diff --git a/.gitignore b/.gitignore
index 34eb815..a47de13 100755
--- a/.gitignore
+++ b/.gitignore
@@ -4,6 +4,11 @@ dist-showcase/
 dist-demo/
 *.log
 .DS_Store
+
+# Generated by scripts/build_demo_pdf.py — the rendered demo PDF and the
+# intermediate page PNGs it rasterizes on the way there (~2 MB).
+output/
+tmp/
 # impeccable-ignore-start
 .impeccable/config.local.json
 .impeccable/hook.cache.json