diff --git a/d2js/js/make.sh b/d2js/js/make.sh
index b1537b6fe0..44535f5640 100755
--- a/d2js/js/make.sh
+++ b/d2js/js/make.sh
@@ -8,8 +8,14 @@ fi
 . "$(dirname "$0")/../../ci/sub/lib.sh"
 PATH="$(cd -- "$(dirname "$0")" && pwd)/../../ci/sub/bin:$PATH"
 cd -- "$(dirname "$0")"
+
+if ! command -v bun >/dev/null && [ -n "${CI-}" ]; then
+  curl -fsSL https://bun.sh/install | sh -s --
+fi
+
 if ! bun --version >/dev/null 2>&1; then
-  echoerr "You need bun to build d2js."
+  echoerr "You need bun to build d2.js: curl -fsSL https://bun.sh/install | bash"
   exit 1
 fi
+
 _make "$@"