diff --git a/contrib/teamcity/build.sh b/contrib/teamcity/build.sh
index 12b8f5fa8..d38c26da4 100755
--- a/contrib/teamcity/build.sh
+++ b/contrib/teamcity/build.sh
@@ -1,75 +1,76 @@
 #!/bin/bash
 
 set -eu
 
 TOPLEVEL=`git rev-parse --show-toplevel`
 if [[ -z "${TOPLEVEL}" ]]; then
 	echo "No .git directory found, assuming pwd"
 	TOPLEVEL=`pwd -P`
 fi
 
 BUILD_DIR="${TOPLEVEL}/build"
 mkdir -p ${BUILD_DIR}
 
 ## Generate necessary autoconf files
 cd ${TOPLEVEL}
 ./autogen.sh
 cd ${BUILD_DIR}
 
 rm -f build.status test_bitcoin.xml
 
 ## Determine the number of build threads
 THREADS=$(nproc || sysctl -n hw.ncpu)
 
 # Default to nothing
 : ${DISABLE_WALLET:=}
+: ${CONFIGURE_FLAGS:=}
 
-CONFIGURE_FLAGS=("--prefix=`pwd`")
+CONFIGURE_FLAGS+=("--prefix=`pwd`")
 if [[ ! -z "${DISABLE_WALLET}" ]]; then
 	echo "*** Building without wallet"
 	CONFIGURE_FLAGS+=("--disable-wallet")
 fi
 
 # Default to nothing
 : ${ENABLE_DEBUG:=}
 
 if [[ ! -z "${ENABLE_DEBUG}" ]]; then
 	echo "*** Building with debug"
 	CONFIGURE_FLAGS+=("--enable-debug")
 fi
 
 ../configure "${CONFIGURE_FLAGS[@]}"
 
 # Run build
 make -j ${THREADS}
 
 # Default to nothing
 : ${DISABLE_TESTS:=}
 
 # If DISABLE_TESTS is unset (default), run the tests
 if [[ -z "${DISABLE_TESTS}" ]]; then
 	echo "*** Running tests"
 
 	# Run unit tests
 	make -j ${THREADS} check
 
 	# FIXME Remove when the functional tests are running with debug enabled
 	if [[ -z "${ENABLE_DEBUG}" ]]; then
 		mkdir -p output/
 		BRANCH=$(git rev-parse --abbrev-ref HEAD)
 		if [[ ! -z "${DISABLE_WALLET}" ]]; then
 			echo "Skipping rpc testing due to disabled wallet functionality."
 		elif [[ "${BRANCH}" == "master" ]]; then
 			./test/functional/test_runner.py --cutoff=600 --tmpdirprefix=output
 			./test/functional/test_runner.py --cutoff=600 --tmpdirprefix=output --with-gravitonactivation
 		else
 			./test/functional/test_runner.py --tmpdirprefix=output
 			./test/functional/test_runner.py --tmpdirprefix=output --with-gravitonactivation
 		fi
 	else
 		echo "*** Functional tests have been skipped"
 	fi
 else
 	echo "*** Tests have been skipped"
 fi