diff --git a/scripts/install-dev.sh b/scripts/install-dev.sh
index c4359f63..cff957e8 100755
--- a/scripts/install-dev.sh
+++ b/scripts/install-dev.sh
@@ -4,6 +4,27 @@ set -euo pipefail
 ROOT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")/.." && pwd)"
 cd "$ROOT_DIR"
 
-python3 -m venv .venv
+# skill-manager requires Python 3.11+. The bare `python3` on a machine may be
+# older (e.g. 3.9), which silently resolves incompatible dependency versions,
+# so pick the first interpreter that satisfies the minimum.
+find_python() {
+  for candidate in python3.14 python3.13 python3.12 python3.11 python3; do
+    if command -v "$candidate" >/dev/null 2>&1 \
+      && "$candidate" -c 'import sys; sys.exit(0 if sys.version_info >= (3, 11) else 1)'; then
+      echo "$candidate"
+      return 0
+    fi
+  done
+  return 1
+}
+
+PYTHON="$(find_python)" || {
+  echo "error: Python 3.11+ is required but was not found on PATH." >&2
+  exit 1
+}
+echo "Using $("$PYTHON" --version) ($PYTHON)"
+
+"$PYTHON" -m venv .venv
+"$ROOT_DIR/.venv/bin/python" -m pip install --upgrade pip
 "$ROOT_DIR/.venv/bin/pip" install -r requirements.txt
 npm install