diff --git a/.editorconfig b/.editorconfig
new file mode 100644
index 0000000..21985b5
--- /dev/null
+++ b/.editorconfig
@@ -0,0 +1,10 @@
+root = true
+
+[*]
+indent_style = tab
+indent_size = tab
+tab_width = 4
+end_of_line = lf
+charset = utf-8
+trim_trailing_whitespace = false
+insert_final_newline = true
diff --git a/.travis.yml b/.travis.yml
index c707c47..f8c318a 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -18,6 +18,14 @@ test-extensions-job-template: &test-extensions-job-template
 
 jobs:
   include:
+    - stage: Pre-test checks
+      name: Check coding style
+      if: type = pull_request
+      language: go
+      go: '1.13'
+      before_script: GO111MODULE=on go install mvdan.cc/sh/v3/cmd/shfmt
+      script: shfmt -d -s -ln posix -i 0 -ci -kp install-php-extensions scripts/common scripts/travisci-test-extensions scripts/travisci-update-readme scripts/update-readme
+
     - <<: *test-extensions-job-template
       name: Test extensions on Alpine 3.7
       env: DOCKER_DISTRO=alpine3.7
diff --git a/install-php-extensions b/install-php-extensions
index b8742df..79cae45 100755
--- a/install-php-extensions
+++ b/install-php-extensions
@@ -13,7 +13,7 @@ set -o errexit
 set -o nounset
 
 # Reset the Internal Field Separator
-resetIFS () {
+resetIFS() {
 	IFS='	 
 '
 }
@@ -22,7 +22,7 @@ resetIFS () {
 #
 # Output:
 #   alpine|debian
-getDistro () {
+getDistro() {
 	getDistro_os_id=''
 	if test -r /etc/os-release; then
 		getDistro_os_id="$(cat /etc/os-release | grep -E ^ID= | cut -d = -f 2)"
@@ -35,7 +35,7 @@ getDistro () {
 # Example output:
 #   alpine@3.10
 #   debian@9
-getDistroVersion () {
+getDistroVersion() {
 	getDistroVersion_distro="$(getDistro)"
 	if test -z "$getDistroVersion_distro"; then
 		return
@@ -54,7 +54,7 @@ getDistroVersion () {
 #
 # Output:
 #   The PHP numeric Major-Minor version
-getPHPMajorMinor () {
+getPHPMajorMinor() {
 	php -r '$v = explode(".", PHP_VERSION); echo $v[0] * 100 + $v[1];'
 }
 
@@ -62,25 +62,24 @@ getPHPMajorMinor () {
 #
 # Output:
 #   Space-separated list of module handles
-getPHPInstalledModules () {
+getPHPInstalledModules() {
 	getPHPInstalledModules_result=''
 	IFS='
 '
 	for getPHPInstalledModules_module in $(php -m); do
 		getPHPInstalledModules_moduleNormalized=''
 		case "$getPHPInstalledModules_module" in
-			\[PHP\ Modules\])
-				;;
+			\[PHP\ Modules\]) ;;
 			\[Zend\ Modules\])
 				break
 				;;
-			Core|PDO|PDO_*|Phar|Reflection|SimpleXML|SPL|SQLite|Xdebug)
+			Core | PDO | PDO_* | Phar | Reflection | SimpleXML | SPL | SQLite | Xdebug)
 				getPHPInstalledModules_moduleNormalized=$(LC_CTYPE=C printf '%s' "$getPHPInstalledModules_module" | tr '[:upper:]' '[:lower:]')
 				;;
 			Zend\ OPcache)
 				getPHPInstalledModules_moduleNormalized='opcache'
 				;;
-			*\ *|*A*|*B*|*C*|*D*|*E*|*F*|*G*|*H*|*I*|*J*|*K*|*L*|*M*|*N*|*O*|*P*|*Q*|*R*|*S*|*T*|*U*|*V*|*W*|*X*|*Y*|*Z*)
+			*\ * | *A* | *B* | *C* | *D* | *E* | *F* | *G* | *H* | *I* | *J* | *K* | *L* | *M* | *N* | *O* | *P* | *Q* | *R* | *S* | *T* | *U* | *V* | *W* | *X* | *Y* | *Z*)
 				printf '### WARNING Unrecognized module name: %s ###\n' "$getPHPInstalledModules_module" >&2
 				;;
 			*)
@@ -107,7 +106,7 @@ getPHPInstalledModules () {
 #
 # Output:
 #   Nothing
-processCommandArguments () {
+processCommandArguments() {
 	processCommandArguments_alreadyInstalled="$(getPHPInstalledModules)"
 	processCommandArguments_endArgs=0
 	PHP_MODULES_TO_INSTALL=''
@@ -153,7 +152,7 @@ processCommandArguments () {
 #
 # Output:
 #   Nothing
-sortModulesToInstall () {
+sortModulesToInstall() {
 	if stringInList 'igbinary' "$PHP_MODULES_TO_INSTALL"; then
 		PHP_MODULES_TO_INSTALL="$(removeStringFromList 'igbinary' "$PHP_MODULES_TO_INSTALL")"
 		if test -z "$PHP_MODULES_TO_INSTALL"; then
@@ -185,7 +184,7 @@ sortModulesToInstall () {
 # Return:
 #   0 (true): if we to install some package
 #   1 (false): if no package is required
-buildRequiredPackageLists () {
+buildRequiredPackageLists() {
 	buildRequiredPackageLists_persistent=''
 	buildRequiredPackageLists_volatile=''
 	buildRequiredPackageLists_distro="$(getDistro)"
@@ -580,7 +579,7 @@ buildRequiredPackageLists () {
 #
 # Output:
 #   Space-separated list of every APT/APK packages that will be installed
-expandPackagesToBeInstalled () {
+expandPackagesToBeInstalled() {
 	expandPackagesToBeInstalled_result=''
 	case "$(getDistro)" in
 		alpine)
@@ -637,7 +636,7 @@ expandPackagesToBeInstalled () {
 #
 # Arguments:
 #   $@: the list of APT/APK packages to be installed
-installRequiredPackages () {
+installRequiredPackages() {
 	printf '### INSTALLING REQUIRED PACKAGES ###\n'
 	printf '# Packages to be kept after installation: %s\n' "$PACKAGES_PERSISTENT"
 	printf '# Packages to be used only for installation: %s\n' "$PACKAGES_VOLATILE"
@@ -667,7 +666,7 @@ installRequiredPackages () {
 getInstalledPackageVersion() {
 	case "$(getDistro)" in
 		alpine)
-			apk info "$1" | head -n1 | cut -c $(( ${#1} + 2 ))- | grep -o -E '^[0-9]+(\.[0-9]+){0,2}'
+			apk info "$1" | head -n1 | cut -c $((${#1} + 2))- | grep -o -E '^[0-9]+(\.[0-9]+){0,2}'
 			;;
 		debian)
 			dpkg-query --showformat='${Version}' --show "$1" 2>/dev/null | grep -o -E '^[0-9]+(\.[0-9]+){0,2}'
@@ -688,7 +687,7 @@ getInstalledPackageVersion() {
 compareVersions() {
 	compareVersions_v1="$1.0.0"
 	compareVersions_v2="$2.0.0"
-	compareVersions_vMin="$(printf '%s\n%s' "${compareVersions_v1}" "${compareVersions_v2}" | sort -t '.' -n -k1,1 -k2,2 -k3,3 | head -n 1)"
+	compareVersions_vMin="$(printf '%s\n%s' "$compareVersions_v1" "$compareVersions_v2" | sort -t '.' -n -k1,1 -k2,2 -k3,3 | head -n 1)"
 	if test "$compareVersions_vMin" != "$compareVersions_v1"; then
 		echo '1'
 	elif test "$compareVersions_vMin" = "$compareVersions_v2"; then
@@ -709,7 +708,7 @@ compareVersions() {
 #
 # Output:
 #   Nothing
-installBundledModule () {
+installBundledModule() {
 	printf '### INSTALLING BUNDLED MODULE %s ###\n' "$2"
 	case "$2" in
 		gd)
@@ -736,7 +735,7 @@ installBundledModule () {
 		imap)
 			PHP_OPENSSL=yes docker-php-ext-configure imap --with-kerberos --with-imap-ssl
 			;;
-		interbase|pdo_firebird)
+		interbase | pdo_firebird)
 			case "$(getDistro)" in
 				alpine)
 					if ! test -d /tmp/src/firebird; then
@@ -758,9 +757,9 @@ installBundledModule () {
 		ldap)
 			docker-php-ext-configure ldap --with-libdir=lib/$(gcc -dumpmachine)
 			;;
-		mssql|pdo_dblib)
+		mssql | pdo_dblib)
 			case "$1" in
-				506|700|701|702|703|704)
+				506 | 700 | 701 | 702 | 703 | 704)
 					if ! test -f /usr/lib/libsybdb.so; then
 						ln -s /usr/lib/x86_64-linux-gnu/libsybdb.so /usr/lib/libsybdb.so
 						UNNEEDED_PACKAGE_LINKS="$UNNEEDED_PACKAGE_LINKS /usr/lib/libsybdb.so"
@@ -770,7 +769,7 @@ installBundledModule () {
 			;;
 		odbc)
 			case "$1" in
-				506|700|701|702|703|704)
+				506 | 700 | 701 | 702 | 703 | 704)
 					docker-php-source extract
 					cd /usr/src/php/ext/odbc
 					phpize
@@ -821,7 +820,7 @@ installBundledModule () {
 #
 # Output:
 #   The path of the extracted directory
-getPackageSource () {
+getPackageSource() {
 	mkdir -p /tmp/src
 	getPackageSource_tempFile=$(mktemp -p /tmp/src)
 	curl -L -s -S -o "$getPackageSource_tempFile" "$1"
@@ -852,7 +851,7 @@ getPackageSource () {
 #   $2: the URL of the module source code
 #   $3: the options of the configure command
 #   $4: the value of CFLAGS
-installModuleFromSource () {
+installModuleFromSource() {
 	printf '### INSTALLING MODULE %s FROM SOURCE CODE ###\n' "$1"
 	installModuleFromSource_dir="$(getPackageSource "$2")"
 	cd "$installModuleFromSource_dir"
@@ -868,7 +867,7 @@ installModuleFromSource () {
 # Arguments:
 #   $1: the numeric PHP Major-Minor version
 #   $2: the handle of the PHP module
-installPECLModule () {
+installPECLModule() {
 	printf '### INSTALLING PECL MODULE %s ###\n' "$2"
 	installPECLModule_actual="$2"
 	installPECLModule_stdin='\n'
@@ -1054,7 +1053,7 @@ installPECLModule () {
 # Return:
 #   0 (true): if the string is in the list
 #   1 (false): if the string is not in the list
-stringInList () {
+stringInList() {
 	for stringInList_listItem in $2; do
 		if test "$1" = "$stringInList_listItem"; then
 			return 0
@@ -1071,7 +1070,7 @@ stringInList () {
 #
 # Output:
 #   The list without the word
-removeStringFromList () {
+removeStringFromList() {
 	removeStringFromList_result=''
 	for removeStringFromList_listItem in $2; do
 		if test "$1" != "$removeStringFromList_listItem"; then
@@ -1086,7 +1085,7 @@ removeStringFromList () {
 }
 
 # Cleanup everything at the end of the execution
-cleanup () {
+cleanup() {
 	cleanup_distro="$(getDistro)"
 	if test -n "$UNNEEDED_PACKAGE_LINKS"; then
 		printf '### REMOVING UNNEEDED PACKAGE LINKS ###\n'
@@ -1123,10 +1122,10 @@ cleanup () {
 resetIFS
 PHP_MAJMIN_VERSION=$(getPHPMajorMinor)
 case "$PHP_MAJMIN_VERSION" in
-	506|700|701|702|703|704)
-		;;
+	506 | 700 | 701 | 702 | 703 | 704) ;;
 	*)
-		printf "### ERROR: Unsupported PHP version: %s.%s ###\n" $(( PHP_MAJMIN_VERSION / 100 )) $(( PHP_MAJMIN_VERSION % 100 ))
+		printf "### ERROR: Unsupported PHP version: %s.%s ###\n" $((PHP_MAJMIN_VERSION / 100)) $((PHP_MAJMIN_VERSION % 100))
+		;;
 esac
 UNNEEDED_PACKAGE_LINKS=''
 processCommandArguments "$@"
diff --git a/scripts/common b/scripts/common
index 0914b89..11cb972 100755
--- a/scripts/common
+++ b/scripts/common
@@ -1,7 +1,7 @@
 #!/bin/sh
 
 # Reset the Internal Field Separator
-resetIFS () {
+resetIFS() {
 	IFS='	 
 '
 }
@@ -15,12 +15,10 @@ resetIFS () {
 # Return:
 # 0 (true): if the string is in the list
 # 1 (false): if the string is not in the list
-stringInList () {
+stringInList() {
 	resetIFS
-	for stringInList_listItem in ${2}
-	do
-		if test "${1}" = "${stringInList_listItem}"
-		then
+	for stringInList_listItem in $2; do
+		if test "$1" = "$stringInList_listItem"; then
 			return 0
 		fi
 	done
@@ -35,20 +33,17 @@ stringInList () {
 #
 # Output:
 # The space-separated list of strings that are present in both lists
-commonElements () {
+commonElements() {
 	commonElements_result=''
 	resetIFS
-	for commonElements_inA in ${1}
-	do
-		if stringInList "${commonElements_inA}" "${2}"
-		then
-			if test -z "${commonElements_result}"
-			then
-				commonElements_result="${commonElements_inA}"
+	for commonElements_inA in $1; do
+		if stringInList "$commonElements_inA" "$2"; then
+			if test -z "$commonElements_result"; then
+				commonElements_result="$commonElements_inA"
 			else
-				commonElements_result="${commonElements_result} ${commonElements_inA}"
+				commonElements_result="$commonElements_result $commonElements_inA"
 			fi
 		fi
 	done
-	echo "${commonElements_result}"
+	echo "$commonElements_result"
 }
diff --git a/scripts/travisci-test-extensions b/scripts/travisci-test-extensions
index 6ce770e..34d3eba 100755
--- a/scripts/travisci-test-extensions
+++ b/scripts/travisci-test-extensions
@@ -22,7 +22,7 @@ ALREADY_TESTED_EXTENSIONS=''
 #
 # Outputs:
 # the full docker image ID
-getDockerImageName () {
+getDockerImageName() {
 	case "$2" in
 		*)
 			getDockerImageName_version="$2"
@@ -43,8 +43,7 @@ getDockerImageName () {
 		alpine3.4)
 			# available for PHP from version 5.6 to version 7.1
 			case "$2" in
-				5.*|7.0|7.1)
-					;;
+				5.* | 7.0 | 7.1) ;;
 				*)
 					return
 					;;
@@ -53,8 +52,7 @@ getDockerImageName () {
 		alpine3.6)
 			# available for PHP 7.2
 			case "$2" in
-				7.2)
-					;;
+				7.2) ;;
 				*)
 					return
 					;;
@@ -67,8 +65,7 @@ getDockerImageName () {
 				7.0)
 					#getDockerImageName_distro='-alpine'
 					;;
-				5.*|7.1|7.2)
-					;;
+				5.* | 7.1 | 7.2) ;;
 				*)
 					return
 					;;
@@ -81,8 +78,7 @@ getDockerImageName () {
 				5.6)
 					#getDockerImageName_distro='-alpine'
 					;;
-				5.*|7.1|7.2|7.3)
-					;;
+				5.* | 7.1 | 7.2 | 7.3) ;;
 				*)
 					return
 					;;
@@ -91,8 +87,7 @@ getDockerImageName () {
 		alpine3.9)
 			# available for PHP from version 7.1 to version 7.3
 			case "$2" in
-				7.1|7.2|7.3)
-					;;
+				7.1 | 7.2 | 7.3) ;;
 				*)
 					return
 					;;
@@ -102,10 +97,10 @@ getDockerImageName () {
 			# available for PHP from version 7.1
 			# default Alpine one for PHP 7.1 -> 7.4
 			case "$2" in
-				7.1|7.2|7.3|7.4)
+				7.1 | 7.2 | 7.3 | 7.4)
 					#getDockerImageName_distro='-alpine'
 					;;
-				5.*|7.0)
+				5.* | 7.0)
 					return
 					;;
 			esac
@@ -113,8 +108,7 @@ getDockerImageName () {
 		jessie) # Debian 8
 			# available for PHP up to version 7.1
 			case "$2" in
-				5.*|7.0|7.1)
-					;;
+				5.* | 7.0 | 7.1) ;;
 				*)
 					return
 					;;
@@ -124,11 +118,10 @@ getDockerImageName () {
 			# available for PHP up to version 7.3
 			# default one for PHP 5.6 -> 7.0
 			case "$2" in
-				5.*|7.0)
+				5.* | 7.0)
 					#getDockerImageName_distro=''
 					;;
-				7.1|7.2|7.3)
-					;;
+				7.1 | 7.2 | 7.3) ;;
 				*)
 					return
 					;;
@@ -138,10 +131,10 @@ getDockerImageName () {
 			# available for PHP from version 7.1
 			# default one for PHP 7.1 -> 7.4
 			case "$2" in
-				7.1|7.2|7.3|7.4)
+				7.1 | 7.2 | 7.3 | 7.4)
 					#getDockerImageName_distro=''
 					;;
-				5.*|7.0)
+				5.* | 7.0)
 					return
 					;;
 			esac
@@ -154,7 +147,6 @@ getDockerImageName () {
 	printf 'php:%s%s%s' "$getDockerImageName_version" "$getDockerImageName_suffix" "$getDockerImageName_distro"
 }
 
-
 # Test an extension
 #
 # Arguments:
@@ -164,7 +156,7 @@ getDockerImageName () {
 # Return:
 # 0 (true): if test passes
 # 1 (false): if test fails
-testExtension () {
+testExtension() {
 	printf 'PHP version: %s\n' "$2"
 	if test -n "$(printf '%s' "$2" | sed -E 's/^[0-9]+\.[0-9]+$//')"; then
 		printf '  INVALID PHP VERSION: %s\n' "$2" >&2
@@ -176,7 +168,7 @@ testExtension () {
 		return 0
 	fi
 	printf ' - Docker image: %s\n' "$testExtension_Image"
-	testExtension_out=`mktemp`
+	testExtension_out="$(mktemp)"
 	if $(docker run --rm --volume "$TRAVIS_BUILD_DIR:/app" --workdir /app "$testExtension_Image" sh -c "./install-php-extensions $1 && php ./scripts/check-installed-extension.php $1" >"$testExtension_out" 2>&1); then
 		rm -rf "$testExtension_out"
 		printf ' - Passed\n'
@@ -188,7 +180,6 @@ testExtension () {
 	return 1
 }
 
-
 # Test a new extension line
 #
 # Arguments:
@@ -198,7 +189,7 @@ testExtension () {
 # Return:
 # 0 (true): if test passes
 # 1 (false): if test fails
-testNewExtensionLine () {
+testNewExtensionLine() {
 	testNewExtensionLine_rc=0
 	if test $# -lt 2; then
 		printf 'Missing PHP version list for the new extension %s\n' "${1:-}"
@@ -223,7 +214,6 @@ testNewExtensionLine () {
 	return $testNewExtensionLine_rc
 }
 
-
 # Get the list of all supported PHP versions
 #
 # Arguments:
@@ -231,7 +221,7 @@ testNewExtensionLine () {
 #
 # Outputs:
 # the space-separated list of supported PHP versions
-getAllPHPVersionsForExtensions () {
+getAllPHPVersionsForExtensions() {
 	getAllPHPVersionsForExtensions_result=''
 	IFS=' '
 	for getAllPHPVersionsForExtensions_extension in $1; do
@@ -261,7 +251,7 @@ getAllPHPVersionsForExtensions () {
 #
 # Outputs:
 # the space-separated list of supported PHP versions
-getAllPHPVersionsForExtension () {
+getAllPHPVersionsForExtension() {
 	getAllPHPVersionsForExtension_result=''
 	while IFS= read -r getAllPHPVersionsForExtension_line; do
 		getAllPHPVersionsForExtension_ok=
@@ -285,11 +275,10 @@ getAllPHPVersionsForExtension () {
 				fi
 			fi
 		done
-	done < "$TRAVIS_BUILD_DIR/data/supported-extensions"
+	done <"$TRAVIS_BUILD_DIR/data/supported-extensions"
 	printf '%s' "$getAllPHPVersionsForExtension_result"
 }
 
-
 # Test extensions by reading a commit message
 #
 # Arguments:
@@ -301,27 +290,26 @@ getAllPHPVersionsForExtension () {
 # Return:
 # 0 (true): if test passes
 # 1 (false): if test fails
-testExtensionsFromMessage () {
+testExtensionsFromMessage() {
 	testExtensionsFromMessage_result=0
 	TEST_EXTENSIONS=
 	FIRST_LINE=1
 	testExtensionsFromMessage_message="$(git -C "$TRAVIS_BUILD_DIR" log --pretty='format:%B' -n 1 "$1")"
 	IFS='
 '
-	
 	for COMMIT_LINE in $testExtensionsFromMessage_message; do
 		if test $FIRST_LINE -eq 1; then
 			FIRST_LINE=0
 		else
 			TESTLIST=
 			case "$COMMIT_LINE" in
-				Test:* )
+				Test:*)
 					TESTLIST=${COMMIT_LINE#Test:}
 					;;
-				TEST:* )
+				TEST:*)
 					TESTLIST=${COMMIT_LINE#TEST:}
 					;;
-				test:* )
+				test:*)
 					TESTLIST=${COMMIT_LINE#test:}
 					;;
 			esac
@@ -331,7 +319,7 @@ testExtensionsFromMessage () {
 					if test $COMMIT_LINE_EXT = '-STOP-'; then
 						STOP_NEXT_COMMITS=1
 					elif test -z "$TEST_EXTENSIONS"; then
-						TEST_EXTENSIONS=$COMMIT_LINE_EXT;
+						TEST_EXTENSIONS=$COMMIT_LINE_EXT
 					else
 						if ! stringInList "$COMMIT_LINE_EXT" "$TEST_EXTENSIONS"; then
 							TEST_EXTENSIONS="$TEST_EXTENSIONS $COMMIT_LINE_EXT"
@@ -380,7 +368,6 @@ for DIFF_LINE in $(git -C "$TRAVIS_BUILD_DIR" diff --no-indent-heuristic --minim
 	fi
 done
 
-
 IFS='
 '
 for COMMIT_HASH in $(git -C "$TRAVIS_BUILD_DIR" log --pretty='format:%H' "$TRAVIS_COMMIT_RANGE"); do
diff --git a/scripts/travisci-update-readme b/scripts/travisci-update-readme
index 86bd340..7af4b2e 100755
--- a/scripts/travisci-update-readme
+++ b/scripts/travisci-update-readme
@@ -9,19 +9,15 @@ UPDATE_README_COMMIT_AUTHOR_EMAIL='michele@locati.it'
 UPDATE_README_COMMIT_MESSAGE='[skip ci] Automatically update README.md'
 WATCHED_FILES='data/special-requirements data/supported-extensions scripts/common scripts/update-readme scripts/travisci-update-readme'
 
-SCRIPTS_DIR="$(CDPATH= cd -- "$(dirname -- "${0}")" && pwd)"
-. "${SCRIPTS_DIR}/common"
-
+SCRIPTS_DIR="$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)"
+. "$SCRIPTS_DIR/common"
 
 echo 'Checking environment'
-if test -z "${TRAVIS_BUILD_DIR:-}" || test -z "${TRAVIS_BRANCH:-}" || test -z "${TRAVIS_EVENT_TYPE:-}" || test -z "${TRAVIS_REPO_SLUG:-}"
-then
+if test -z "${TRAVIS_BUILD_DIR:-}" || test -z "${TRAVIS_BRANCH:-}" || test -z "${TRAVIS_EVENT_TYPE:-}" || test -z "${TRAVIS_REPO_SLUG:-}"; then
 	echo 'Not in a TravisCI environment' >&2
 	exit 1
 fi
-if test -z "${GUTHUB_ACCESS_TOKEN:-}"
-then
-	
+if test -z "${GUTHUB_ACCESS_TOKEN:-}"; then
 	echo 'GitHub access token not set' >&2
 	# To create it:
 	#  - go to https://github.com/settings/tokens/new?scopes=repo
@@ -35,47 +31,43 @@ then
 	#        - secure: "encrypted string"
 	exit 1
 fi
-if test "${TRAVIS_EVENT_TYPE}" != 'push'
-then
+if test "$TRAVIS_EVENT_TYPE" != 'push'; then
 	echo 'This script should only be run in push builds' >&2
 	exit 1
 fi
 
-printf 'Checking-out branch %s\n' "${TRAVIS_BRANCH}"
-git checkout --force "${TRAVIS_BRANCH}"
+printf 'Checking-out branch %s\n' "$TRAVIS_BRANCH"
+git checkout --force "$TRAVIS_BRANCH"
 
-LAST_AUTO_UPDATED_IN="$(git -C "${TRAVIS_BUILD_DIR}" rev-list --max-count 1 --author "<${UPDATE_README_COMMIT_AUTHOR_EMAIL}>" --grep "${UPDATE_README_COMMIT_MESSAGE}" "${TRAVIS_BRANCH}")"
-if test -z "${LAST_AUTO_UPDATED_IN}"
-then
-	printf 'Rebuild of README.md enabled (no previous automatic refresh of it in branch %s)\n' "${TRAVIS_BRANCH}"
+LAST_AUTO_UPDATED_IN="$(git -C "$TRAVIS_BUILD_DIR" rev-list --max-count 1 --author "<$UPDATE_README_COMMIT_AUTHOR_EMAIL>" --grep "$UPDATE_README_COMMIT_MESSAGE" "$TRAVIS_BRANCH")"
+if test -z "$LAST_AUTO_UPDATED_IN"; then
+	printf 'Rebuild of README.md enabled (no previous automatic refresh of it in branch %s)\n' "$TRAVIS_BRANCH"
 else
-	MODIFIED_FILES_SINCE="$(git -C "${TRAVIS_BUILD_DIR}" diff --name-only "${LAST_AUTO_UPDATED_IN}...${TRAVIS_BRANCH}")"
-	if test -z "$(commonElements "${WATCHED_FILES}" "${MODIFIED_FILES_SINCE}")"
-	then
-		printf 'Rebuild of README.md not needed (no relevant files changed in branch %s since commit %s)\n' "${TRAVIS_BRANCH}" "${LAST_AUTO_UPDATED_IN}"
+	MODIFIED_FILES_SINCE="$(git -C "$TRAVIS_BUILD_DIR" diff --name-only "$LAST_AUTO_UPDATED_IN...$TRAVIS_BRANCH")"
+	if test -z "$(commonElements "$WATCHED_FILES" "$MODIFIED_FILES_SINCE")"; then
+		printf 'Rebuild of README.md not needed (no relevant files changed in branch %s since commit %s)\n' "$TRAVIS_BRANCH" "$LAST_AUTO_UPDATED_IN"
 		exit 0
 	fi
-	printf 'Rebuild of README.md enabled (relevant files changed in branch %s since commit %s)\n' "${TRAVIS_BRANCH}" "${LAST_AUTO_UPDATED_IN}"
+	printf 'Rebuild of README.md enabled (relevant files changed in branch %s since commit %s)\n' "$TRAVIS_BRANCH" "$LAST_AUTO_UPDATED_IN"
 fi
 
 echo 'Updating README.md'
-"${TRAVIS_BUILD_DIR}/scripts/update-readme"
-if test -z "$(git -C "${TRAVIS_BUILD_DIR}" ls-files -m | grep -E '^README\.md$')"
-then
+"$TRAVIS_BUILD_DIR/scripts/update-readme"
+if test -z "$(git -C "$TRAVIS_BUILD_DIR" ls-files -m | grep -E '^README\.md$')"; then
 	echo 'README.md has not been changed'
 	exit 0
 fi
 
-printf 'Adding %s remote\n' "${TRAVIS_REPO_SLUG}"
-git remote add deploy "https://${GUTHUB_ACCESS_TOKEN}@github.com/${TRAVIS_REPO_SLUG}.git"
+printf 'Adding %s remote\n' "$TRAVIS_REPO_SLUG"
+git remote add deploy "https://$GUTHUB_ACCESS_TOKEN@github.com/$TRAVIS_REPO_SLUG.git"
 
 echo 'Committing changes to README.md'
-git -C "${TRAVIS_BUILD_DIR}" config user.name "${UPDATE_README_COMMIT_AUTHOR_NAME}"
-git -C "${TRAVIS_BUILD_DIR}" config user.email "${UPDATE_README_COMMIT_AUTHOR_EMAIL}"
-git -C "${TRAVIS_BUILD_DIR}" add README.md
-git -C "${TRAVIS_BUILD_DIR}" commit -m "${UPDATE_README_COMMIT_MESSAGE}"
+git -C "$TRAVIS_BUILD_DIR" config user.name "$UPDATE_README_COMMIT_AUTHOR_NAME"
+git -C "$TRAVIS_BUILD_DIR" config user.email "$UPDATE_README_COMMIT_AUTHOR_EMAIL"
+git -C "$TRAVIS_BUILD_DIR" add README.md
+git -C "$TRAVIS_BUILD_DIR" commit -m "$UPDATE_README_COMMIT_MESSAGE"
 
-printf 'Pushing to %s\n' "${TRAVIS_REPO_SLUG}"
-git push deploy "${TRAVIS_BRANCH}"
+printf 'Pushing to %s\n' "$TRAVIS_REPO_SLUG"
+git push deploy "$TRAVIS_BRANCH"
 
 echo 'Done.'
diff --git a/scripts/update-readme b/scripts/update-readme
index b5f7df3..3eff6ad 100755
--- a/scripts/update-readme
+++ b/scripts/update-readme
@@ -3,12 +3,11 @@
 set -o errexit
 set -o nounset
 
-SCRIPTS_DIR="$(CDPATH= cd -- "$(dirname -- "${0}")" && pwd)"
-ROOT_DIR="$(dirname -- "${SCRIPTS_DIR}")"
-DATA_DIR="${ROOT_DIR}/data"
-
-. "${SCRIPTS_DIR}/common"
+SCRIPTS_DIR="$(CDPATH= cd -- "$(dirname -- "$0")" && pwd)"
+ROOT_DIR="$(dirname -- "$SCRIPTS_DIR")"
+DATA_DIR="$ROOT_DIR/data"
 
+. "$SCRIPTS_DIR/common"
 
 # Get the list of PHP extensions from the data file
 #
@@ -17,26 +16,25 @@ DATA_DIR="${ROOT_DIR}/data"
 #
 # Output:
 # the list of PHP extensions
-getExtensionList () {
+getExtensionList() {
 	getExtensionList_extensions=''
 	IFS='
 '
-	for getExtensionList_line in $(cat -- "${1}" | sort); do
+	for getExtensionList_line in $(cat -- "$1" | sort); do
 		getExtensionList_extension=''
 		IFS=' 	'
-		for getExtensionList_chunk in ${getExtensionList_line}; do
-			if test -z "${getExtensionList_extensions}"; then
-				getExtensionList_extensions="${getExtensionList_chunk}"
+		for getExtensionList_chunk in $getExtensionList_line; do
+			if test -z "$getExtensionList_extensions"; then
+				getExtensionList_extensions="$getExtensionList_chunk"
 			else
-				getExtensionList_extensions="${getExtensionList_extensions} ${getExtensionList_chunk}"
+				getExtensionList_extensions="$getExtensionList_extensions $getExtensionList_chunk"
 			fi
 			break
 		done
 	done
-	printf '%s' "${getExtensionList_extensions}"
+	printf '%s' "$getExtensionList_extensions"
 }
 
-
 # Get the list of PHP versions from the data file
 #
 # Arguments:
@@ -44,27 +42,26 @@ getExtensionList () {
 #
 # Output:
 # the list of PHP versions
-getVersionList () {
+getVersionList() {
 	getVersionList_versions=''
 	IFS='
 '
-	for getVersionList_line in $(cat -- "${1}" | sort); do
+	for getVersionList_line in $(cat -- "$1" | sort); do
 		getVersionList_extension=''
 		IFS=' 	'
-		for getVersionList_chunk in ${getVersionList_line}; do
-			if test -z "${getVersionList_extension}"; then
-				getVersionList_extension="${getVersionList_chunk}"
-			elif test -z "${getVersionList_versions}"; then
-				getVersionList_versions="${getVersionList_chunk}"
-			elif ! stringInList "${getVersionList_chunk}" "${getVersionList_versions}"; then
-				getVersionList_versions="${getVersionList_versions} ${getVersionList_chunk}"
+		for getVersionList_chunk in $getVersionList_line; do
+			if test -z "$getVersionList_extension"; then
+				getVersionList_extension="$getVersionList_chunk"
+			elif test -z "$getVersionList_versions"; then
+				getVersionList_versions="$getVersionList_chunk"
+			elif ! stringInList "$getVersionList_chunk" "$getVersionList_versions"; then
+				getVersionList_versions="$getVersionList_versions $getVersionList_chunk"
 			fi
 		done
 	done
-	sortVersionList "${getVersionList_versions}"
+	sortVersionList "$getVersionList_versions"
 }
 
-
 # Sort the list of PHP versions
 #
 # Arguments:
@@ -72,21 +69,20 @@ getVersionList () {
 #
 # Output:
 # the sorted list of PHP versions
-sortVersionList () {
+sortVersionList() {
 	sortVersionList_list=''
 	IFS='
 '
-	for sortVersionList_version in $(printf '%s' "${1}" | tr ' ' '\n' | sort -t '.' -k 1,1n -k 2,2n -k 3,3n); do
-		if test -z "${sortVersionList_list}"; then
-			sortVersionList_list="${sortVersionList_version}"
+	for sortVersionList_version in $(printf '%s' "$1" | tr ' ' '\n' | sort -t '.' -k 1,1n -k 2,2n -k 3,3n); do
+		if test -z "$sortVersionList_list"; then
+			sortVersionList_list="$sortVersionList_version"
 		else
-			sortVersionList_list="${sortVersionList_list} ${sortVersionList_version}"
+			sortVersionList_list="$sortVersionList_list $sortVersionList_version"
 		fi
 	done
-	printf '%s' "${sortVersionList_list}"
+	printf '%s' "$sortVersionList_list"
 }
 
-
 # Generate the markdown table with the supported PHP extensions
 #
 # Arguments:
@@ -94,41 +90,41 @@ sortVersionList () {
 #
 # Output:
 # the markdown table
-generateExtensionsTable () {
-	generateExtensionsTable_data=$(cat "${1}")
-	generateExtensionsTable_extensions="$(getExtensionList "${1}")"
-	generateExtensionsTable_versions="$(getVersionList "${1}")"
+generateExtensionsTable() {
+	generateExtensionsTable_data=$(cat "$1")
+	generateExtensionsTable_extensions="$(getExtensionList "$1")"
+	generateExtensionsTable_versions="$(getVersionList "$1")"
 	generateExtensionsTable_count=0
 	printf '| Extension |'
 	IFS=' '
-	for generateExtensionsTable_version in ${generateExtensionsTable_versions}; do
-		printf ' PHP %s |' "${generateExtensionsTable_version}"
+	for generateExtensionsTable_version in $generateExtensionsTable_versions; do
+		printf ' PHP %s |' "$generateExtensionsTable_version"
 	done
 	printf '\n'
 	printf '|:---:|'
-	for generateExtensionsTable_version in ${generateExtensionsTable_versions}; do
+	for generateExtensionsTable_version in $generateExtensionsTable_versions; do
 		printf -- ':---:|'
 	done
 	printf '\n'
 	IFS=' '
-	for generateExtensionsTable_extension in ${generateExtensionsTable_extensions}; do
+	for generateExtensionsTable_extension in $generateExtensionsTable_extensions; do
 		generateExtensionsTable_count=$((generateExtensionsTable_count + 1))
-		printf '| %s |' "${generateExtensionsTable_extension}"
+		printf '| %s |' "$generateExtensionsTable_extension"
 		IFS=' '
-		for generateExtensionsTable_version in ${generateExtensionsTable_versions}; do
+		for generateExtensionsTable_version in $generateExtensionsTable_versions; do
 			printf ' '
 			generateExtensionsTable_versionOk=''
 			IFS='
 '
-			for generateExtensionsTable_dataLine in ${generateExtensionsTable_data}; do
-				if stringInList "${generateExtensionsTable_extension}" "${generateExtensionsTable_dataLine}"; then
-					if stringInList "${generateExtensionsTable_version}" "${generateExtensionsTable_dataLine}"; then
+			for generateExtensionsTable_dataLine in $generateExtensionsTable_data; do
+				if stringInList "$generateExtensionsTable_extension" "$generateExtensionsTable_dataLine"; then
+					if stringInList "$generateExtensionsTable_version" "$generateExtensionsTable_dataLine"; then
 						generateExtensionsTable_versionOk='y'
 					fi
 					break
 				fi
 			done
-			if test -n "${generateExtensionsTable_versionOk}"; then
+			if test -n "$generateExtensionsTable_versionOk"; then
 				printf 'V'
 			fi
 			printf ' |'
@@ -139,7 +135,6 @@ generateExtensionsTable () {
 	printf '*Number of supported extensions: %s*\n' $generateExtensionsTable_count
 }
 
-
 # Generate the markdown table with the special requirements for the PHP extensions
 #
 # Arguments:
@@ -147,30 +142,29 @@ generateExtensionsTable () {
 #
 # Output:
 # the markdown table
-generateSpecialRequirementsTable () {
+generateSpecialRequirementsTable() {
 	generateSpecialRequirementsTable_started=''
 	IFS='
 '
-	for generateSpecialRequirementsTable_line in $(cat -- "${1}" | sort); do
-		if test -z "${generateSpecialRequirementsTable_started}"; then
+	for generateSpecialRequirementsTable_line in $(cat -- "$1" | sort); do
+		if test -z "$generateSpecialRequirementsTable_started"; then
 			printf '| Extension | Requirements |\n'
 			printf '|:---:|:---:|\n'
 			generateSpecialRequirementsTable_started='y'
 		fi
 		resetIFS
-		generateSpecialRequirementsTable_requirement="$(echo "${generateSpecialRequirementsTable_line}" | sed -E 's/^\s*\w+\s+//')"
-		case "${generateSpecialRequirementsTable_requirement}" in
+		generateSpecialRequirementsTable_requirement="$(echo "$generateSpecialRequirementsTable_line" | sed -E 's/^\s*\w+\s+//')"
+		case "$generateSpecialRequirementsTable_requirement" in
 			zts)
 				generateSpecialRequirementsTable_requirement='Requires images with PHP compiled with thread-safety enabled (`zts`).'
 				;;
 		esac
 		printf '| %s | %s |\n' \
-			"$(echo "${generateSpecialRequirementsTable_line}" | awk '{print $1;}')" \
-			"${generateSpecialRequirementsTable_requirement}"
+			"$(echo "$generateSpecialRequirementsTable_line" | awk '{print $1;}')" \
+			"$generateSpecialRequirementsTable_requirement"
 	done
 }
 
-
 # Generate the contents of README.md
 #
 # Arguments:
@@ -180,20 +174,20 @@ generateSpecialRequirementsTable () {
 #
 # Output:
 # the markdown table
-generateReadme () {
+generateReadme() {
 	generateReadme_ph_ExtensionsStart='<!-- START OF EXTENSIONS TABLE -->'
 	generateReadme_ph_ExtensionsEnd='<!-- END OF EXTENSIONS TABLE -->'
 	generateReadme_ph_SpecialStart='<!-- START OF SPECIAL REQUIREMENTS -->'
 	generateReadme_ph_SpecialEnd='<!-- END OF SPECIAL REQUIREMENTS -->'
 	generateReadme_skip=''
 	while IFS= read -r generateReadme_line; do
-		if test "${generateReadme_line}" = "${generateReadme_ph_ExtensionsEnd}" || test "${generateReadme_line}" = "${generateReadme_ph_SpecialEnd}"; then
+		if test "$generateReadme_line" = "$generateReadme_ph_ExtensionsEnd" || test "$generateReadme_line" = "$generateReadme_ph_SpecialEnd"; then
 			generateReadme_skip=''
 		fi
-		if test -z "${generateReadme_skip}"; then
-			printf '%s\n' "${generateReadme_line}"
+		if test -z "$generateReadme_skip"; then
+			printf '%s\n' "$generateReadme_line"
 		fi
-		if test "${generateReadme_line}" = "${generateReadme_ph_ExtensionsStart}"; then
+		if test "$generateReadme_line" = "$generateReadme_ph_ExtensionsStart"; then
 			generateReadme_skip='y'
 			printf '<!-- ########################################################### -->\n'
 			printf '<!-- #                                                         # -->\n'
@@ -202,8 +196,8 @@ generateReadme () {
 			printf '<!-- #  EDIT THE data/supported-extensions FILE INSTEAD        # -->\n'
 			printf '<!-- #                                                         # -->\n'
 			printf '<!-- ########################################################### -->\n'
-			generateExtensionsTable "${2}"
-		elif test "${generateReadme_line}" = "${generateReadme_ph_SpecialStart}"; then
+			generateExtensionsTable "$2"
+		elif test "$generateReadme_line" = "$generateReadme_ph_SpecialStart"; then
 			generateReadme_skip='y'
 			printf '<!-- ########################################################### -->\n'
 			printf '<!-- #                                                         # -->\n'
@@ -212,11 +206,11 @@ generateReadme () {
 			printf '<!-- #  EDIT THE data/special-requirements FILE INSTEAD        # -->\n'
 			printf '<!-- #                                                         # -->\n'
 			printf '<!-- ########################################################### -->\n'
-			generateSpecialRequirementsTable "${3}"
+			generateSpecialRequirementsTable "$3"
 		fi
-	done < "${1}"
-	printf '%s' "${generateReadme_line}"
+	done <"$1"
+	printf '%s' "$generateReadme_line"
 }
 
-NEW_README="$(generateReadme "${ROOT_DIR}/README.md" "${DATA_DIR}/supported-extensions" "${DATA_DIR}/special-requirements")"
-printf '%s\n' "${NEW_README}" > "${ROOT_DIR}/README.md"
+NEW_README="$(generateReadme "$ROOT_DIR/README.md" "$DATA_DIR/supported-extensions" "$DATA_DIR/special-requirements")"
+printf '%s\n' "$NEW_README" >"$ROOT_DIR/README.md"