diff --git a/Dockerfile-py2-amd64 b/Dockerfile-py2-amd64
index 6681f00..f82c1c7 100644
--- a/Dockerfile-py2-amd64
+++ b/Dockerfile-py2-amd64
@@ -1,5 +1,4 @@
-FROM ubuntu:12.04
-SHELL ["/bin/bash", "-i", "-c"]
+FROM ubuntu:18.04
 
 ARG PYTHON_VERSION=2.7.17
 ARG PYINSTALLER_VERSION=3.6
@@ -8,6 +7,10 @@ ENV PYPI_URL=https://pypi.python.org/
 ENV PYPI_INDEX_URL=https://pypi.python.org/simple
 ENV PYENV_VERSION=${PYTHON_VERSION}
 
+# set compilation environment for python
+ENV PYTHON_CONFIGURE_OPTS=--enable-shared
+ENV CPPFLAGS=-O2
+
 COPY entrypoint-linux.sh /entrypoint.sh
 
 RUN \
@@ -27,31 +30,25 @@ RUN \
         libssl-dev \
         zlib1g-dev \
         libffi-dev \
+        openssl \
         #optional libraries
         libgdbm-dev \
-        libgdbm3 \
+        # libgdbm5 for ubuntu 18.04
+        # libgdbm6 for ubuntu 20.04
+        libgdbm5 \
         uuid-dev \
         #upx
         upx \
-    # required because openSSL on Ubuntu 12.04 and 14.04 run out of support versions of OpenSSL
-    && mkdir openssl \
-    && cd openssl \
-    # latest version, there won't be anything newer for this
-    && wget https://www.openssl.org/source/openssl-1.0.2u.tar.gz \
-    && tar -xzvf openssl-1.0.2u.tar.gz \
-    && cd openssl-1.0.2u \
-    && ./config --prefix=$HOME/openssl --openssldir=$HOME/openssl shared zlib \
-    && make \
-    && make install \
     # install pyenv
     && echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bashrc \
     && echo 'export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc \
-    && source ~/.bashrc \
+    && . ~/.bashrc \
     && curl -L https://github.com/pyenv/pyenv-installer/raw/master/bin/pyenv-installer | bash \
     && echo 'eval "$(pyenv init -)"' >> ~/.bashrc \
-    && source ~/.bashrc \
+    && echo 'eval "$(pyenv init --path)"' >> ~/.bashrc \
+    && . ~/.bashrc \
     # install python
-    && PATH="$HOME/openssl:$PATH"  CPPFLAGS="-O2 -I$HOME/openssl/include" CFLAGS="-I$HOME/openssl/include/" LDFLAGS="-L$HOME/openssl/lib -Wl,-rpath,$HOME/openssl/lib" LD_LIBRARY_PATH=$HOME/openssl/lib:$LD_LIBRARY_PATH LD_RUN_PATH="$HOME/openssl/lib" CONFIGURE_OPTS="--with-openssl=$HOME/openssl" PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install $PYTHON_VERSION \
+    && pyenv install $PYTHON_VERSION \
     && pyenv global $PYTHON_VERSION \
     && pip install --upgrade pip \
     # install pyinstaller
diff --git a/Dockerfile-py2-win32 b/Dockerfile-py2-win32
index 1738f8a..ef2fa77 100644
--- a/Dockerfile-py2-win32
+++ b/Dockerfile-py2-win32
@@ -1,4 +1,4 @@
-FROM ubuntu:14.04
+FROM ubuntu:20.04
 
 ENV DEBIAN_FRONTEND noninteractive
 
diff --git a/Dockerfile-py3-amd64 b/Dockerfile-py3-amd64
index d2ba86e..88d346d 100644
--- a/Dockerfile-py3-amd64
+++ b/Dockerfile-py3-amd64
@@ -1,13 +1,16 @@
-FROM ubuntu:12.04
-SHELL ["/bin/bash", "-i", "-c"]
+FROM ubuntu:18.04
 
-ARG PYTHON_VERSION=3.7.5
-ARG PYINSTALLER_VERSION=3.6
+ARG PYTHON_VERSION=3.9.6
+ARG PYINSTALLER_VERSION=4.2
 
 ENV PYPI_URL=https://pypi.python.org/
 ENV PYPI_INDEX_URL=https://pypi.python.org/simple
 ENV PYENV_VERSION=${PYTHON_VERSION}
 
+# set compilation environment for python
+ENV PYTHON_CONFIGURE_OPTS=--enable-shared
+ENV CPPFLAGS=-O2
+
 COPY entrypoint-linux.sh /entrypoint.sh
 
 RUN \
@@ -27,31 +30,25 @@ RUN \
         libssl-dev \
         zlib1g-dev \
         libffi-dev \
+        openssl \
         #optional libraries
         libgdbm-dev \
-        libgdbm3 \
+        # libgdbm5 for ubuntu 18.04
+        # libgdbm6 for ubuntu 20.04
+        libgdbm5 \
         uuid-dev \
         #upx
         upx \
-    # required because openSSL on Ubuntu 12.04 and 14.04 run out of support versions of OpenSSL
-    && mkdir openssl \
-    && cd openssl \
-    # latest version, there won't be anything newer for this
-    && wget https://www.openssl.org/source/openssl-1.0.2u.tar.gz \
-    && tar -xzvf openssl-1.0.2u.tar.gz \
-    && cd openssl-1.0.2u \
-    && ./config --prefix=$HOME/openssl --openssldir=$HOME/openssl shared zlib \
-    && make \
-    && make install \
     # install pyenv
     && echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bashrc \
     && echo 'export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc \
-    && source ~/.bashrc \
+    && . ~/.bashrc \
     && curl -L https://github.com/pyenv/pyenv-installer/raw/master/bin/pyenv-installer | bash \
     && echo 'eval "$(pyenv init -)"' >> ~/.bashrc \
-    && source ~/.bashrc \
+    && echo 'eval "$(pyenv init --path)"' >> ~/.bashrc \
+    && . ~/.bashrc \
     # install python
-    && PATH="$HOME/openssl:$PATH"  CPPFLAGS="-O2 -I$HOME/openssl/include" CFLAGS="-I$HOME/openssl/include/" LDFLAGS="-L$HOME/openssl/lib -Wl,-rpath,$HOME/openssl/lib" LD_LIBRARY_PATH=$HOME/openssl/lib:$LD_LIBRARY_PATH LD_RUN_PATH="$HOME/openssl/lib" CONFIGURE_OPTS="--with-openssl=$HOME/openssl" PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install $PYTHON_VERSION \
+    && pyenv install $PYTHON_VERSION \
     && pyenv global $PYTHON_VERSION \
     && pip install --upgrade pip \
     # install pyinstaller
diff --git a/Dockerfile-py3-i386 b/Dockerfile-py3-i386
index 414ee56..b3e9482 100644
--- a/Dockerfile-py3-i386
+++ b/Dockerfile-py3-i386
@@ -1,13 +1,16 @@
-FROM i386/ubuntu:12.04
-SHELL ["/bin/bash", "-i", "-c"]
+FROM i386/ubuntu:18.04
 
-ARG PYTHON_VERSION=3.7.5
-ARG PYINSTALLER_VERSION=3.6
+ARG PYTHON_VERSION=3.9.6
+ARG PYINSTALLER_VERSION=4.2
 
 ENV PYPI_URL=https://pypi.python.org/
 ENV PYPI_INDEX_URL=https://pypi.python.org/simple
 ENV PYENV_VERSION=${PYTHON_VERSION}
 
+# set compilation environment for python
+ENV PYTHON_CONFIGURE_OPTS=--enable-shared
+ENV CPPFLAGS=-O2
+
 COPY entrypoint-linux.sh /entrypoint.sh
 
 RUN \
@@ -27,31 +30,25 @@ RUN \
         libssl-dev \
         zlib1g-dev \
         libffi-dev \
+        openssl \
         #optional libraries
         libgdbm-dev \
-        libgdbm3 \
+        # libgdbm5 for ubuntu 18.04
+        # libgdbm6 for ubuntu 20.04
+        libgdbm5 \
         uuid-dev \
-        #upx
+        #upx # why is this needed?
         upx \
-    # required because openSSL on Ubuntu 12.04 and 14.04 run out of support versions of OpenSSL
-    && mkdir openssl \
-    && cd openssl \
-    # latest version, there won't be anything newer for this
-    && wget https://www.openssl.org/source/openssl-1.0.2u.tar.gz \
-    && tar -xzvf openssl-1.0.2u.tar.gz \
-    && cd openssl-1.0.2u \
-    && ./Configure linux-generic32 --prefix=$HOME/openssl --openssldir=$HOME/openssl shared zlib \
-    && make \
-    && make install \
     # install pyenv
     && echo 'export PYENV_ROOT="$HOME/.pyenv"' >> ~/.bashrc \
     && echo 'export PATH="$PYENV_ROOT/bin:$PATH"' >> ~/.bashrc \
-    && source ~/.bashrc \
+    && . ~/.bashrc \
     && curl -L https://github.com/pyenv/pyenv-installer/raw/master/bin/pyenv-installer | bash \
     && echo 'eval "$(pyenv init -)"' >> ~/.bashrc \
-    && source ~/.bashrc \
+    && echo 'eval "$(pyenv init --path)"' >> ~/.bashrc \
+    && . ~/.bashrc \
     # install python
-    && PATH="$HOME/openssl:$PATH"  CPPFLAGS="-O2 -I$HOME/openssl/include" CFLAGS="-I$HOME/openssl/include/" LDFLAGS="-L$HOME/openssl/lib -Wl,-rpath,$HOME/openssl/lib" LD_LIBRARY_PATH=$HOME/openssl/lib:$LD_LIBRARY_PATH LD_RUN_PATH="$HOME/openssl/lib" CONFIGURE_OPTS="--with-openssl=$HOME/openssl" PYTHON_CONFIGURE_OPTS="--enable-shared" pyenv install $PYTHON_VERSION \
+    && pyenv install $PYTHON_VERSION \
     && pyenv global $PYTHON_VERSION \
     && pip install --upgrade pip \
     # install pyinstaller
diff --git a/Dockerfile-py3-win32 b/Dockerfile-py3-win32
index 89787b0..43a4af0 100644
--- a/Dockerfile-py3-win32
+++ b/Dockerfile-py3-win32
@@ -1,16 +1,16 @@
-FROM ubuntu:16.04
+FROM ubuntu:20.04
 
 ENV DEBIAN_FRONTEND noninteractive
 
 ARG WINE_VERSION=winehq-staging
-ARG PYTHON_VERSION=3.7.5
-ARG PYINSTALLER_VERSION=3.6
+ARG PYTHON_VERSION=3.9.6
+ARG PYINSTALLER_VERSION=4.2
 
 # we need wine for this all to work, so we'll use the PPA
 RUN set -x \
     && dpkg --add-architecture i386 \
     && apt-get update -qy \
-    && apt-get install --no-install-recommends -qfy apt-transport-https software-properties-common wget \
+    && apt-get install --no-install-recommends -qfy apt-transport-https software-properties-common wget xvfb xdotool x11-utils xterm gpg-agent rename \
     && wget -nv https://dl.winehq.org/wine-builds/winehq.key \
     && apt-key add winehq.key \
     && add-apt-repository 'https://dl.winehq.org/wine-builds/ubuntu/' \
@@ -26,6 +26,12 @@ ENV WINEARCH win32
 ENV WINEDEBUG fixme-all
 ENV WINEPREFIX /wine
 
+# xvfb settings
+# from https://github.com/engineervix/docker-pyinstaller/blob/b99163b6eb0a81fc9a0bfd498c09c4e0253d01b2/Dockerfile-py3-win64#L56-L59
+ENV DISPLAY :0
+RUN set -x \
+    && echo 'Xvfb $DISPLAY -screen 0 1024x768x24 &' >> /root/.bashrc
+
 # PYPI repository location
 ENV PYPI_URL=https://pypi.python.org/
 # PYPI index location
@@ -37,17 +43,17 @@ RUN set -x \
     && winetricks win7 \
     && for msifile in `echo core dev exe lib path pip tcltk tools`; do \
         wget -nv "https://www.python.org/ftp/python/$PYTHON_VERSION/win32/${msifile}.msi"; \
-        wine msiexec /i "${msifile}.msi" /qb TARGETDIR=C:/Python37; \
+        wine msiexec /i "${msifile}.msi" /qb TARGETDIR=C:/Python39; \
         rm ${msifile}.msi; \
     done \
-    && cd /wine/drive_c/Python37 \
-    && echo 'wine '\''C:\Python37\python.exe'\'' "$@"' > /usr/bin/python \
-    && echo 'wine '\''C:\Python37\Scripts\easy_install.exe'\'' "$@"' > /usr/bin/easy_install \
-    && echo 'wine '\''C:\Python37\Scripts\pip.exe'\'' "$@"' > /usr/bin/pip \
-    && echo 'wine '\''C:\Python37\Scripts\pyinstaller.exe'\'' "$@"' > /usr/bin/pyinstaller \
-    && echo 'wine '\''C:\Python37\Scripts\pyupdater.exe'\'' "$@"' > /usr/bin/pyupdater \
+    && cd /wine/drive_c/Python39 \
+    && echo 'wine '\''C:\Python39\python.exe'\'' "$@"' > /usr/bin/python \
+    && echo 'wine '\''C:\Python39\Scripts\easy_install.exe'\'' "$@"' > /usr/bin/easy_install \
+    && echo 'wine '\''C:\Python39\Scripts\pip.exe'\'' "$@"' > /usr/bin/pip \
+    && echo 'wine '\''C:\Python39\Scripts\pyinstaller.exe'\'' "$@"' > /usr/bin/pyinstaller \
+    && echo 'wine '\''C:\Python39\Scripts\pyupdater.exe'\'' "$@"' > /usr/bin/pyupdater \
     && echo 'assoc .py=PythonScript' | wine cmd \
-    && echo 'ftype PythonScript=c:\Python37\python.exe "%1" %*' | wine cmd \
+    && echo 'ftype PythonScript=c:\Python39\python.exe "%1" %*' | wine cmd \
     && while pgrep wineserver >/dev/null; do echo "Waiting for wineserver"; sleep 1; done \
     && chmod +x /usr/bin/python /usr/bin/easy_install /usr/bin/pip /usr/bin/pyinstaller /usr/bin/pyupdater \
     && (pip install -U pip || true) \
@@ -61,8 +67,9 @@ ENV W_TMP="$W_DRIVE_C/windows/temp/_$0"
 # install Microsoft Visual C++ Redistributable for Visual Studio 2017 dll files
 RUN set -x \
     && rm -f "$W_TMP"/* \
-    && wget -P "$W_TMP" https://download.visualstudio.microsoft.com/download/pr/11687613/88b50ce70017bf10f2d56d60fcba6ab1/VC_redist.x86.exe \
-    && cabextract -q --directory="$W_TMP" "$W_TMP"/VC_redist.x86.exe \
+    && wget -P "$W_TMP" https://aka.ms/vs/16/release/vc_redist.x86.exe \
+    # https://download.visualstudio.microsoft.com/download/pr/221ed2ae-1269-497b-a962-e113045001fa/1ACD8D5EA1CDC3EB2EB4C87BE3AB28722D0825C15449E5C9CEEF95D897DE52FA/VC_redist.x86.exe
+    && cabextract -q --directory="$W_TMP" "$W_TMP"/vc_redist.x86.exe \
     && cabextract -q --directory="$W_TMP" "$W_TMP/a10" \
     && cabextract -q --directory="$W_TMP" "$W_TMP/a11" \
     && cd "$W_TMP" \
diff --git a/Dockerfile-py3-win64 b/Dockerfile-py3-win64
index e98284e..074f5a4 100644
--- a/Dockerfile-py3-win64
+++ b/Dockerfile-py3-win64
@@ -1,16 +1,16 @@
-FROM ubuntu:16.04
+FROM ubuntu:20.04
 
 ENV DEBIAN_FRONTEND noninteractive
 
 ARG WINE_VERSION=winehq-staging
-ARG PYTHON_VERSION=3.7.5
-ARG PYINSTALLER_VERSION=3.6
+ARG PYTHON_VERSION=3.9.6
+ARG PYINSTALLER_VERSION=4.2
 
 # we need wine for this all to work, so we'll use the PPA
 RUN set -x \
     && dpkg --add-architecture i386 \
     && apt-get update -qy \
-    && apt-get install --no-install-recommends -qfy apt-transport-https software-properties-common wget \
+    && apt-get install --no-install-recommends -qfy apt-transport-https software-properties-common wget xvfb xdotool x11-utils xterm gpg-agent rename \
     && wget -nv https://dl.winehq.org/wine-builds/winehq.key \
     && apt-key add winehq.key \
     && add-apt-repository 'https://dl.winehq.org/wine-builds/ubuntu/' \
@@ -26,6 +26,12 @@ ENV WINEARCH win64
 ENV WINEDEBUG fixme-all
 ENV WINEPREFIX /wine
 
+# xvfb settings
+# from https://github.com/engineervix/docker-pyinstaller/blob/b99163b6eb0a81fc9a0bfd498c09c4e0253d01b2/Dockerfile-py3-win64#L56-L59
+ENV DISPLAY :0
+RUN set -x \
+    && echo 'Xvfb $DISPLAY -screen 0 1024x768x24 &' >> /root/.bashrc
+
 # PYPI repository location
 ENV PYPI_URL=https://pypi.python.org/
 # PYPI index location
@@ -37,17 +43,17 @@ RUN set -x \
     && winetricks win7 \
     && for msifile in `echo core dev exe lib path pip tcltk tools`; do \
         wget -nv "https://www.python.org/ftp/python/$PYTHON_VERSION/amd64/${msifile}.msi"; \
-        wine msiexec /i "${msifile}.msi" /qb TARGETDIR=C:/Python37; \
+        wine msiexec /i "${msifile}.msi" /qb TARGETDIR=C:/Python39; \
         rm ${msifile}.msi; \
     done \
-    && cd /wine/drive_c/Python37 \
-    && echo 'wine '\''C:\Python37\python.exe'\'' "$@"' > /usr/bin/python \
-    && echo 'wine '\''C:\Python37\Scripts\easy_install.exe'\'' "$@"' > /usr/bin/easy_install \
-    && echo 'wine '\''C:\Python37\Scripts\pip.exe'\'' "$@"' > /usr/bin/pip \
-    && echo 'wine '\''C:\Python37\Scripts\pyinstaller.exe'\'' "$@"' > /usr/bin/pyinstaller \
-    && echo 'wine '\''C:\Python37\Scripts\pyupdater.exe'\'' "$@"' > /usr/bin/pyupdater \
+    && cd /wine/drive_c/Python39 \
+    && echo 'wine '\''C:\Python39\python.exe'\'' "$@"' > /usr/bin/python \
+    && echo 'wine '\''C:\Python39\Scripts\easy_install.exe'\'' "$@"' > /usr/bin/easy_install \
+    && echo 'wine '\''C:\Python39\Scripts\pip.exe'\'' "$@"' > /usr/bin/pip \
+    && echo 'wine '\''C:\Python39\Scripts\pyinstaller.exe'\'' "$@"' > /usr/bin/pyinstaller \
+    && echo 'wine '\''C:\Python39\Scripts\pyupdater.exe'\'' "$@"' > /usr/bin/pyupdater \
     && echo 'assoc .py=PythonScript' | wine cmd \
-    && echo 'ftype PythonScript=c:\Python37\python.exe "%1" %*' | wine cmd \
+    && echo 'ftype PythonScript=c:\Python39\python.exe "%1" %*' | wine cmd \
     && while pgrep wineserver >/dev/null; do echo "Waiting for wineserver"; sleep 1; done \
     && chmod +x /usr/bin/python /usr/bin/easy_install /usr/bin/pip /usr/bin/pyinstaller /usr/bin/pyupdater \
     && (pip install -U pip || true) \
@@ -61,10 +67,13 @@ ENV W_TMP="$W_DRIVE_C/windows/temp/_$0"
 # install Microsoft Visual C++ Redistributable for Visual Studio 2017 dll files
 RUN set -x \
     && rm -f "$W_TMP"/* \
-    && wget -P "$W_TMP" https://download.visualstudio.microsoft.com/download/pr/11100230/15ccb3f02745c7b206ad10373cbca89b/VC_redist.x64.exe \
-    && cabextract -q --directory="$W_TMP" "$W_TMP"/VC_redist.x64.exe \
-    && cabextract -q --directory="$W_TMP" "$W_TMP/a10" \
+    && wget -P "$W_TMP" https://aka.ms/vs/16/release/vc_redist.x64.exe \
+    # https://download.visualstudio.microsoft.com/download/pr/36e45907-8554-4390-ba70-9f6306924167/97CC5066EB3C7246CF89B735AE0F5A5304A7EE33DC087D65D9DFF3A1A73FE803/VC_redist.x64.exe
+    && ls "$W_TMP"/ \
+    && cabextract -q --directory="$W_TMP" "$W_TMP"/vc_redist.x64.exe \
     && cabextract -q --directory="$W_TMP" "$W_TMP/a11" \
+    && cabextract -q --directory="$W_TMP" "$W_TMP/a12" \
+    && cabextract -q --directory="$W_TMP" "$W_TMP/a13" \
     && cd "$W_TMP" \
     && rename 's/_/\-/g' *.dll \
     && cp "$W_TMP"/*.dll "$W_SYSTEM64_DLLS"/