diff --git a/pollen/private/cache-utils.rkt b/pollen/private/cache-utils.rkt
index d0e9315..251ce08 100644
--- a/pollen/private/cache-utils.rkt
+++ b/pollen/private/cache-utils.rkt
@@ -102,7 +102,8 @@
   (define dest-path ((match (key->type key)
                        ['source key->source-path]
                        ['output key->output-path]
-                       ['template (λ (k) (path-add-extension  (key->source-path key) (string->bytes/utf-8 (format ".~a-template" (current-poly-target)))))]) key))
+                       ;; path-add-suffix is deprecated since 6.5.0.3 but we still need compatibility with 6.3
+                       ['template (λ (k) (path-add-suffix  (key->source-path key) (string->bytes/utf-8 (format ".~a-template" (current-poly-target)))))]) key))
   (define-values (cache-dir private-cache-dir) (make-cache-dirs dest-path))
   (define-values (dest-path-dir dest-path-filename _) (split-path dest-path))
   (define dest-file (build-path cache-dir (format "~a.rktd" dest-path-filename)))
diff --git a/pollen/private/ts.rktd b/pollen/private/ts.rktd
index 9020ffe..4290e4c 100644
--- a/pollen/private/ts.rktd
+++ b/pollen/private/ts.rktd
@@ -1 +1 @@
-1580709571
+1580927197