diff --git a/dotnet-vnc/Dockerfile b/dotnet-vnc/Dockerfile
index b8dbf3212..570332e1c 100644
--- a/dotnet-vnc/Dockerfile
+++ b/dotnet-vnc/Dockerfile
@@ -1,14 +1,18 @@
 FROM gitpod/workspace-full-vnc:latest
 
-USER root
-RUN wget -q https://packages.microsoft.com/config/ubuntu/20.04/packages-microsoft-prod.deb && \
-    dpkg -i packages-microsoft-prod.deb && \
-    rm -rf packages-microsoft-prod.deb && \
-    add-apt-repository universe && \
-    apt-get update && \
-    echo resolvconf resolvconf/linkify-resolvconf boolean false | debconf-set-selections && \
-    DEBIAN_FRONTEND=noninteractive ACCEPT_EULA=Y apt-get -y -o APT::Install-Suggests="true" install \
-        dotnet-sdk-3.1 \
-        fsharp \
-        mono-complete && \
-    rm -rf /var/lib/apt/lists/*
+USER gitpod
+
+# Install .NET Core 3.1 SDK binaries on Ubuntu 20.04
+# Source: https://dev.to/carlos487/installing-dotnet-core-in-ubuntu-20-04-6jh
+RUN mkdir -p /home/gitpod/dotnet && curl -fsSL https://download.visualstudio.microsoft.com/download/pr/f65a8eb0-4537-4e69-8ff3-1a80a80d9341/cc0ca9ff8b9634f3d9780ec5915c1c66/dotnet-sdk-3.1.201-linux-x64.tar.gz | tar xz -C /home/gitpod/dotnet
+ENV DOTNET_ROOT=/home/gitpod/dotnet
+ENV PATH=$PATH:/home/gitpod/dotnet
+
+# Install F# with Mono
+RUN sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF \
+ && echo "deb https://download.mono-project.com/repo/ubuntu stable-focal main" | sudo tee /etc/apt/sources.list.d/mono-official-stable.list \
+ && sudo apt-get update \
+ && sudo apt-get install -y \
+    mono-complete \
+    fsharp \
+ && sudo rm -rf /var/lib/apt/lists/*
diff --git a/dotnet/Dockerfile b/dotnet/Dockerfile
index b36f5a1d8..da37ccff3 100644
--- a/dotnet/Dockerfile
+++ b/dotnet/Dockerfile
@@ -1,14 +1,18 @@
 FROM gitpod/workspace-full:latest
 
-USER root
-RUN wget -q https://packages.microsoft.com/config/ubuntu/20.04/packages-microsoft-prod.deb && \
-    dpkg -i packages-microsoft-prod.deb && \
-    rm -rf packages-microsoft-prod.deb && \
-    add-apt-repository universe && \
-    apt-get update && \
-    echo resolvconf resolvconf/linkify-resolvconf boolean false | debconf-set-selections && \
-    DEBIAN_FRONTEND=noninteractive ACCEPT_EULA=Y apt-get -y -o APT::Install-Suggests="true" install \
-        dotnet-sdk-3.1 \
-        fsharp \
-        mono-complete && \
-    rm -rf /var/lib/apt/lists/*
+USER gitpod
+
+# Install .NET Core 3.1 SDK binaries on Ubuntu 20.04
+# Source: https://dev.to/carlos487/installing-dotnet-core-in-ubuntu-20-04-6jh
+RUN mkdir -p /home/gitpod/dotnet && curl -fsSL https://download.visualstudio.microsoft.com/download/pr/f65a8eb0-4537-4e69-8ff3-1a80a80d9341/cc0ca9ff8b9634f3d9780ec5915c1c66/dotnet-sdk-3.1.201-linux-x64.tar.gz | tar xz -C /home/gitpod/dotnet
+ENV DOTNET_ROOT=/home/gitpod/dotnet
+ENV PATH=$PATH:/home/gitpod/dotnet
+
+# Install F# with Mono
+RUN sudo apt-key adv --keyserver hkp://keyserver.ubuntu.com:80 --recv-keys 3FA7E0328081BFF6A14DA29AA6A19B38D3D831EF \
+ && echo "deb https://download.mono-project.com/repo/ubuntu stable-focal main" | sudo tee /etc/apt/sources.list.d/mono-official-stable.list \
+ && sudo apt-get update \
+ && sudo apt-get install -y \
+    mono-complete \
+    fsharp \
+ && sudo rm -rf /var/lib/apt/lists/*