diff --git a/external/dist/README.md b/external/dist/README.md
new file mode 100644
index 000000000..daef282c1
--- /dev/null
+++ b/external/dist/README.md
@@ -0,0 +1,10 @@
+# PDF.js
+
+PDF.js is a Portable Document Format (PDF) library that is built with HTML5.
+Our goal is to create a general-purpose, web standards-based platform for
+parsing and rendering PDFs.
+
+This is a pre-built version of the PDF.js source code. It is automatically
+generated by the build scripts.
+
+See https://github.com/mozilla/pdf.js for learning and contributing.
diff --git a/make.js b/make.js
index de62cc5ff..e257c11a9 100644
--- a/make.js
+++ b/make.js
@@ -246,6 +246,7 @@ target.dist = function() {
   echo('### Overwriting all files');
   rm('-rf', DIST_DIR + '*');
 
+  cp('-R', ROOT_DIR + 'external/dist/*', DIST_DIR);
   cp('-R', GENERIC_DIR + 'LICENSE', DIST_DIR);
   cp('-R', GENERIC_DIR + 'web/cmaps', DIST_DIR);
   mkdir('-p', DIST_DIR + 'build/');