diff --git a/contrib/teamcity/gitian.sh b/contrib/teamcity/gitian.sh
index 348a519a72..31e8e993eb 100755
--- a/contrib/teamcity/gitian.sh
+++ b/contrib/teamcity/gitian.sh
@@ -1,45 +1,50 @@
 #!/usr/bin/env bash
 
 export LC_ALL=C
 
 set -euxo pipefail
 
 cd "$(dirname "$0")"
 
 COMMIT=$(git rev-parse HEAD)
 export COMMIT
 PROJECT_ROOT=$(git rev-parse --show-toplevel)
 export PROJECT_ROOT
 export USE_LXC=1
 export GITIAN_HOST_IP=10.0.3.1
 export LXC_BRIDGE=lxcbr0
 export LXC_GUEST_IP=10.0.3.5
 
 cd ~/gitian-builder
 
 if [[ "${OS_NAME}" == "osx" ]]; then
-  wget https://storage.googleapis.com/f4936e83b2dcbca742be51fb9692b153/MacOSX10.11.sdk.tar.gz
-  echo "4732b52b5ebe300c8c91cbeed6d19d59c1ff9c56c7a1dd6cfa518b9c2c72abde  MacOSX10.11.sdk.tar.gz" | sha256sum -c
+  OSX_SDK="MacOSX10.11.sdk.tar.gz"
+  OSX_SDK_SHA256="4732b52b5ebe300c8c91cbeed6d19d59c1ff9c56c7a1dd6cfa518b9c2c72abde"
   mkdir -p inputs
-  echo "Downloaded"
-  mv MacOSX10.11.sdk.tar.gz inputs
+  pushd inputs
+  if [ ! $(echo "${OSX_SDK_SHA256}  ${OSX_SDK}" | sha256sum -c) ] ; then
+    rm -f "${OSX_SDK}"
+    wget https://storage.googleapis.com/f4936e83b2dcbca742be51fb9692b153/"${OSX_SDK}"
+    echo "${OSX_SDK_SHA256}  ${OSX_SDK}" | sha256sum -c
+  fi
+  popd
 fi
 
 ## Determine the number of build threads
 THREADS=$(nproc || sysctl -n hw.ncpu)
 
 RESULT_DIR="${PROJECT_ROOT}/gitian-results"
 OS_DIR="${RESULT_DIR}/${OS_NAME}"
 mkdir -p "${OS_DIR}"
 
 move_log() {
   mv var/install.log "${RESULT_DIR}/"
   mv var/build.log "${RESULT_DIR}/"
 }
 trap "move_log" ERR
 
 ./bin/gbuild -j${THREADS} -m3500 --commit bitcoin=${COMMIT} --url bitcoin="${PROJECT_ROOT}" "${PROJECT_ROOT}/contrib/gitian-descriptors/gitian-${OS_NAME}.yml"
 
 move_log
 mv result/*.yml "${OS_DIR}/"
 mv build/out/* "${OS_DIR}/"