diff --git a/lib/tree-updater.rkt b/lib/tree-updater.rkt
index 074c5a1..16a456d 100644
--- a/lib/tree-updater.rkt
+++ b/lib/tree-updater.rkt
@@ -3,6 +3,7 @@
          racket/function
          racket/match
          racket/string
+         profile-flame-graph
          "pure-utils.rkt"
          "url-utils.rkt"
          "xexpr-utils.rkt")
@@ -298,8 +299,34 @@
   ; check that noscript images are removed
   (check-equal? ((query-selector (λ (t a c) (eq? t 'noscript)) transformed)) #f)
   ; benchmark
-  (when (file-exists? "../storage/Frog.html")
-    (with-input-from-file "../storage/Frog.html"
+  (when (file-exists? "../storage/Block.html")
+    (with-input-from-file "../storage/Block.html"
       (λ ()
         (define tree (html->xexp (current-input-port)))
-        (time (length (update-tree-wiki tree "minecraft")))))))
+        (time (length (update-tree-wiki tree "minecraft"))))))
+
+  ; benchmark with flamegraph
+  ; these two flamegraphs need to be separated i think so that they resolve
+  ; different thunks. probably only need to be in two different with-input-file
+  ; blocks.
+  (when (file-exists? "../storage/Block.html")
+    (with-input-from-file "../storage/Block.html"
+      (λ ()
+        (define tree (html->xexp (current-input-port)))
+        (profile
+          (length (update-tree-wiki tree "minecraft"))
+          #:svg-path "../storage/Block-profile-errortrace.svg"
+          #:repeat 100
+          #:use-errortrace? #t)
+        )))
+  (when (file-exists? "../storage/Block.html")
+    (with-input-from-file "../storage/Block.html"
+      (λ ()
+        (define tree (html->xexp (current-input-port)))
+        (profile
+          (length (update-tree-wiki tree "minecraft"))
+          #:svg-path "../storage/Block-profile.svg"
+          #:repeat 100
+          #:use-errortrace? #f)
+        )))
+  )