diff --git a/_SwiftPackageManagerFile.cpp b/_SwiftPackageManagerFile.cpp
new file mode 100755
index 000000000..52729cfe9
--- /dev/null
+++ b/_SwiftPackageManagerFile.cpp
@@ -0,0 +1,5 @@
+// This file exists only to trigger the json module to build; without
+// it swiftpm won't build anything, and then the package is not available for
+// the modules that need it.
+
+#include <json.hpp>