diff --git a/pyodide/build_pyodide.sh b/pyodide/build_pyodide.sh
index db5c5f08b0..205ee5395f 100755
--- a/pyodide/build_pyodide.sh
+++ b/pyodide/build_pyodide.sh
@@ -1,6 +1,9 @@
 #!/usr/bin/bash
 set -ex
 
+PYODIDE_VERSION=0.29.3
+PYODIDE_BUILD_VERSION=0.33.0
+
 # Script is assuming that it will be possible to execute it multiple times
 # therefore we're clearing venv each time and ignoring existing 'emsdk' folder.
 
@@ -11,13 +14,14 @@ source .venv/bin/activate
 
 # Install pyodide cross build environment.
 # Instructions: https://pyodide.org/en/stable/development/building-packages.html
-uv pip install pyodide-build
+uv pip install "pyodide-build==${PYODIDE_BUILD_VERSION}"
 # `uv run` is required, so xbuildenv would skip using `pip`.
-uv run pyodide xbuildenv install
+uv run pyodide xbuildenv install "${PYODIDE_VERSION}"
 uv run pyodide xbuildenv install-emscripten
 
 EMSDK_ROOT=$(pyodide config get emscripten_dir)
-source ${EMSDK_ROOT}/emsdk_env.sh
+[ -f "${EMSDK_ROOT}/emsdk_env.sh" ] && source "${EMSDK_ROOT}/emsdk_env.sh"
+[ -f "${EMSDK_ROOT}/../../emsdk_env.sh" ] && source "${EMSDK_ROOT}/../../emsdk_env.sh"
 which emcc
 
 mkdir -p packages/ifcopenshell