diff --git a/tests/unit/libexpr-support/local.mk b/tests/unit/libexpr-support/local.mk
index 28e87b8f2..12a76206a 100644
--- a/tests/unit/libexpr-support/local.mk
+++ b/tests/unit/libexpr-support/local.mk
@@ -20,4 +20,4 @@ libexpr-test-support_LIBS = \
     libstore-test-support libutil-test-support \
     libexpr libstore libutil
 
-libexpr-test-support_LDFLAGS := -lrapidcheck
+libexpr-test-support_LDFLAGS := -pthread -lrapidcheck
diff --git a/tests/unit/libstore-support/local.mk b/tests/unit/libstore-support/local.mk
index d5d657c91..ff075c96a 100644
--- a/tests/unit/libstore-support/local.mk
+++ b/tests/unit/libstore-support/local.mk
@@ -18,4 +18,4 @@ libstore-test-support_LIBS = \
     libutil-test-support \
     libstore libutil
 
-libstore-test-support_LDFLAGS := -lrapidcheck
+libstore-test-support_LDFLAGS := -pthread -lrapidcheck
diff --git a/tests/unit/libutil-support/local.mk b/tests/unit/libutil-support/local.mk
index 43a1551e5..2ee2cdb6c 100644
--- a/tests/unit/libutil-support/local.mk
+++ b/tests/unit/libutil-support/local.mk
@@ -16,4 +16,4 @@ libutil-test-support_CXXFLAGS += $(libutil-tests_EXTRA_INCLUDES)
 
 libutil-test-support_LIBS = libutil
 
-libutil-test-support_LDFLAGS := -lrapidcheck
+libutil-test-support_LDFLAGS := -pthread -lrapidcheck