diff --git a/cpp/Makefile b/cpp/Makefile
index 120aa577b78eb9f21a2335caa6508c465fd6bb03..a1c8f513fb29425116eb8aa2c5b159a61e887bad 100644
--- a/cpp/Makefile
+++ b/cpp/Makefile
@@ -15,6 +15,7 @@ TARGETS += switchchain_dsp
 TARGETS += switchchain_exponent
 TARGETS += switchchain_initialtris
 TARGETS += switchchain_mixingtime
+TARGETS += switchchain_spectrum
 TARGETS += switchchain_successrates
 TARGETS += switchchain_timeevol