diff --git a/.devcontainer/humble/Dockerfile b/.devcontainer/humble/Dockerfile
index 2c5b6b4..a71f968 100644
--- a/.devcontainer/humble/Dockerfile
+++ b/.devcontainer/humble/Dockerfile
@@ -14,7 +14,6 @@ RUN apt-get update && apt-get upgrade -y \
     && apt-get install -y \
     sudo \
     git \
-    doxygen \
     && echo $USERNAME ALL=\(root\) NOPASSWD:ALL > /etc/sudoers.d/$USERNAME \
     && chmod 0440 /etc/sudoers.d/$USERNAME
 
diff --git a/.devcontainer/jazzy/Dockerfile b/.devcontainer/jazzy/Dockerfile
index 72a2198..97163cc 100644
--- a/.devcontainer/jazzy/Dockerfile
+++ b/.devcontainer/jazzy/Dockerfile
@@ -14,7 +14,6 @@ RUN apt-get update && apt-get upgrade -y \
     && apt-get install -y \
     sudo \
     git \
-    doxygen \
     && echo $USERNAME ALL=\(root\) NOPASSWD:ALL > /etc/sudoers.d/$USERNAME \
     && chmod 0440 /etc/sudoers.d/$USERNAME
 
diff --git a/docs/readme.md b/docs/readme.md
index 11c1b2b..3013202 100644
--- a/docs/readme.md
+++ b/docs/readme.md
@@ -3,6 +3,9 @@
 The documentation site is generated with Doxygen from the existing Markdown in this `docs/` tree together with comments from the source code. The Doxygen configuration lives at the repository root in [`Doxygen`](../Doxygen).
 
 ```bash
+# install doxygen if it is not already available
+sudo apt-get update && sudo apt-get install -y doxygen
+
 # from the repository root
 doxygen Doxygen
 ```