diff --git a/src/util/params.cpp b/src/util/params.cpp
index 3edc7d329..d91c08bca 100644
--- a/src/util/params.cpp
+++ b/src/util/params.cpp
@@ -20,7 +20,6 @@ Notes:
 #include "util/rational.h"
 #include "util/symbol.h"
 #include "util/dictionary.h"
-#include <thread>
 #include <atomic>
 
 params_ref params_ref::g_empty_params_ref;