diff --git a/typed-map-lib/typed-map/main.rkt b/typed-map-lib/typed-map/main.rkt
index 8f3963e..15074a2 100644
--- a/typed-map-lib/typed-map/main.rkt
+++ b/typed-map-lib/typed-map/main.rkt
@@ -85,4 +85,4 @@
                      upcast-result))))))]
     [(_ f init-acc lᵢ ...)
      (with-syntax ([(argᵢ ...) (generate-temporaries #'(lᵢ ...))])
-       #'(foldr (λ (argᵢ ... arg-acc) (f argᵢ ... arg-acc)) init-acc lᵢ ...))]))
+       #'(foldl (λ (argᵢ ... arg-acc) (f argᵢ ... arg-acc)) init-acc lᵢ ...))]))
diff --git a/typed-map-test/typed-map/test/gh-bug-2.rkt b/typed-map-test/typed-map/test/gh-bug-2.rkt
new file mode 100644
index 0000000..951fe0f
--- /dev/null
+++ b/typed-map-test/typed-map/test/gh-bug-2.rkt
@@ -0,0 +1,9 @@
+#lang typed/racket
+(require typed-map
+         typed/rackunit)
+
+(check-equal? (foldl (λ (x [acc : (Rec R (U Null (Pairof R Positive-Index)))])
+                       (cons acc (add1 x)))
+                     '()
+                     '(1 2 3))
+              '(((() . 2) . 3) . 4))
\ No newline at end of file