diff --git a/scripts/build-rust-native-library.sh b/scripts/build-rust-native-library.sh
--- a/scripts/build-rust-native-library.sh
+++ b/scripts/build-rust-native-library.sh
@@ -25,7 +25,7 @@
 
 # Set C++ standard and build cxx bridge
 export CXXFLAGS="-std=c++14"
-env PATH="${build_path}" cargo build
+env PATH="${build_path}" cargo build --release
 # Build universal static library (works on simulator and iOS)
 env PATH="${build_path}" cargo lipo --release
 # Unset the flag specifying C++ standard
diff --git a/services/tunnelbroker/Dockerfile b/services/tunnelbroker/Dockerfile
--- a/services/tunnelbroker/Dockerfile
+++ b/services/tunnelbroker/Dockerfile
@@ -37,7 +37,7 @@
 
 # Build Rust by Cargo
 WORKDIR /transferred/services/tunnelbroker
-RUN cargo build
+RUN cargo build --release
 
 CMD if [ "$COMM_TEST_SERVICES" -eq 1 ];\
   then\