diff --git a/build.py b/build.py
index 64e5b04473..fbb28d86ac 100755
--- a/build.py
+++ b/build.py
@@ -215,8 +215,9 @@ def build_ol_whitespace_js(t):
 virtual('build-all', 'build/ol-all.js')
 
 
-@target('build/ol-all.js', PLOVR_JAR, SRC, INTERNAL_SRC, SHADER_SRC,
-        LIBTESS_JS_SRC, 'buildcfg/base.json', 'buildcfg/ol-all.json')
+@target('build/ol-all.js', PLOVR_JAR, SRC, EXTERNAL_SRC, INTERNAL_SRC,
+        SHADER_SRC, LIBTESS_JS_SRC, 'buildcfg/base.json',
+        'buildcfg/ol-all.json')
 def build_ol_all_js(t):
     t.output('%(JAVA)s', '-server', '-XX:+TieredCompilation', '-jar',
             PLOVR_JAR, 'build', 'buildcfg/ol-all.json')