diff --git a/atlas.json b/atlas.json
index 4f2fbd85..03ae8f1c 100644
--- a/atlas.json
+++ b/atlas.json
@@ -3,7 +3,8 @@
   "files": [
     "ch01.asciidoc",
     "ch02.asciidoc",
-    "ch03.asciidoc"
+    "ch03.asciidoc",
+    "ch04.asciidoc"
   ],
   "formats": {
     "pdf": {