diff --git a/scripts/source_development_defaults.sh b/scripts/source_development_defaults.sh
--- a/scripts/source_development_defaults.sh
+++ b/scripts/source_development_defaults.sh
@@ -43,8 +43,10 @@
 export TEMP="$TMP"
 export TMPDIR="$TMP"
 export TEMPDIR="$TMP"
+export EM_CACHE="$TMP/em_cache"
+
+mkdir -p "$EM_CACHE"
 
-mkdir -p "$TMP"
 
 # For cargo + rustup applications, ensure cargo user bin directory is on path
 if [[ ! "$PATH" =~ \.cargo/bin ]]; then