diff --git a/.readthedocs.yaml b/.readthedocs.yaml
index 0090fafe..a33ac0eb 100644
--- a/.readthedocs.yaml
+++ b/.readthedocs.yaml
@@ -1,6 +1,6 @@
 # kas - setup tool for bitbake based projects
 #
-# Copyright (c) Siemens AG, 2021
+# Copyright (c) Siemens AG, 2021-2024
 #
 # Permission is hereby granted, free of charge, to any person obtaining a copy
 # of this software and associated documentation files (the "Software"), to deal
@@ -23,11 +23,16 @@
 version: 2
 
 build:
-  os: ubuntu-20.04
+  os: ubuntu-24.04
   tools:
-    python: "3.9"
+    python: "3.12"
   apt_packages:
     - python3-newt
+    - make
+    - podman
+  jobs:
+    pre_build:
+      - cd docs && make kas-container-usage && cd ..
 
 python:
   install:
diff --git a/docs/command-line/environment-variables.inc b/docs/command-line/environment-variables.inc
index 09174629..bb33b6ec 100644
--- a/docs/command-line/environment-variables.inc
+++ b/docs/command-line/environment-variables.inc
@@ -166,6 +166,13 @@ Variables Glossary
 | ``PARALLEL_MAKE``        |                                                  |
 | (C,K,E)                  |                                                  |
 +--------------------------+--------------------------------------------------+
+| ``BUILDTOOLS_DIR`` (K)   | The path to the directory where buildtools have  |
+|                          | been installed. The environment-setup script     |
+|                          | will run before bitbake, so the whole buildtools |
+|                          | environment will be available. More information  |
+|                          | on how to install or generate buildtools can be  |
+|                          | found at: |yp_doc_buildtools|                    |
++--------------------------+--------------------------------------------------+
 
 .. |aws_cred| replace:: ``AWS_ROLE_ARN``
                         ``AWS_SHARED_CREDENTIALS_FILE``
@@ -177,6 +184,7 @@ Variables Glossary
                               ``CI_SERVER_SHELL_SSH_HOST``
                               ``CI_SERVER_SHELL_SSH_PORT``
 
+.. |yp_doc_buildtools| replace:: https://docs.yoctoproject.org/3.3/ref-manual/system-requirements.html#required-git-tar-python-and-gcc-versions
 .. only:: html
 
     For details about the access of remote resources, see
diff --git a/kas/libkas.py b/kas/libkas.py
index a8a6c423..73391aad 100644
--- a/kas/libkas.py
+++ b/kas/libkas.py
@@ -33,6 +33,7 @@
 import errno
 import pathlib
 import signal
+import glob
 from subprocess import Popen, PIPE
 from .context import get_context
 from .kasusererror import KasUserError, CommandExecError
@@ -252,9 +253,16 @@ def get_build_environ(build_system):
     if not init_repo:
         raise InitBuildEnvError('Did not find any init-build-env script')
 
+    buildtools_env =""
+    if "BUILDTOOLS_DIR" in os.environ:
+       envfiles = glob.glob(os.path.join(os.environ["BUILDTOOLS_DIR"],"environment-setup-*"))
+       if len(envfiles) == 1:
+          buildtools_env = "source {}\n".format(os.path.realpath(envfiles[0]))
+
     with tempfile.TemporaryDirectory() as temp_dir:
         script = f"""#!/bin/bash
         set -e
+        {buildtools_env}
         source {init_script} $1 > /dev/null
         env
         """