diff --git a/services/tunnelbroker/docker/install_cryptopp.sh b/services/tunnelbroker/docker/install_cryptopp.sh
--- a/services/tunnelbroker/docker/install_cryptopp.sh
+++ b/services/tunnelbroker/docker/install_cryptopp.sh
@@ -6,8 +6,7 @@
 git clone --recurse-submodules -b CRYPTOPP_8_6_0 --single-branch https://github.com/weidai11/cryptopp
 pushd cryptopp
 mkdir build
-CXXFLAGS="-DNDEBUG -g2 -O3 -std=c++11"
-make
+make CXXFLAGS="-DNDEBUG -g2 -O3 -std=c++11"
 make libcryptopp.pc
 make install