diff --git a/Dockerfile.n8n b/Dockerfile.n8n
index b8c58ba..035c2ff 100644
--- a/Dockerfile.n8n
+++ b/Dockerfile.n8n
@@ -5,6 +5,7 @@ ARG NODE_ENV=production
 ARG N8N_PORT=5678
 ARG SHOWDOWN_VERSION=^2.1.0
 ARG SLACKIFY_MARKDOWN_VERSION=^4.5.0
+ARG PDF_LIB_VERSION=1.17.1
 
 # Install git for backup script and other packages + install external packages in one layer
 USER root
@@ -13,12 +14,13 @@ RUN set -eux; \
   npm install -g --no-audit --no-fund --ignore-scripts \
     --legacy-peer-deps --no-workspaces \
     --unsafe-perm \
+    pdf-lib@${PDF_LIB_VERSION} \
     showdown@${SHOWDOWN_VERSION} \
     slackify-markdown@${SLACKIFY_MARKDOWN_VERSION} && \
   npm cache clean --force
 
 # Configure external modules allowlist used by Code/Function nodes
-ENV NODE_FUNCTION_ALLOW_EXTERNAL="showdown,slackify-markdown"
+ENV NODE_FUNCTION_ALLOW_EXTERNAL="showdown,slackify-markdown,pdf-lib"
 
 # Create app directory
 WORKDIR /home/node