -xzf ${openssl_fname}.tar.gz
     (cd ${openssl_fname} && PATH=/opt/perl/bin:${PATH} do_openssl_build)
diff --git a/imagefiles/install-cmake-binary.sh b/imagefiles/install-cmake-binary.sh
index 35113d1..61fed0b 100755
--- a/imagefiles/install-cmake-binary.sh
+++ b/imagefiles/install-cmake-binary.sh
@@ -3,6 +3,12 @@
 set -ex
 set -o pipefail
 
+# Get script directory
+SCRIPT_DIR=$(dirname "${BASH_SOURCE[0]}")
+
+# Get build utilities
+source $SCRIPT_DIR/utils.sh
+
 ARCH="x86_64"
 
 while [ $# -gt 0 ]; do
@@ -18,11 +24,6 @@ while [ $# -gt 0 ]; do
   shift
 done
 
-if ! command -v curl &> /dev/null; then
-	echo >&2 'error: "curl" not found!'
-	exit 1
-fi
-
 if ! command -v tar &> /dev/null; then
 	echo >&2 'error: "tar" not found!'
 	exit 1
@@ -35,16 +36,12 @@ fi
 
 cd /usr/src
 
-CMAKE_ROOT=cmake-${CMAKE_VERSION}-Centos5-${ARCH}
-url=https://github.com/dockbuild/CMake/releases/download/v${CMAKE_VERSION}/${CMAKE_ROOT}.tar.gz
-echo "Downloading $url"
-curl --connect-timeout 30 \
-    --max-time 10 \
-    --retry 5 \
-    --retry-delay 10 \
-    --retry-max-time 30 \
-    -# -LO $url
+CMAKE_ROOT=cmake-${CMAKE_VERSION}-linux-${ARCH}
+CMAKE_DOWNLOAD_URL=https://github.com/Kitware/CMake/releases/download/v${CMAKE_VERSION}
 
+echo "Downloading ${CMAKE_DOWNLOAD_URL}/${CMAKE_ROOT}.tar.gz"
+
+fetch_source "${CMAKE_ROOT}.tar.gz" "${CMAKE_DOWNLOAD_URL}"
 tar -xzvf "${CMAKE_ROOT}.tar.gz"
 rm -f "${CMAKE_ROOT}.tar.gz"
 
diff --git a/imagefiles/utils.sh b/imagefiles/utils.sh
index 52fa08e..a30c264 100644
--- a/imagefiles/utils.sh
+++ b/imagefiles/utils.sh
@@ -22,3 +22,20 @@ function check_sha256sum {
     rm -f ${fname}.sha256
 }
 
+function fetch_source {
+    if ! command -v curl &> /dev/null; then
+      echo >&2 'error: "curl" not found!'
+      exit 1
+    fi
+    local file=$1
+    check_var "${file}"
+    local url=$2
+    check_var "${url}"
+    curl --fail \
+         --location \
+         --silent \
+         --show-error \
+         --connect-timeout 30 --max-time 10 \
+         --retry 5 --retry-delay 10 --retry-max-time 30 \
+         -o "${file}" ${url}/${file}
+}