diff --git a/pkgs/development/compilers/hare/setup-hook.sh b/pkgs/development/compilers/hare/setup-hook.sh
index d2d2c34354d..999b91df122 100644
--- a/pkgs/development/compilers/hare/setup-hook.sh
+++ b/pkgs/development/compilers/hare/setup-hook.sh
@@ -1,3 +1,5 @@
+export HARECACHE="$NIX_BUILD_TOP/.harecache"
+
 addHarepath () {
     for haredir in third-party stdlib; do
         if [[ -d "$1/src/hare/$haredir" ]]; then