diff --git a/CMakeLists.txt b/CMakeLists.txt
index aed24a68d..20bbc2c95 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -24,6 +24,7 @@ find_package(SwiftPM QUIET)
 find_package(LLBuild QUIET)
 find_package(ArgumentParser CONFIG REQUIRED)
 find_package(SwiftCollections QUIET)
+find_package(SwiftSystem CONFIG REQUIRED)
 
 include(SwiftSupport)