diff --git a/.travis.yml b/.travis.yml
index 8a8504860..14c075df4 100644
--- a/.travis.yml
+++ b/.travis.yml
@@ -7,13 +7,11 @@ matrix:
       dist: 1803-containers
       env: VERSION=3.8-rc VARIANT=windows/windowsservercore-1803
     - os: linux
-      env: VERSION=3.8-rc VARIANT=stretch
+      env: VERSION=3.8-rc VARIANT=buster
     - os: linux
-      env: VERSION=3.8-rc VARIANT=stretch/slim
+      env: VERSION=3.8-rc VARIANT=buster/slim
     - os: linux
       env: VERSION=3.8-rc VARIANT=alpine3.10
-    - os: linux
-      env: VERSION=3.8-rc VARIANT=alpine3.9
     - os: windows
       dist: 1803-containers
       env: VERSION=3.7 VARIANT=windows/windowsservercore-1803
diff --git a/2.7/alpine3.8/Dockerfile b/2.7/alpine3.8/Dockerfile
deleted file mode 100644
index a394fb56c..000000000
--- a/2.7/alpine3.8/Dockerfile
+++ /dev/null
@@ -1,121 +0,0 @@
-#
-# NOTE: THIS DOCKERFILE IS GENERATED VIA "update.sh"
-#
-# PLEASE DO NOT EDIT IT DIRECTLY.
-#
-
-FROM alpine:3.8
-
-# ensure local python is preferred over distribution python
-ENV PATH /usr/local/bin:$PATH
-
-# http://bugs.python.org/issue19846
-# > At the moment, setting "LANG=C" on a Linux system *fundamentally breaks Python 3*, and that's not OK.
-ENV LANG C.UTF-8
-# https://github.com/docker-library/python/issues/147
-ENV PYTHONIOENCODING UTF-8
-
-# install ca-certificates so that HTTPS works consistently
-# other runtime dependencies for Python are installed later
-RUN apk add --no-cache ca-certificates
-
-ENV GPG_KEY C01E1CAD5EA2C4F0B8E3571504C367C218ADD4FF
-ENV PYTHON_VERSION 2.7.16
-
-RUN set -ex \
-	&& apk add --no-cache --virtual .fetch-deps \
-		gnupg \
-		tar \
-		xz \
-	\
-	&& wget -O python.tar.xz "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz" \
-	&& wget -O python.tar.xz.asc "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz.asc" \
-	&& export GNUPGHOME="$(mktemp -d)" \
-	&& gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$GPG_KEY" \
-	&& gpg --batch --verify python.tar.xz.asc python.tar.xz \
-	&& { command -v gpgconf > /dev/null && gpgconf --kill all || :; } \
-	&& rm -rf "$GNUPGHOME" python.tar.xz.asc \
-	&& mkdir -p /usr/src/python \
-	&& tar -xJC /usr/src/python --strip-components=1 -f python.tar.xz \
-	&& rm python.tar.xz \
-	\
-	&& apk add --no-cache --virtual .build-deps  \
-		bzip2-dev \
-		coreutils \
-		dpkg-dev dpkg \
-		expat-dev \
-		findutils \
-		gcc \
-		gdbm-dev \
-		libc-dev \
-		libffi-dev \
-		libnsl-dev \
-		libtirpc-dev \
-		linux-headers \
-		make \
-		ncurses-dev \
-		libressl-dev \
-		pax-utils \
-		readline-dev \
-		sqlite-dev \
-		tcl-dev \
-		tk \
-		tk-dev \
-		zlib-dev \
-# add build deps before removing fetch deps in case there's overlap
-	&& apk del .fetch-deps \
-	\
-	&& cd /usr/src/python \
-	&& gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)" \
-	&& ./configure \
-		--build="$gnuArch" \
-		--enable-shared \
-		--enable-unicode=ucs4 \
-		--with-system-expat \
-		--with-system-ffi \
-	&& make -j "$(nproc)" \
-# set thread stack size to 1MB so we don't segfault before we hit sys.getrecursionlimit()
-# https://github.com/alpinelinux/aports/commit/2026e1259422d4e0cf92391ca2d3844356c649d0
-		EXTRA_CFLAGS="-DTHREAD_STACK_SIZE=0x100000" \
-	&& make install \
-	\
-	&& find /usr/local -type f -executable -not \( -name '*tkinter*' \) -exec scanelf --needed --nobanner --format '%n#p' '{}' ';' \
-		| tr ',' '\n' \
-		| sort -u \
-		| awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
-		| xargs -rt apk add --no-cache --virtual .python-rundeps \
-	&& apk del .build-deps \
-	\
-	&& find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' + \
-	&& rm -rf /usr/src/python \
-	\
-	&& python2 --version
-
-# if this is called "PIP_VERSION", pip explodes with "ValueError: invalid truth value '<VERSION>'"
-ENV PYTHON_PIP_VERSION 19.1.1
-
-RUN set -ex; \
-	\
-	wget -O get-pip.py 'https://bootstrap.pypa.io/get-pip.py'; \
-	\
-	python get-pip.py \
-		--disable-pip-version-check \
-		--no-cache-dir \
-		"pip==$PYTHON_PIP_VERSION" \
-	; \
-	pip --version; \
-	\
-	find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' +; \
-	rm -f get-pip.py
-
-CMD ["python2"]
diff --git a/3.5/alpine3.8/Dockerfile b/3.5/alpine3.8/Dockerfile
deleted file mode 100644
index e371bf8a5..000000000
--- a/3.5/alpine3.8/Dockerfile
+++ /dev/null
@@ -1,126 +0,0 @@
-#
-# NOTE: THIS DOCKERFILE IS GENERATED VIA "update.sh"
-#
-# PLEASE DO NOT EDIT IT DIRECTLY.
-#
-
-FROM alpine:3.8
-
-# ensure local python is preferred over distribution python
-ENV PATH /usr/local/bin:$PATH
-
-# http://bugs.python.org/issue19846
-# > At the moment, setting "LANG=C" on a Linux system *fundamentally breaks Python 3*, and that's not OK.
-ENV LANG C.UTF-8
-
-# install ca-certificates so that HTTPS works consistently
-# other runtime dependencies for Python are installed later
-RUN apk add --no-cache ca-certificates
-
-ENV GPG_KEY 97FC712E4C024BBEA48A61ED3A5CA953F73C700D
-ENV PYTHON_VERSION 3.5.7
-
-RUN set -ex \
-	&& apk add --no-cache --virtual .fetch-deps \
-		gnupg \
-		tar \
-		xz \
-	\
-	&& wget -O python.tar.xz "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz" \
-	&& wget -O python.tar.xz.asc "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz.asc" \
-	&& export GNUPGHOME="$(mktemp -d)" \
-	&& gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$GPG_KEY" \
-	&& gpg --batch --verify python.tar.xz.asc python.tar.xz \
-	&& { command -v gpgconf > /dev/null && gpgconf --kill all || :; } \
-	&& rm -rf "$GNUPGHOME" python.tar.xz.asc \
-	&& mkdir -p /usr/src/python \
-	&& tar -xJC /usr/src/python --strip-components=1 -f python.tar.xz \
-	&& rm python.tar.xz \
-	\
-	&& apk add --no-cache --virtual .build-deps  \
-		bzip2-dev \
-		coreutils \
-		dpkg-dev dpkg \
-		expat-dev \
-		findutils \
-		gcc \
-		gdbm-dev \
-		libc-dev \
-		libffi-dev \
-		linux-headers \
-		make \
-		ncurses-dev \
-		openssl-dev \
-		pax-utils \
-		readline-dev \
-		sqlite-dev \
-		tcl-dev \
-		tk \
-		tk-dev \
-		xz-dev \
-		zlib-dev \
-# add build deps before removing fetch deps in case there's overlap
-	&& apk del .fetch-deps \
-	\
-	&& cd /usr/src/python \
-	&& gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)" \
-	&& ./configure \
-		--build="$gnuArch" \
-		--enable-loadable-sqlite-extensions \
-		--enable-shared \
-		--with-system-expat \
-		--with-system-ffi \
-		--without-ensurepip \
-	&& make -j "$(nproc)" \
-# set thread stack size to 1MB so we don't segfault before we hit sys.getrecursionlimit()
-# https://github.com/alpinelinux/aports/commit/2026e1259422d4e0cf92391ca2d3844356c649d0
-		EXTRA_CFLAGS="-DTHREAD_STACK_SIZE=0x100000" \
-	&& make install \
-	\
-	&& find /usr/local -type f -executable -not \( -name '*tkinter*' \) -exec scanelf --needed --nobanner --format '%n#p' '{}' ';' \
-		| tr ',' '\n' \
-		| sort -u \
-		| awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
-		| xargs -rt apk add --no-cache --virtual .python-rundeps \
-	&& apk del .build-deps \
-	\
-	&& find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' + \
-	&& rm -rf /usr/src/python \
-	\
-	&& python3 --version
-
-# make some useful symlinks that are expected to exist
-RUN cd /usr/local/bin \
-	&& ln -s idle3 idle \
-	&& ln -s pydoc3 pydoc \
-	&& ln -s python3 python \
-	&& ln -s python3-config python-config
-
-# if this is called "PIP_VERSION", pip explodes with "ValueError: invalid truth value '<VERSION>'"
-ENV PYTHON_PIP_VERSION 19.1.1
-
-RUN set -ex; \
-	\
-	wget -O get-pip.py 'https://bootstrap.pypa.io/get-pip.py'; \
-	\
-	python get-pip.py \
-		--disable-pip-version-check \
-		--no-cache-dir \
-		"pip==$PYTHON_PIP_VERSION" \
-	; \
-	pip --version; \
-	\
-	find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' +; \
-	rm -f get-pip.py
-
-CMD ["python3"]
diff --git a/3.6/alpine3.8/Dockerfile b/3.6/alpine3.8/Dockerfile
deleted file mode 100644
index f12f3f99f..000000000
--- a/3.6/alpine3.8/Dockerfile
+++ /dev/null
@@ -1,128 +0,0 @@
-#
-# NOTE: THIS DOCKERFILE IS GENERATED VIA "update.sh"
-#
-# PLEASE DO NOT EDIT IT DIRECTLY.
-#
-
-FROM alpine:3.8
-
-# ensure local python is preferred over distribution python
-ENV PATH /usr/local/bin:$PATH
-
-# http://bugs.python.org/issue19846
-# > At the moment, setting "LANG=C" on a Linux system *fundamentally breaks Python 3*, and that's not OK.
-ENV LANG C.UTF-8
-
-# install ca-certificates so that HTTPS works consistently
-# other runtime dependencies for Python are installed later
-RUN apk add --no-cache ca-certificates
-
-ENV GPG_KEY 0D96DF4D4110E5C43FBFB17F2D347EA6AA65421D
-ENV PYTHON_VERSION 3.6.8
-
-RUN set -ex \
-	&& apk add --no-cache --virtual .fetch-deps \
-		gnupg \
-		tar \
-		xz \
-	\
-	&& wget -O python.tar.xz "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz" \
-	&& wget -O python.tar.xz.asc "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz.asc" \
-	&& export GNUPGHOME="$(mktemp -d)" \
-	&& gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$GPG_KEY" \
-	&& gpg --batch --verify python.tar.xz.asc python.tar.xz \
-	&& { command -v gpgconf > /dev/null && gpgconf --kill all || :; } \
-	&& rm -rf "$GNUPGHOME" python.tar.xz.asc \
-	&& mkdir -p /usr/src/python \
-	&& tar -xJC /usr/src/python --strip-components=1 -f python.tar.xz \
-	&& rm python.tar.xz \
-	\
-	&& apk add --no-cache --virtual .build-deps  \
-		bzip2-dev \
-		coreutils \
-		dpkg-dev dpkg \
-		expat-dev \
-		findutils \
-		gcc \
-		gdbm-dev \
-		libc-dev \
-		libffi-dev \
-		libnsl-dev \
-		libtirpc-dev \
-		linux-headers \
-		make \
-		ncurses-dev \
-		libressl-dev \
-		pax-utils \
-		readline-dev \
-		sqlite-dev \
-		tcl-dev \
-		tk \
-		tk-dev \
-		xz-dev \
-		zlib-dev \
-# add build deps before removing fetch deps in case there's overlap
-	&& apk del .fetch-deps \
-	\
-	&& cd /usr/src/python \
-	&& gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)" \
-	&& ./configure \
-		--build="$gnuArch" \
-		--enable-loadable-sqlite-extensions \
-		--enable-shared \
-		--with-system-expat \
-		--with-system-ffi \
-		--without-ensurepip \
-	&& make -j "$(nproc)" \
-# set thread stack size to 1MB so we don't segfault before we hit sys.getrecursionlimit()
-# https://github.com/alpinelinux/aports/commit/2026e1259422d4e0cf92391ca2d3844356c649d0
-		EXTRA_CFLAGS="-DTHREAD_STACK_SIZE=0x100000" \
-	&& make install \
-	\
-	&& find /usr/local -type f -executable -not \( -name '*tkinter*' \) -exec scanelf --needed --nobanner --format '%n#p' '{}' ';' \
-		| tr ',' '\n' \
-		| sort -u \
-		| awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
-		| xargs -rt apk add --no-cache --virtual .python-rundeps \
-	&& apk del .build-deps \
-	\
-	&& find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' + \
-	&& rm -rf /usr/src/python \
-	\
-	&& python3 --version
-
-# make some useful symlinks that are expected to exist
-RUN cd /usr/local/bin \
-	&& ln -s idle3 idle \
-	&& ln -s pydoc3 pydoc \
-	&& ln -s python3 python \
-	&& ln -s python3-config python-config
-
-# if this is called "PIP_VERSION", pip explodes with "ValueError: invalid truth value '<VERSION>'"
-ENV PYTHON_PIP_VERSION 19.1.1
-
-RUN set -ex; \
-	\
-	wget -O get-pip.py 'https://bootstrap.pypa.io/get-pip.py'; \
-	\
-	python get-pip.py \
-		--disable-pip-version-check \
-		--no-cache-dir \
-		"pip==$PYTHON_PIP_VERSION" \
-	; \
-	pip --version; \
-	\
-	find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' +; \
-	rm -f get-pip.py
-
-CMD ["python3"]
diff --git a/3.7/alpine3.8/Dockerfile b/3.7/alpine3.8/Dockerfile
deleted file mode 100644
index 2822cecdb..000000000
--- a/3.7/alpine3.8/Dockerfile
+++ /dev/null
@@ -1,129 +0,0 @@
-#
-# NOTE: THIS DOCKERFILE IS GENERATED VIA "update.sh"
-#
-# PLEASE DO NOT EDIT IT DIRECTLY.
-#
-
-FROM alpine:3.8
-
-# ensure local python is preferred over distribution python
-ENV PATH /usr/local/bin:$PATH
-
-# http://bugs.python.org/issue19846
-# > At the moment, setting "LANG=C" on a Linux system *fundamentally breaks Python 3*, and that's not OK.
-ENV LANG C.UTF-8
-
-# install ca-certificates so that HTTPS works consistently
-# other runtime dependencies for Python are installed later
-RUN apk add --no-cache ca-certificates
-
-ENV GPG_KEY 0D96DF4D4110E5C43FBFB17F2D347EA6AA65421D
-ENV PYTHON_VERSION 3.7.3
-
-RUN set -ex \
-	&& apk add --no-cache --virtual .fetch-deps \
-		gnupg \
-		tar \
-		xz \
-	\
-	&& wget -O python.tar.xz "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz" \
-	&& wget -O python.tar.xz.asc "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz.asc" \
-	&& export GNUPGHOME="$(mktemp -d)" \
-	&& gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$GPG_KEY" \
-	&& gpg --batch --verify python.tar.xz.asc python.tar.xz \
-	&& { command -v gpgconf > /dev/null && gpgconf --kill all || :; } \
-	&& rm -rf "$GNUPGHOME" python.tar.xz.asc \
-	&& mkdir -p /usr/src/python \
-	&& tar -xJC /usr/src/python --strip-components=1 -f python.tar.xz \
-	&& rm python.tar.xz \
-	\
-	&& apk add --no-cache --virtual .build-deps  \
-		bzip2-dev \
-		coreutils \
-		dpkg-dev dpkg \
-		expat-dev \
-		findutils \
-		gcc \
-		gdbm-dev \
-		libc-dev \
-		libffi-dev \
-		libnsl-dev \
-		libtirpc-dev \
-		linux-headers \
-		make \
-		ncurses-dev \
-		libressl-dev \
-		pax-utils \
-		readline-dev \
-		sqlite-dev \
-		tcl-dev \
-		tk \
-		tk-dev \
-		util-linux-dev \
-		xz-dev \
-		zlib-dev \
-# add build deps before removing fetch deps in case there's overlap
-	&& apk del .fetch-deps \
-	\
-	&& cd /usr/src/python \
-	&& gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)" \
-	&& ./configure \
-		--build="$gnuArch" \
-		--enable-loadable-sqlite-extensions \
-		--enable-shared \
-		--with-system-expat \
-		--with-system-ffi \
-		--without-ensurepip \
-	&& make -j "$(nproc)" \
-# set thread stack size to 1MB so we don't segfault before we hit sys.getrecursionlimit()
-# https://github.com/alpinelinux/aports/commit/2026e1259422d4e0cf92391ca2d3844356c649d0
-		EXTRA_CFLAGS="-DTHREAD_STACK_SIZE=0x100000" \
-	&& make install \
-	\
-	&& find /usr/local -type f -executable -not \( -name '*tkinter*' \) -exec scanelf --needed --nobanner --format '%n#p' '{}' ';' \
-		| tr ',' '\n' \
-		| sort -u \
-		| awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
-		| xargs -rt apk add --no-cache --virtual .python-rundeps \
-	&& apk del .build-deps \
-	\
-	&& find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' + \
-	&& rm -rf /usr/src/python \
-	\
-	&& python3 --version
-
-# make some useful symlinks that are expected to exist
-RUN cd /usr/local/bin \
-	&& ln -s idle3 idle \
-	&& ln -s pydoc3 pydoc \
-	&& ln -s python3 python \
-	&& ln -s python3-config python-config
-
-# if this is called "PIP_VERSION", pip explodes with "ValueError: invalid truth value '<VERSION>'"
-ENV PYTHON_PIP_VERSION 19.1.1
-
-RUN set -ex; \
-	\
-	wget -O get-pip.py 'https://bootstrap.pypa.io/get-pip.py'; \
-	\
-	python get-pip.py \
-		--disable-pip-version-check \
-		--no-cache-dir \
-		"pip==$PYTHON_PIP_VERSION" \
-	; \
-	pip --version; \
-	\
-	find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' +; \
-	rm -f get-pip.py
-
-CMD ["python3"]
diff --git a/3.8-rc/alpine3.9/Dockerfile b/3.8-rc/alpine3.9/Dockerfile
deleted file mode 100644
index 2eb792802..000000000
--- a/3.8-rc/alpine3.9/Dockerfile
+++ /dev/null
@@ -1,129 +0,0 @@
-#
-# NOTE: THIS DOCKERFILE IS GENERATED VIA "update.sh"
-#
-# PLEASE DO NOT EDIT IT DIRECTLY.
-#
-
-FROM alpine:3.9
-
-# ensure local python is preferred over distribution python
-ENV PATH /usr/local/bin:$PATH
-
-# http://bugs.python.org/issue19846
-# > At the moment, setting "LANG=C" on a Linux system *fundamentally breaks Python 3*, and that's not OK.
-ENV LANG C.UTF-8
-
-# install ca-certificates so that HTTPS works consistently
-# other runtime dependencies for Python are installed later
-RUN apk add --no-cache ca-certificates
-
-ENV GPG_KEY E3FF2839C048B25C084DEBE9B26995E310250568
-ENV PYTHON_VERSION 3.8.0b1
-
-RUN set -ex \
-	&& apk add --no-cache --virtual .fetch-deps \
-		gnupg \
-		tar \
-		xz \
-	\
-	&& wget -O python.tar.xz "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz" \
-	&& wget -O python.tar.xz.asc "https://www.python.org/ftp/python/${PYTHON_VERSION%%[a-z]*}/Python-$PYTHON_VERSION.tar.xz.asc" \
-	&& export GNUPGHOME="$(mktemp -d)" \
-	&& gpg --batch --keyserver ha.pool.sks-keyservers.net --recv-keys "$GPG_KEY" \
-	&& gpg --batch --verify python.tar.xz.asc python.tar.xz \
-	&& { command -v gpgconf > /dev/null && gpgconf --kill all || :; } \
-	&& rm -rf "$GNUPGHOME" python.tar.xz.asc \
-	&& mkdir -p /usr/src/python \
-	&& tar -xJC /usr/src/python --strip-components=1 -f python.tar.xz \
-	&& rm python.tar.xz \
-	\
-	&& apk add --no-cache --virtual .build-deps  \
-		bzip2-dev \
-		coreutils \
-		dpkg-dev dpkg \
-		expat-dev \
-		findutils \
-		gcc \
-		gdbm-dev \
-		libc-dev \
-		libffi-dev \
-		libnsl-dev \
-		libtirpc-dev \
-		linux-headers \
-		make \
-		ncurses-dev \
-		openssl-dev \
-		pax-utils \
-		readline-dev \
-		sqlite-dev \
-		tcl-dev \
-		tk \
-		tk-dev \
-		util-linux-dev \
-		xz-dev \
-		zlib-dev \
-# add build deps before removing fetch deps in case there's overlap
-	&& apk del .fetch-deps \
-	\
-	&& cd /usr/src/python \
-	&& gnuArch="$(dpkg-architecture --query DEB_BUILD_GNU_TYPE)" \
-	&& ./configure \
-		--build="$gnuArch" \
-		--enable-loadable-sqlite-extensions \
-		--enable-shared \
-		--with-system-expat \
-		--with-system-ffi \
-		--without-ensurepip \
-	&& make -j "$(nproc)" \
-# set thread stack size to 1MB so we don't segfault before we hit sys.getrecursionlimit()
-# https://github.com/alpinelinux/aports/commit/2026e1259422d4e0cf92391ca2d3844356c649d0
-		EXTRA_CFLAGS="-DTHREAD_STACK_SIZE=0x100000" \
-	&& make install \
-	\
-	&& find /usr/local -type f -executable -not \( -name '*tkinter*' \) -exec scanelf --needed --nobanner --format '%n#p' '{}' ';' \
-		| tr ',' '\n' \
-		| sort -u \
-		| awk 'system("[ -e /usr/local/lib/" $1 " ]") == 0 { next } { print "so:" $1 }' \
-		| xargs -rt apk add --no-cache --virtual .python-rundeps \
-	&& apk del .build-deps \
-	\
-	&& find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' + \
-	&& rm -rf /usr/src/python \
-	\
-	&& python3 --version
-
-# make some useful symlinks that are expected to exist
-RUN cd /usr/local/bin \
-	&& ln -s idle3 idle \
-	&& ln -s pydoc3 pydoc \
-	&& ln -s python3 python \
-	&& ln -s python3-config python-config
-
-# if this is called "PIP_VERSION", pip explodes with "ValueError: invalid truth value '<VERSION>'"
-ENV PYTHON_PIP_VERSION 19.1.1
-
-RUN set -ex; \
-	\
-	wget -O get-pip.py 'https://bootstrap.pypa.io/get-pip.py'; \
-	\
-	python get-pip.py \
-		--disable-pip-version-check \
-		--no-cache-dir \
-		"pip==$PYTHON_PIP_VERSION" \
-	; \
-	pip --version; \
-	\
-	find /usr/local -depth \
-		\( \
-			\( -type d -a \( -name test -o -name tests \) \) \
-			-o \
-			\( -type f -a \( -name '*.pyc' -o -name '*.pyo' \) \) \
-		\) -exec rm -rf '{}' +; \
-	rm -f get-pip.py
-
-CMD ["python3"]
diff --git a/3.8-rc/stretch/Dockerfile b/3.8-rc/buster/Dockerfile
similarity index 98%
rename from 3.8-rc/stretch/Dockerfile
rename to 3.8-rc/buster/Dockerfile
index 6a8a7d9bb..75151b7cb 100644
--- a/3.8-rc/stretch/Dockerfile
+++ b/3.8-rc/buster/Dockerfile
@@ -4,7 +4,7 @@
 # PLEASE DO NOT EDIT IT DIRECTLY.
 #
 
-FROM buildpack-deps:stretch
+FROM buildpack-deps:buster
 
 # ensure local python is preferred over distribution python
 ENV PATH /usr/local/bin:$PATH
diff --git a/3.8-rc/stretch/slim/Dockerfile b/3.8-rc/buster/slim/Dockerfile
similarity index 99%
rename from 3.8-rc/stretch/slim/Dockerfile
rename to 3.8-rc/buster/slim/Dockerfile
index f2c99f669..71db0614d 100644
--- a/3.8-rc/stretch/slim/Dockerfile
+++ b/3.8-rc/buster/slim/Dockerfile
@@ -4,7 +4,7 @@
 # PLEASE DO NOT EDIT IT DIRECTLY.
 #
 
-FROM debian:stretch-slim
+FROM debian:buster-slim
 
 # ensure local python is preferred over distribution python
 ENV PATH /usr/local/bin:$PATH
diff --git a/generate-stackbrew-library.sh b/generate-stackbrew-library.sh
index 1916e8499..9c0fc0c62 100755
--- a/generate-stackbrew-library.sh
+++ b/generate-stackbrew-library.sh
@@ -7,7 +7,10 @@ declare -A aliases=(
 	[2.7]='2'
 )
 
-defaultDebianSuite='stretch'
+defaultDebianSuite='stretch' # TODO buster
+declare -A debianSuites=(
+	[3.8-rc]='buster'
+)
 defaultAlpineVersion='3.10'
 
 self="$(basename "$BASH_SOURCE")"
@@ -77,6 +80,7 @@ for version in "${versions[@]}"; do
 
 	for v in \
 		{stretch,jessie}{,/slim} \
+		{buster,stretch,jessie}{,/slim} \
 		alpine{3.10,3.9} \
 		windows/windowsservercore-{ltsc2016,1803,1809} \
 	; do
@@ -102,9 +106,10 @@ for version in "${versions[@]}"; do
 		)
 
 		variantAliases=( "${versionAliases[@]/%/-$variant}" )
+		debianSuite="${debianSuites[$version]:-$defaultDebianSuite}"
 		case "$variant" in
-			*-"$defaultDebianSuite") # "slim-stretch", etc need "slim"
-				variantAliases+=( "${versionAliases[@]/%/-${variant%-$defaultDebianSuite}}" )
+			*-"$debianSuite") # "slim-stretch", etc need "slim"
+				variantAliases+=( "${versionAliases[@]/%/-${variant%-$debianSuite}}" )
 				;;
 			"alpine${defaultAlpineVersion}")
 				variantAliases+=( "${versionAliases[@]/%/-alpine}" )
@@ -128,7 +133,7 @@ for version in "${versions[@]}"; do
 				break
 			fi
 		done
-		if [ "$variant" = "$defaultDebianSuite" ] || [[ "$variant" == 'windowsservercore'* ]]; then
+		if [ "$variant" = "$debianSuite" ] || [[ "$variant" == 'windowsservercore'* ]]; then
 			sharedTags+=( "${versionAliases[@]}" )
 		fi
 
diff --git a/update.sh b/update.sh
index e8d22e5bd..c2bf2af46 100755
--- a/update.sh
+++ b/update.sh
@@ -114,7 +114,7 @@ for version in "${versions[@]}"; do
 
 	for v in \
 		alpine{3.9,3.10} \
-		{jessie,stretch}{/slim,} \
+		{jessie,stretch,buster}{/slim,} \
 		windows/windowsservercore-{1809,1803,ltsc2016} \
 	; do
 		dir="$version/$v"
@@ -164,7 +164,7 @@ for version in "${versions[@]}"; do
 			3.[5-6]*)
 				sed -ri -e '/uuid-dev/d' "$dir/Dockerfile"
 				;;& # (other Debian variants need to match later blocks)
-			*/stretch | */jessie)
+			*/buster | */stretch | */jessie)
 				# buildpack-deps already includes libssl-dev
 				sed -ri -e '/libssl-dev/d' "$dir/Dockerfile"
 				;;