diff --git a/tests/host/Makefile b/tests/host/Makefile
index 38393f824..17007f444 100644
--- a/tests/host/Makefile
+++ b/tests/host/Makefile
@@ -63,6 +63,7 @@ CORE_CPP_FILES := $(addprefix $(CORE_PATH)/,\
 	spiffs/spiffs_hydrogen.cpp \
 	spiffs/spiffs_nucleus.cpp \
 	libb64/cencode.cpp \
+	libb64/cdecode.cpp \
 	Schedule.cpp \
 )