diff --git a/build.json b/build.json
index 868e56a1..86d11c1d 100644
--- a/build.json
+++ b/build.json
@@ -1,7 +1,7 @@
 {
   "variable": {
     "PYTHON_VERSION": {
-      "default": "3.9.13"
+      "default": "3.10.6"
     },
     "AIIDA_VERSION": {
       "default": "2.1.2"
diff --git a/stack/base/Dockerfile b/stack/base/Dockerfile
index 16a84dcf..faff8018 100644
--- a/stack/base/Dockerfile
+++ b/stack/base/Dockerfile
@@ -18,14 +18,11 @@ ARG AIIDA_VERSION
 
 # Install the shared requirements.
 COPY requirements.txt .
-RUN mamba install --yes \
-     aiida-core=${AIIDA_VERSION} \
-     --file requirements.txt \
-     && mamba clean --all -f -y && \
+RUN pip install --no-cache-dir aiida-core==${AIIDA_VERSION} \
+     -r requirements.txt && \
      fix-permissions "${CONDA_DIR}" && \
      fix-permissions "/home/${NB_USER}"
 
-
 # Pin shared requirements in the base environemnt.
 RUN cat requirements.txt | xargs -I{} conda config --system --add pinned_packages {}
 
diff --git a/stack/full-stack/Dockerfile b/stack/full-stack/Dockerfile
index 332454ff..6e9a53fb 100644
--- a/stack/full-stack/Dockerfile
+++ b/stack/full-stack/Dockerfile
@@ -10,7 +10,7 @@ COPY --from=base "${CONDA_DIR}/envs/aiida-core-services" "${CONDA_DIR}/envs/aiid
 COPY --from=base /usr/local/bin/before-notebook.d /usr/local/bin/before-notebook.d
 
 RUN fix-permissions "${CONDA_DIR}"
-RUN fix-permissions "/home/${NB_USER}/.aiida"
+RUN fix-permissions "/home/${NB_USER}"
 
 USER ${NB_USER}
 
diff --git a/stack/lab/Dockerfile b/stack/lab/Dockerfile
index c05801d9..6389d3f6 100644
--- a/stack/lab/Dockerfile
+++ b/stack/lab/Dockerfile
@@ -22,9 +22,7 @@ RUN apt-get update --yes && \
 
 # Install aiidalab package
 ARG AIIDALAB_VERSION
-RUN mamba install --yes \
-     aiidalab=${AIIDALAB_VERSION} \
-     && mamba clean --all -f -y && \
+RUN pip install --no-cache-dir aiidalab==${AIIDALAB_VERSION} && \
      fix-permissions "${CONDA_DIR}" && \
      fix-permissions "/home/${NB_USER}"