diff --git a/org-ql.el b/org-ql.el
index 7a9755f..1699db6 100644
--- a/org-ql.el
+++ b/org-ql.el
@@ -1,3 +1,6 @@
+;; -*- lexical-binding: t; -*-
+
+
 ;;; Code:
 
 ;;;; Requirements
@@ -79,30 +82,31 @@ Headings should return non-nil for any ANY-PREDS and nil for all
 NONE-PREDS.  If NARROW is non-nil, buffer will not be widened
 first."
   ;; Cache `org-today' so we don't have to run it repeatedly.
-  (cl-letf ((today org-ql--today))
-    (org-ql--fmap ((category #'org-ql--category-p)
-                   (date #'org-ql--date-plain-p)
-                   (deadline #'org-ql--deadline-p)
-                   (scheduled #'org-ql--scheduled-p)
-                   (closed #'org-ql--closed-p)
-                   (habit #'org-ql--habit-p)
-                   (priority #'org-ql--priority-p)
-                   (todo #'org-ql--todo-p)
-                   (done #'org-ql--done-p)
-                   (tags #'org-ql--tags-p)
-                   (property #'org-ql--property-p)
-                   (regexp #'org-ql--regexp-p)
-                   (org-back-to-heading #'outline-back-to-heading))
-      (save-excursion
-        (save-restriction
-          (unless narrow
-            (widen))
-          (goto-char (point-min))
-          (when (org-before-first-heading-p)
-            (outline-next-heading))
-          (cl-loop when (funcall pred)
-                   collect (org-element-headline-parser (line-end-position))
-                   while (outline-next-heading)))))))
+  (let (today)
+    (cl-letf ((today org-ql--today))
+      (org-ql--fmap ((category #'org-ql--category-p)
+                     (date #'org-ql--date-plain-p)
+                     (deadline #'org-ql--deadline-p)
+                     (scheduled #'org-ql--scheduled-p)
+                     (closed #'org-ql--closed-p)
+                     (habit #'org-ql--habit-p)
+                     (priority #'org-ql--priority-p)
+                     (todo #'org-ql--todo-p)
+                     (done #'org-ql--done-p)
+                     (tags #'org-ql--tags-p)
+                     (property #'org-ql--property-p)
+                     (regexp #'org-ql--regexp-p)
+                     (org-back-to-heading #'outline-back-to-heading))
+        (save-excursion
+          (save-restriction
+            (unless narrow
+              (widen))
+            (goto-char (point-min))
+            (when (org-before-first-heading-p)
+              (outline-next-heading))
+            (cl-loop when (funcall pred)
+                     collect (org-element-headline-parser (line-end-position))
+                     while (outline-next-heading))))))))
 
 ;;;;; Predicates