diff --git a/services/tunnelbroker/docker/install_cryptopp.sh b/services/tunnelbroker/docker/install_cryptopp.sh
index 7554897c7..1cbb003e6 100755
--- a/services/tunnelbroker/docker/install_cryptopp.sh
+++ b/services/tunnelbroker/docker/install_cryptopp.sh
@@ -1,15 +1,14 @@
 #!/usr/bin/env bash
 set -e
 
 cd /tmp
 
 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
 
 popd # cryptopp
 rm -rf cryptopp