diff --git a/backend/Dockerfile b/backend/Dockerfile
index b3517f2..6e9094f 100644
--- a/backend/Dockerfile
+++ b/backend/Dockerfile
@@ -17,8 +17,10 @@ COPY prisma ./prisma/
 # Install dependencies
 RUN npm install
 
-# Build tinypdf-plus package
-RUN cd node_modules/tinypdf-plus && /root/.bun/bin/bun run build || (echo "tinypdf-plus build failed" && exit 1)
+# Build tinypdf-plus package (add bun to PATH)
+RUN cd node_modules/tinypdf-plus && \
+    PATH=/root/.bun/bin:$PATH /root/.bun/bin/bun run build || \
+    (echo "tinypdf-plus build failed" && exit 1)
 
 # Copy source
 COPY . .