diff --git a/.github/workflows/force.yml b/.github/workflows/force.yml
new file mode 100644
index 0000000..0ed3817
--- /dev/null
+++ b/.github/workflows/force.yml
@@ -0,0 +1,75 @@
+name: build by force
+
+on:
+#   push:
+#     branches:
+#       - master
+#       - main
+  workflow_dispatch:
+#   repository_dispatch:
+#     types: php
+
+jobs:
+  php:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: checkout code
+        uses: actions/checkout@v2
+      - name: docker login
+        run: docker login -u ${{ secrets.DOCKERUSERNAME }} -p ${{ secrets.DOCKERAPIKEY }}
+      - name: treehouses php
+        run: |
+          export DOCKER_CLI_EXPERIMENTAL=enabled
+          repo="treehouses/php"
+          base="treehouses/alpine"
+          source .github/workflows/utils.sh
+          echo "amd64"
+          baseamd64=$(get_variant_sha "$base" "latest" "amd64")
+          echo $baseamd64
+          # repoamd64=$(get_manifest_sha "$repo:latest" "amd64")
+          # echo $repoamd64
+          echo "arm"
+          basearm=$(get_tag_sha "$base" "latest")
+          echo $basearm
+          # repoarm=$(get_manifest_sha "$repo:latest" "arm")
+          # echo $repoarm
+          echo "arm64"
+          basearm64=$(get_variant_sha "$base" "latest" "arm64")
+          echo $basearm64
+          # repoarm64=$(get_manifest_sha "$repo:latest" "arm64")
+          # echo $repoarm64
+          echo "change"
+          flag=true #$(compare_sha "$baseamd64" "$repoamd64" "$basearm" "$repoarm" "$basearm64" "$repoarm64")
+          echo $flag
+          if [[ $flag == true ]]; then
+            docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+            build_image "$base:latest" amd64 $repo
+            build_image "$base:latest" arm $repo
+            build_image "$base:latest" arm64 $repo
+            deploy_image $repo arm
+            deploy_image $repo amd64
+            deploy_image $repo arm64
+            sudo npm install -g @treehouses/cli
+            export gitter_channel="${{ secrets.CHANNEL }}"
+            echo "tags"
+            tag="$(date +%Y%m%d%H%M)"
+            echo $tag
+            docker manifest create $repo:$tag $repo-tags:amd64 $repo-tags:arm $repo-tags:arm64
+            docker manifest annotate $repo:$tag $repo-tags:amd64 --arch amd64
+            docker manifest annotate $repo:$tag $repo-tags:arm64 --arch arm64
+            docker manifest annotate $repo:$tag $repo-tags:arm --arch arm
+            docker manifest inspect $repo:$tag
+            docker manifest push $repo:$tag
+            tag2="latest"
+            echo $tag2
+            docker manifest create $repo:$tag2 $repo-tags:amd64 $repo-tags:arm $repo-tags:arm64
+            docker manifest annotate $repo:$tag2 $repo-tags:amd64 --arch amd64
+            docker manifest annotate $repo:$tag2 $repo-tags:arm64 --arch arm64
+            docker manifest annotate $repo:$tag2 $repo-tags:arm --arch arm
+            docker manifest inspect $repo:$tag2
+            docker manifest push $repo:$tag2
+            echo "https://hub.docker.com/r/treehouses/php/tags"
+            treehouses feedback "new treehouses/php check https://hub.docker.com/r/treehouses/php/tags"
+          else
+            echo "no changes"
+          fi
diff --git a/.github/workflows/php.yml b/.github/workflows/php.yml
new file mode 100644
index 0000000..c9ac089
--- /dev/null
+++ b/.github/workflows/php.yml
@@ -0,0 +1,75 @@
+name: build on change
+
+on:
+  push:
+    branches:
+      - master
+      - main
+  workflow_dispatch:
+  repository_dispatch:
+    types: php
+
+jobs:
+  php:
+    runs-on: ubuntu-20.04
+    steps:
+      - name: checkout code
+        uses: actions/checkout@v2
+      - name: docker login
+        run: docker login -u ${{ secrets.DOCKERUSERNAME }} -p ${{ secrets.DOCKERAPIKEY }}
+      - name: treehouses php
+        run: |
+          export DOCKER_CLI_EXPERIMENTAL=enabled
+          repo="treehouses/php"
+          base="treehouses/alpine"
+          source .github/workflows/utils.sh
+          echo "amd64"
+          baseamd64=$(get_variant_sha "$base" "latest" "amd64")
+          echo $baseamd64
+          repoamd64=$(get_manifest_sha "$repo:latest" "amd64")
+          echo $repoamd64
+          echo "arm"
+          basearm=$(get_tag_sha "$base" "latest")
+          echo $basearm
+          repoarm=$(get_manifest_sha "$repo:latest" "arm")
+          echo $repoarm
+          echo "arm64"
+          basearm64=$(get_variant_sha "$base" "latest" "arm64")
+          echo $basearm64
+          repoarm64=$(get_manifest_sha "$repo:latest" "arm64")
+          echo $repoarm64
+          echo "change"
+          flag=$(compare_sha "$baseamd64" "$repoamd64" "$basearm" "$repoarm" "$basearm64" "$repoarm64")
+          echo $flag
+          if [[ $flag == true ]]; then
+            docker run --rm --privileged multiarch/qemu-user-static --reset -p yes
+            build_image "$base:latest" amd64 $repo
+            build_image "$base:latest" arm $repo
+            build_image "$base:latest" arm64 $repo
+            deploy_image $repo arm
+            deploy_image $repo amd64
+            deploy_image $repo arm64
+            sudo npm install -g @treehouses/cli
+            export gitter_channel="${{ secrets.CHANNEL }}"
+            echo "tags"
+            tag="$(date +%Y%m%d%H%M)"
+            echo $tag
+            docker manifest create $repo:$tag $repo-tags:amd64 $repo-tags:arm $repo-tags:arm64
+            docker manifest annotate $repo:$tag $repo-tags:amd64 --arch amd64
+            docker manifest annotate $repo:$tag $repo-tags:arm64 --arch arm64
+            docker manifest annotate $repo:$tag $repo-tags:arm --arch arm
+            docker manifest inspect $repo:$tag
+            docker manifest push $repo:$tag
+            tag2="latest"
+            echo $tag2
+            docker manifest create $repo:$tag2 $repo-tags:amd64 $repo-tags:arm $repo-tags:arm64
+            docker manifest annotate $repo:$tag2 $repo-tags:amd64 --arch amd64
+            docker manifest annotate $repo:$tag2 $repo-tags:arm64 --arch arm64
+            docker manifest annotate $repo:$tag2 $repo-tags:arm --arch arm
+            docker manifest inspect $repo:$tag2
+            docker manifest push $repo:$tag2
+            echo "https://hub.docker.com/r/treehouses/php/tags"
+            treehouses feedback "new treehouses/php check https://hub.docker.com/r/treehouses/php/tags"
+          else
+            echo "no changes"
+          fi
diff --git a/.github/workflows/utils.sh b/.github/workflows/utils.sh
new file mode 100644
index 0000000..eef5302
--- /dev/null
+++ b/.github/workflows/utils.sh
@@ -0,0 +1,112 @@
+#!/bin/bash
+
+get_variant_sha(){
+    local sha
+    docker_repo=$1  #alpine or vmnet/alpine
+    manifest_tag=$2
+    docker_image=$docker_repo:$manifest_tag
+    arch=$3
+    variant=$4
+    export DOCKER_CLI_EXPERIMENTAL=enabled
+
+    docker pull -q  ${docker_image} &>/dev/null
+    docker manifest inspect ${docker_image} > "$2".txt
+
+    sha=""
+    i=0
+    while [ "$sha" == "" ] && read -r line
+    do
+        arch=$(jq .manifests[$i].platform.architecture "$2".txt |sed -e 's/^"//' -e 's/"$//')
+        if [ "$arch" = "$3" ] && [ "$arch" !=  "arm" ]; then
+            sha=$(jq .manifests[$i].digest "$2".txt  |sed -e 's/^"//' -e 's/"$//')
+            echo ${sha}
+        elif [ "$arch" = "$3" ]; then
+            variant=$(jq .manifests[$i].platform.variant "$2".txt |sed -e 's/^"//' -e 's/"$//')
+            if [ "$variant" == "$4" ]; then
+                sha=$(jq .manifests[$i].digest "$2".txt  |sed -e 's/^"//' -e 's/"$//')
+                echo ${sha}
+            fi
+        fi
+        i=$i+1
+    done < "$2".txt
+}
+
+get_manifest_sha (){
+    local repo=$1
+    local arch=$2
+    docker pull -q $1 &>/dev/null
+    docker manifest inspect $1 > "$2".txt
+    sha=""
+    i=0
+    while [ "$sha" == "" ] && read -r line
+    do
+        archecture=$(jq .manifests[$i].platform.architecture "$2".txt |sed -e 's/^"//' -e 's/"$//')
+        if [ "$archecture" = "$2" ];then
+            sha=$(jq .manifests[$i].digest "$2".txt  |sed -e 's/^"//' -e 's/"$//')
+            echo ${sha}
+        fi
+        i=$i+1
+    done < "$2".txt
+}
+
+get_tag_sha(){
+    local repo=$1
+    local tag=$2
+    docker pull "$repo:$tag" &>/dev/null
+    sha=$(docker inspect --format='{{index .RepoDigests 0}}' "$repo:$tag" 2>/dev/null | cut -d @ -f 2)
+    echo $sha
+}
+
+build_image(){
+  local repo=$1  # this is the base repo, for example treehouses/alpine
+  local arch=$2  #arm arm64 amd64
+  local tag_repo=$3  # this is the tag repo, for example treehouses/node
+  if [ $# -le 1 ]; then
+    echo "missing parameters."
+    exit 1
+  fi
+  sha=$(get_manifest_sha $@)
+  echo $sha
+  base_image="$repo@$sha"
+  echo $base_image
+  if [ -n "$sha" ]; then
+    tag=$tag_repo-tags:$arch
+    sed "s|{{base_image}}|$base_image|g" Dockerfile.template > Dockerfile.$arch
+    docker buildx build --platform linux/$arch -t $tag -f Dockerfile.$arch .
+  fi
+}
+
+deploy_image(){
+  local repo=$1
+  local arch=$2  #arm arm64 amd64
+  tag_arch=$repo-tags:$arch
+  tag_time=$(date +%Y%m%d%H%M)
+  tag_arch_time=$repo-tags:$arch-$tag_time
+  echo $tag_arch_time
+  docker tag $tag_arch $tag_arch_time
+  docker push $tag_arch_time
+  docker tag $tag_arch_time $tag_arch
+  docker push $tag_arch
+}
+
+compare_sha () {
+    if [ "$1" != "$2" ] || [ "$3" != "$4" ] || [ "$5" != "$6" ]; then
+        echo "true"
+    else
+        echo "false"
+    fi
+}
+
+create_manifests(){
+    local repo=$1
+    local tag=$2
+    local x86=$3
+    local rpi=$4
+    local arm64=$5
+    docker manifest create $repo:$tag $x86 $rpi $arm64
+    docker manifest create $repo:latest $x86 $rpi $arm64
+    docker manifest annotate $repo:latest $rpi --arch arm
+    docker manifest annotate $repo:$tag $arm64 --arch arm64
+    docker manifest annotate $repo:latest $arm64 --arch arm64
+    docker manifest annotate $repo:$tag $rpi --arch arm
+}
diff --git a/Dockerfile.template b/Dockerfile.template
new file mode 100644
index 0000000..4d80bd1
--- /dev/null
+++ b/Dockerfile.template
@@ -0,0 +1,186 @@
+FROM {{base_image}}
+
+# dependencies required for running "phpize"
+# these get automatically installed and removed by "docker-php-ext-*" (unless they're already installed)
+ENV PHPIZE_DEPS \
+		autoconf \
+		dpkg-dev dpkg \
+		file \
+		g++ \
+		gcc \
+		libc-dev \
+		make \
+		pkgconf \
+		re2c
+
+# persistent / runtime deps
+RUN apk add --no-cache \
+		ca-certificates \
+		curl \
+		tar \
+		xz \
+# https://github.com/docker-library/php/issues/494
+		openssl
+
+# ensure www-data user exists
+RUN set -eux; \
+	addgroup -g 82 -S www-data; \
+	adduser -u 82 -D -S -G www-data www-data
+# 82 is the standard uid/gid for "www-data" in Alpine
+# https://git.alpinelinux.org/aports/tree/main/apache2/apache2.pre-install?h=3.14-stable
+# https://git.alpinelinux.org/aports/tree/main/lighttpd/lighttpd.pre-install?h=3.14-stable
+# https://git.alpinelinux.org/aports/tree/main/nginx/nginx.pre-install?h=3.14-stable
+
+ENV PHP_INI_DIR /usr/local/etc/php
+RUN set -eux; \
+	mkdir -p "$PHP_INI_DIR/conf.d"; \
+# allow running as an arbitrary user (https://github.com/docker-library/php/issues/743)
+	[ ! -d /var/www/html ]; \
+	mkdir -p /var/www/html; \
+	chown www-data:www-data /var/www/html; \
+	chmod 777 /var/www/html
+
+# Apply stack smash protection to functions using local buffers and alloca()
+# Make PHP's main executable position-independent (improves ASLR security mechanism, and has no performance impact on x86_64)
+# Enable optimization (-O2)
+# Enable linker optimization (this sorts the hash buckets to improve cache locality, and is non-default)
+# https://github.com/docker-library/php/issues/272
+# -D_LARGEFILE_SOURCE and -D_FILE_OFFSET_BITS=64 (https://www.php.net/manual/en/intro.filesystem.php)
+ENV PHP_CFLAGS="-fstack-protector-strong -fpic -fpie -O2 -D_LARGEFILE_SOURCE -D_FILE_OFFSET_BITS=64"
+ENV PHP_CPPFLAGS="$PHP_CFLAGS"
+ENV PHP_LDFLAGS="-Wl,-O1 -pie"
+
+ENV GPG_KEYS 42670A7FE4D0441C8E4632349E4FDC074A4EF02D 5A52880781F755608BF815FC910DEB46F53EA312
+
+ENV PHP_VERSION 7.4.21
+ENV PHP_URL="https://www.php.net/distributions/php-7.4.21.tar.xz" PHP_ASC_URL="https://www.php.net/distributions/php-7.4.21.tar.xz.asc"
+ENV PHP_SHA256="cf43384a7806241bc2ff22022619baa4abb9710f12ec1656d0173de992e32a90"
+
+RUN set -eux; \
+	\
+	apk add --no-cache --virtual .fetch-deps gnupg; \
+	\
+	mkdir -p /usr/src; \
+	cd /usr/src; \
+	\
+	curl -fsSL -o php.tar.xz "$PHP_URL"; \
+	\
+	if [ -n "$PHP_SHA256" ]; then \
+		echo "$PHP_SHA256 *php.tar.xz" | sha256sum -c -; \
+	fi; \
+	\
+	if [ -n "$PHP_ASC_URL" ]; then \
+		curl -fsSL -o php.tar.xz.asc "$PHP_ASC_URL"; \
+		export GNUPGHOME="$(mktemp -d)"; \
+		for key in $GPG_KEYS; do \
+			gpg --batch --keyserver keyserver.ubuntu.com --recv-keys "$key"; \
+		done; \
+		gpg --batch --verify php.tar.xz.asc php.tar.xz; \
+		gpgconf --kill all; \
+		rm -rf "$GNUPGHOME"; \
+	fi; \
+	\
+	apk del --no-network .fetch-deps
+
+COPY docker-php-source /usr/local/bin/
+
+RUN set -eux; \
+	apk add --no-cache --virtual .build-deps \
+		$PHPIZE_DEPS \
+		argon2-dev \
+		coreutils \
+		curl-dev \
+		libedit-dev \
+		libsodium-dev \
+		libxml2-dev \
+		linux-headers \
+		oniguruma-dev \
+		openssl-dev \
+		sqlite-dev \
+	; \
+	\
+	export CFLAGS="$PHP_CFLAGS" \
+		CPPFLAGS="$PHP_CPPFLAGS" \
+		LDFLAGS="$PHP_LDFLAGS" \
+	; \
+	docker-php-source extract; \
+	cd /usr/src/php; \
+	gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)"; \
+	./configure \
+		--build="$gnuArch" \
+		--with-config-file-path="$PHP_INI_DIR" \
+		--with-config-file-scan-dir="$PHP_INI_DIR/conf.d" \
+		\
+# make sure invalid --configure-flags are fatal errors instead of just warnings
+		--enable-option-checking=fatal \
+		\
+# https://github.com/docker-library/php/issues/439
+		--with-mhash \
+		\
+# https://github.com/docker-library/php/issues/822
+		--with-pic \
+		\
+# --enable-ftp is included here because ftp_ssl_connect() needs ftp to be compiled statically (see https://github.com/docker-library/php/issues/236)
+		--enable-ftp \
+# --enable-mbstring is included here because otherwise there's no way to get pecl to use it properly (see https://github.com/docker-library/php/issues/195)
+		--enable-mbstring \
+# --enable-mysqlnd is included here because it's harder to compile after the fact than extensions are (since it's a plugin for several extensions, not an extension in itself)
+		--enable-mysqlnd \
+# https://wiki.php.net/rfc/argon2_password_hash (7.2+)
+		--with-password-argon2 \
+# https://wiki.php.net/rfc/libsodium
+		--with-sodium=shared \
+# always build against system sqlite3 (https://github.com/php/php-src/commit/6083a387a81dbbd66d6316a3a12a63f06d5f7109)
+		--with-pdo-sqlite=/usr \
+		--with-sqlite3=/usr \
+		\
+		--with-curl \
+		--with-libedit \
+		--with-openssl \
+		--with-zlib \
+		\
+# in PHP 7.4+, the pecl/pear installers are officially deprecated (requiring an explicit "--with-pear")
+		--with-pear \
+		\
+# bundled pcre does not support JIT on s390x
+# https://manpages.debian.org/stretch/libpcre3-dev/pcrejit.3.en.html#AVAILABILITY_OF_JIT_SUPPORT
+		$(test "$gnuArch" = 's390x-linux-musl' && echo '--without-pcre-jit') \
+		\
+		${PHP_EXTRA_CONFIGURE_ARGS:-} \
+	; \
+	make -j "$(nproc)"; \
+	find -type f -name '*.a' -delete; \
+	make install; \
+	find /usr/local/bin /usr/local/sbin -type f -perm +0111 -exec strip --strip-all '{}' + || true; \
+	make clean; \
+	\
+# https://github.com/docker-library/php/issues/692 (copy default example "php.ini" files somewhere easily discoverable)
+	cp -v php.ini-* "$PHP_INI_DIR/"; \
+	\
+	cd /; \
+	docker-php-source delete; \
+	\
+	runDeps="$( \
+		scanelf --needed --nobanner --format '%n#p' --recursive /usr/local \
+			| tr ',' '\n' \
+			| sort -u \
+			| awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
+	)"; \
+	apk add --no-cache $runDeps; \
+	\
+	apk del --no-network .build-deps; \
+	\
+# update pecl channel definitions https://github.com/docker-library/php/issues/443
+	pecl update-channels; \
+	rm -rf /tmp/pear ~/.pearrc; \
+	\
+# smoke test
+	php --version
+
+COPY docker-php-ext-* docker-php-entrypoint /usr/local/bin/
+
+# sodium was built as a shared module (so that it can be replaced later if so desired), so let's enable it too (https://github.com/docker-library/php/issues/598)
+RUN docker-php-ext-enable sodium
+
+ENTRYPOINT ["docker-php-entrypoint"]
+CMD ["php", "-a"]
diff --git a/docker-php-entrypoint b/docker-php-entrypoint
new file mode 100755
index 0000000..88a016c
--- /dev/null
+++ b/docker-php-entrypoint
@@ -0,0 +1,9 @@
+#!/bin/sh
+set -e
+
+# first arg is `-f` or `--some-option`
+if [ "${1#-}" != "$1" ]; then
+	set -- php "$@"
+fi
+
+exec "$@"
diff --git a/docker-php-ext-configure b/docker-php-ext-configure
new file mode 100755
index 0000000..34fc133
--- /dev/null
+++ b/docker-php-ext-configure
@@ -0,0 +1,69 @@
+#!/bin/sh
+set -e
+
+# prefer user supplied CFLAGS, but default to our PHP_CFLAGS
+: ${CFLAGS:=$PHP_CFLAGS}
+: ${CPPFLAGS:=$PHP_CPPFLAGS}
+: ${LDFLAGS:=$PHP_LDFLAGS}
+export CFLAGS CPPFLAGS LDFLAGS
+
+srcExists=
+if [ -d /usr/src/php ]; then
+	srcExists=1
+fi
+docker-php-source extract
+if [ -z "$srcExists" ]; then
+	touch /usr/src/php/.docker-delete-me
+fi
+
+cd /usr/src/php/ext
+
+usage() {
+	echo "usage: $0 ext-name [configure flags]"
+	echo "   ie: $0 gd --with-jpeg-dir=/usr/local/something"
+	echo
+	echo 'Possible values for ext-name:'
+	find . \
+			-mindepth 2 \
+			-maxdepth 2 \
+			-type f \
+			-name 'config.m4' \
+		| xargs -n1 dirname \
+		| xargs -n1 basename \
+		| sort \
+		| xargs
+	echo
+	echo 'Some of the above modules are already compiled into PHP; please check'
+	echo 'the output of "php -i" to see which modules are already loaded.'
+}
+
+ext="$1"
+if [ -z "$ext" ] || [ ! -d "$ext" ]; then
+	usage >&2
+	exit 1
+fi
+shift
+
+pm='unknown'
+if [ -e /lib/apk/db/installed ]; then
+	pm='apk'
+fi
+
+if [ "$pm" = 'apk' ]; then
+	if \
+		[ -n "$PHPIZE_DEPS" ] \
+		&& ! apk info --installed .phpize-deps > /dev/null \
+		&& ! apk info --installed .phpize-deps-configure > /dev/null \
+	; then
+		apk add --no-cache --virtual .phpize-deps-configure $PHPIZE_DEPS
+	fi
+fi
+
+if command -v dpkg-architecture > /dev/null; then
+	gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)"
+	set -- --build="$gnuArch" "$@"
+fi
+
+cd "$ext"
+phpize
+./configure --enable-option-checking=fatal "$@"
diff --git a/docker-php-ext-enable b/docker-php-ext-enable
new file mode 100755
index 0000000..41d20bb
--- /dev/null
+++ b/docker-php-ext-enable
@@ -0,0 +1,121 @@
+#!/bin/sh
+set -e
+
+extDir="$(php -d 'display_errors=stderr' -r 'echo ini_get("extension_dir");')"
+cd "$extDir"
+
+usage() {
+	echo "usage: $0 [options] module-name [module-name ...]"
+	echo "   ie: $0 gd mysqli"
+	echo "       $0 pdo pdo_mysql"
+	echo "       $0 --ini-name 0-apc.ini apcu apc"
+	echo
+	echo 'Possible values for module-name:'
+	find -maxdepth 1 \
+			-type f \
+			-name '*.so' \
+			-exec basename '{}' ';' \
+		| sort \
+		| xargs
+	echo
+	echo 'Some of the above modules are already compiled into PHP; please check'
+	echo 'the output of "php -i" to see which modules are already loaded.'
+}
+
+opts="$(getopt -o 'h?' --long 'help,ini-name:' -- "$@" || { usage >&2 && false; })"
+eval set -- "$opts"
+
+iniName=
+while true; do
+	flag="$1"
+	shift
+	case "$flag" in
+		--help|-h|'-?') usage && exit 0 ;;
+		--ini-name) iniName="$1" && shift ;;
+		--) break ;;
+		*)
+			{
+				echo "error: unknown flag: $flag"
+				usage
+			} >&2
+			exit 1
+			;;
+	esac
+done
+
+modules=
+for module; do
+	if [ -z "$module" ]; then
+		continue
+	fi
+	if ! [ -f "$module" ] && ! [ -f "$module.so" ]; then
+		echo >&2 "error: '$module' does not exist"
+		echo >&2
+		usage >&2
+		exit 1
+	fi
+	modules="$modules $module"
+done
+
+if [ -z "$modules" ]; then
+	usage >&2
+	exit 1
+fi
+
+pm='unknown'
+if [ -e /lib/apk/db/installed ]; then
+	pm='apk'
+fi
+
+apkDel=
+if [ "$pm" = 'apk' ]; then
+	if \
+		[ -n "$PHPIZE_DEPS" ] \
+		&& ! apk info --installed .phpize-deps > /dev/null \
+		&& ! apk info --installed .phpize-deps-configure > /dev/null \
+	; then
+		apk add --no-cache --virtual '.docker-php-ext-enable-deps' binutils
+		apkDel='.docker-php-ext-enable-deps'
+	fi
+fi
+
+for module in $modules; do
+	moduleFile="$module"
+	if [ -f "$module.so" ] && ! [ -f "$module" ]; then
+		moduleFile="$module.so"
+	fi
+	if readelf --wide --syms "$moduleFile" | grep -q ' zend_extension_entry$'; then
+		# https://wiki.php.net/internals/extensions#loading_zend_extensions
+		line="zend_extension=$module"
+	else
+		line="extension=$module"
+	fi
+
+	ext="$(basename "$module")"
+	ext="${ext%.*}"
+	if php -d 'display_errors=stderr' -r 'exit(extension_loaded("'"$ext"'") ? 0 : 1);'; then
+		# this isn't perfect, but it's better than nothing
+		# (for example, 'opcache.so' presents inside PHP as 'Zend OPcache', not 'opcache')
+		echo >&2
+		echo >&2 "warning: $ext ($module) is already loaded!"
+		echo >&2
+		continue
+	fi
+
+	case "$iniName" in
+		/*)
+			# allow an absolute path
+			ini="$iniName"
+			;;
+		*)
+			ini="$PHP_INI_DIR/conf.d/${iniName:-"docker-php-ext-$ext.ini"}"
+			;;
+	esac
+	if ! grep -qFx -e "$line" -e "$line.so" "$ini" 2>/dev/null; then
+		echo "$line" >> "$ini"
+	fi
+done
+
+if [ "$pm" = 'apk' ] && [ -n "$apkDel" ]; then
+	apk del --no-network $apkDel
+fi
diff --git a/docker-php-ext-install b/docker-php-ext-install
new file mode 100755
index 0000000..f377be4
--- /dev/null
+++ b/docker-php-ext-install
@@ -0,0 +1,124 @@
+#!/bin/sh
+set -e
+
+# prefer user supplied CFLAGS, but default to our PHP_CFLAGS
+: ${CFLAGS:=$PHP_CFLAGS}
+: ${CPPFLAGS:=$PHP_CPPFLAGS}
+: ${LDFLAGS:=$PHP_LDFLAGS}
+export CFLAGS CPPFLAGS LDFLAGS
+
+srcExists=
+if [ -d /usr/src/php ]; then
+	srcExists=1
+fi
+docker-php-source extract
+if [ -z "$srcExists" ]; then
+	touch /usr/src/php/.docker-delete-me
+fi
+
+cd /usr/src/php/ext
+
+usage() {
+	echo "usage: $0 [-jN] [--ini-name file.ini] ext-name [ext-name ...]"
+	echo "   ie: $0 gd mysqli"
+	echo "       $0 pdo pdo_mysql"
+	echo "       $0 -j5 gd mbstring mysqli pdo pdo_mysql shmop"
+	echo
+	echo 'if custom ./configure arguments are necessary, see docker-php-ext-configure'
+	echo
+	echo 'Possible values for ext-name:'
+	find . \
+			-mindepth 2 \
+			-maxdepth 2 \
+			-type f \
+			-name 'config.m4' \
+		| xargs -n1 dirname \
+		| xargs -n1 basename \
+		| sort \
+		| xargs
+	echo
+	echo 'Some of the above modules are already compiled into PHP; please check'
+	echo 'the output of "php -i" to see which modules are already loaded.'
+}
+
+opts="$(getopt -o 'h?j:' --long 'help,ini-name:,jobs:' -- "$@" || { usage >&2 && false; })"
+eval set -- "$opts"
+
+j=1
+iniName=
+while true; do
+	flag="$1"
+	shift
+	case "$flag" in
+		--help|-h|'-?') usage && exit 0 ;;
+		--ini-name) iniName="$1" && shift ;;
+		--jobs|-j) j="$1" && shift ;;
+		--) break ;;
+		*)
+			{
+				echo "error: unknown flag: $flag"
+				usage
+			} >&2
+			exit 1
+			;;
+	esac
+done
+
+exts=
+for ext; do
+	if [ -z "$ext" ]; then
+		continue
+	fi
+	if [ ! -d "$ext" ]; then
+		echo >&2 "error: $PWD/$ext does not exist"
+		echo >&2
+		usage >&2
+		exit 1
+	fi
+	exts="$exts $ext"
+done
+
+if [ -z "$exts" ]; then
+	usage >&2
+	exit 1
+fi
+
+pm='unknown'
+if [ -e /lib/apk/db/installed ]; then
+	pm='apk'
+fi
+
+apkDel=
+if [ "$pm" = 'apk' ]; then
+	if [ -n "$PHPIZE_DEPS" ]; then
+		if apk info --installed .phpize-deps-configure > /dev/null; then
+			apkDel='.phpize-deps-configure'
+		elif ! apk info --installed .phpize-deps > /dev/null; then
+			apk add --no-cache --virtual .phpize-deps $PHPIZE_DEPS
+			apkDel='.phpize-deps'
+		fi
+	fi
+fi
+
+popDir="$PWD"
+for ext in $exts; do
+	cd "$ext"
+	[ -e Makefile ] || docker-php-ext-configure "$ext"
+	make -j"$j"
+	make -j"$j" install
+	find modules \
+		-maxdepth 1 \
+		-name '*.so' \
+		-exec basename '{}' ';' \
+			| xargs -r docker-php-ext-enable ${iniName:+--ini-name "$iniName"}
+	make -j"$j" clean
+	cd "$popDir"
+done
+
+if [ "$pm" = 'apk' ] && [ -n "$apkDel" ]; then
+	apk del --no-network $apkDel
+fi
+
+if [ -e /usr/src/php/.docker-delete-me ]; then
+	docker-php-source delete
+fi
diff --git a/docker-php-source b/docker-php-source
new file mode 100755
index 0000000..9033d24
--- /dev/null
+++ b/docker-php-source
@@ -0,0 +1,34 @@
+#!/bin/sh
+set -e
+
+dir=/usr/src/php
+
+usage() {
+	echo "usage: $0 COMMAND"
+	echo
+	echo "Manage php source tarball lifecycle."
+	echo
+	echo "Commands:"
+	echo "   extract  extract php source tarball into directory $dir if not already done."
+	echo "   delete   delete extracted php source located into $dir if not already done."
+	echo
+}
+
+case "$1" in
+	extract)
+		mkdir -p "$dir"
+		if [ ! -f "$dir/.docker-extracted" ]; then
+			tar -Jxf /usr/src/php.tar.xz -C "$dir" --strip-components=1
+			touch "$dir/.docker-extracted"
+		fi
+		;;
+
+	delete)
+		rm -rf "$dir"
+		;;
+
+	*)
+		usage
+		exit 1
+		;;
+esac