diff --git a/scripts/setup_ros2_desktop.sh b/scripts/setup_ros2_desktop.sh
index 529c37c..31b49e1 100755
--- a/scripts/setup_ros2_desktop.sh
+++ b/scripts/setup_ros2_desktop.sh
@@ -68,9 +68,13 @@ if ! sudo grep -qs 'break-system-packages' /root/.config/pip/pip.conf 2>/dev/nul
 fi
 # rosdep calls `pip install -U <pkg>` which upgrades every transitive dependency,
 # including packages installed by apt that have no pip RECORD file, causing an
-# uninstall failure. Pre-installing fastmcp with --ignore-installed creates pip
-# RECORD files for all its transitive deps so the later rosdep upgrade succeeds.
-sudo pip3 install --break-system-packages --ignore-installed fastmcp
+# uninstall failure. Pre-installing these packages with --ignore-installed creates
+# pip RECORD files for all their transitive deps so the later rosdep upgrade succeeds.
+# fastapi>=0.100.0 + starlette>=0.27.0 are pinned together to avoid the
+# "Router.__init__() got an unexpected keyword argument 'on_startup'" error that
+# occurs when the apt-installed fastapi (old) is mixed with a newer pip starlette.
+sudo pip3 install --break-system-packages --ignore-installed \
+    "fastapi>=0.100.0" "starlette>=0.27.0" fastmcp
 
 PROGRESS 100 "Done"
 echo "ROS2 Jazzy Desktop installed successfully."
diff --git a/scripts/setup_ros2_ros_base.sh b/scripts/setup_ros2_ros_base.sh
index d958cc6..4b25922 100755
--- a/scripts/setup_ros2_ros_base.sh
+++ b/scripts/setup_ros2_ros_base.sh
@@ -68,9 +68,13 @@ if ! sudo grep -qs 'break-system-packages' /root/.config/pip/pip.conf 2>/dev/nul
 fi
 # rosdep calls `pip install -U <pkg>` which upgrades every transitive dependency,
 # including packages installed by apt that have no pip RECORD file, causing an
-# uninstall failure. Pre-installing fastmcp with --ignore-installed creates pip
-# RECORD files for all its transitive deps so the later rosdep upgrade succeeds.
-sudo pip3 install --break-system-packages --ignore-installed fastmcp
+# uninstall failure. Pre-installing these packages with --ignore-installed creates
+# pip RECORD files for all their transitive deps so the later rosdep upgrade succeeds.
+# fastapi>=0.100.0 + starlette>=0.27.0 are pinned together to avoid the
+# "Router.__init__() got an unexpected keyword argument 'on_startup'" error that
+# occurs when the apt-installed fastapi (old) is mixed with a newer pip starlette.
+sudo pip3 install --break-system-packages --ignore-installed \
+    "fastapi>=0.100.0" "starlette>=0.27.0" fastmcp
 
 PROGRESS 100 "Done"
 echo "ROS2 Jazzy (ros-base) installed successfully."
diff --git a/src/iiwa_web/setup.py b/src/iiwa_web/setup.py
index b288152..3db5655 100644
--- a/src/iiwa_web/setup.py
+++ b/src/iiwa_web/setup.py
@@ -13,7 +13,8 @@ setup(
     ],
     install_requires=[
         'setuptools',
-        'fastapi',
+        'fastapi>=0.100.0',
+        'starlette>=0.27.0',
         'uvicorn[standard]',
         'python-multipart',
         'fastmcp',