diff --git a/docker/tna-python-dev/Dockerfile b/docker/tna-python-dev/Dockerfile
index 4f5337b..e4ad4cd 100644
--- a/docker/tna-python-dev/Dockerfile
+++ b/docker/tna-python-dev/Dockerfile
@@ -50,7 +50,7 @@ COPY --chown=app lib/* /home/app/
 # fixing both Python and JS/CSS code
 # ==========================================
 RUN python -m pip install --no-cache-dir --quiet black==24.10.0 flake8==7.1.1 isort==5.13.2; \
-    . "$HOME/.nvm/nvm.sh"; \
+    source "$HOME/.nvm/nvm.sh"; \
     npm install -g prettier@3.4.2 eslint@8.56.0 stylelint@16.11.0 stylelint-config-standard-scss@14.0.0 stylelint-selector-bem-pattern@4.0.1
 
 CMD ["dev"]