diff --git a/build b/build
index 5997541..56cc9cc 100755
--- a/build
+++ b/build
@@ -95,7 +95,7 @@ build_release()
 	cd "$srcdir" || $err "$vdir: !cd \"$srcdir\""
 	./update trees -f
 	rmgit .
-	x_ rm -Rf cache tmp
+	x_ rm -Rf tmp
 	x_ mv src/docs docs
 	) || $err "can't create release files"
 
diff --git a/include/git.sh b/include/git.sh
index 3a6247d..f8441f3 100644
--- a/include/git.sh
+++ b/include/git.sh
@@ -37,7 +37,7 @@ fetch_project()
 
 clone_project()
 {
-	loc="cache/repo/$project" && singletree "$project" && \
+	loc="$XBMK_CACHE/repo/$project" && singletree "$project" && \
 	    loc="src/$project"
 
 	printf "Downloading project '%s' to '%s'\n" "$project" "$loc"
@@ -62,8 +62,9 @@ git_prep()
 	[ "$project" = "coreboot" ] && [ -n "$xtree" ] && [ $# -gt 2 ] && \
 	    [ "$xtree" != "$tree" ] && link_crossgcc "$_loc"
 
-	[ "$XBMK_RELEASE" = "y" ] && [ "$_loc" != "cache/repo/$project" ] \
-	    && rmgit "$tmpgit"
+	[ "$XBMK_RELEASE" = "y" ] && \
+	    [ "$_loc" != "$XBMK_CACHE/repo/$project" ] && \
+		rmgit "$tmpgit"
 
 	move_repo "$_loc"
 }
@@ -106,8 +107,8 @@ tmpclone()
 	repofail="n"
 
 	[ $# -lt 6 ] || rm -Rf "$3" || $err "git retry: !rm $3 ($1)"
-	repodir="cache/repo/${1##*/}" && [ $# -gt 5 ] && repodir="$3"
-	x_ mkdir -p "cache/repo"
+	repodir="$XBMK_CACHE/repo/${1##*/}" && [ $# -gt 5 ] && repodir="$3"
+	mkdir -p "$XBMK_CACHE/repo" || $err "!rmdir $XBMK_CACHE/repo"
 	if [ -d "$repodir" ] && [ $# -lt 6 ]; then
 		git -C "$repodir" pull || sleep 3 || git -C "$repodir" pull \
 		    || sleep 3 || git -C "$repodir" pull || :
diff --git a/include/lib.sh b/include/lib.sh
index 791ab4e..2cd8c0d 100644
--- a/include/lib.sh
+++ b/include/lib.sh
@@ -88,6 +88,14 @@ if [ -z "${TMPDIR+x}" ]; then
 	xbmk_parent="y"
 fi
 
+# XBMK_CACHE is a directory, for caching downloads and git repositories
+[ -z "${XBMK_CACHE+x}" ] && export XBMK_CACHE="$PWD/cache"
+[ -z "$XBMK_CACHE" ] && export XBMK_CACHE="$PWD/cache"
+[ -L "$XBMK_CACHE" ] && [ "$XBMK_CACHE" = "$PWD/cache" ] && \
+    $err "cachedir is default, $PWD/cache, but it exists and is a symlink"
+[ -L "$XBMK_CACHE" ] && export XBMK_CACHE="$PWD/cache"
+[ -f "$XBMK_CACHE" ] && $err "cachedir '$XBMK_CACHE' exists but it's a file"
+
 # if "y": a coreboot target won't be built if target.cfg says release="n"
 # (this is used to exclude certain build targets from releases)
 [ -z "${XBMK_RELEASE+x}" ] && export XBMK_RELEASE="n"
@@ -180,14 +188,16 @@ singletree()
 
 download()
 {
-	cached="cache/file/$4"
+	cached="$XBMK_CACHE/file/$4"
 	dl_fail="n" # 1 url, 2 url backup, 3 destination, 4 checksum
 	vendor_checksum "$4" "$cached" 2>/dev/null && dl_fail="y"
 	[ "$dl_fail" = "n" ] && e "$3" f && return 0
-	x_ mkdir -p "${3%/*}" cache/file && for url in "$1" "$2"; do
+	mkdir -p "${3%/*}" "$XBMK_CACHE/file" || \
+	    $err "!mkdir '$3' '$XBMK_CACHE/file'"
+	for url in "$1" "$2"; do
 		[ "$dl_fail" = "n" ] && break
 		[ -z "$url" ] && continue
-		x_ rm -f "$cached"
+		rm -f "$cached" || $err "!rm -f '$cached'"
 		curl --location --retry 3 -A "$_ua" "$url" -o "$cached" || \
 		    wget --tries 3 -U "$_ua" "$url" -O "$cached" || continue
 		vendor_checksum "$4" "$cached" || dl_fail="n"
diff --git a/script/trees b/script/trees
index 2cee435..ce6da42 100755
--- a/script/trees
+++ b/script/trees
@@ -165,11 +165,11 @@ build_dependencies()
 
 check_project_hashes()
 {
-	x_ mkdir -p cache/hash
+	mkdir -p "$XBMK_CACHE/hash" || $err "!mkdir '$XBMK_CACHE/hash'"
 
 	old_pjhash=""
-	[ ! -f "cache/hash/$project$tree" ] || \
-	    read -r old_pjhash < "cache/hash/$project$tree"
+	[ ! -f "$XBMK_CACHE/hash/$project$tree" ] || \
+	    read -r old_pjhash < "$XBMK_CACHE/hash/$project$tree"
 
 	x_ rm -f "$TMPDIR/project.list" "$TMPDIR/project.hash" \
 	    "$TMPDIR/project.tmp"; x_ touch "$TMPDIR/project.tmp"
@@ -192,10 +192,10 @@ check_project_hashes()
 
 	pjhash="$(sha512sum "$TMPDIR/project.hash" | awk '{print $1}')" || :
 	badhash="y" && [ "$pjhash" = "$old_pjhash" ] && badhash="n"
-	[ -f "cache/hash/$project$tree" ] || badhash="y"
+	[ -f "$XBMK_CACHE/hash/$project$tree" ] || badhash="y"
 
-	printf "%s\n" "$pjhash" > "cache/hash/$project$tree" || \
-	    $err "!mk cache/hash/$project$tree"
+	printf "%s\n" "$pjhash" > "$XBMK_CACHE/hash/$project$tree" || \
+	    $err "!mk $XBMK_CACHE/hash/$project$tree"
 
 	[ "$badhash" = "n" ] || rm -Rf "src/$project/$tree" \
 	    "elf/$project/$tree" "elf/$project/$target" || \