diff --git a/zo-lib/compiler/zo-marshal.rkt b/zo-lib/compiler/zo-marshal.rkt
index 6c4e657a3d..10f11c0b70 100644
--- a/zo-lib/compiler/zo-marshal.rkt
+++ b/zo-lib/compiler/zo-marshal.rkt
@@ -1307,17 +1307,19 @@
 
 (define (encode-binding b name ht)
   (match b
-    [(free-id=?-binding base id)
+    [(free-id=?-binding base id phase)
      (hash-ref ht b
                (lambda ()
                  (match b
-                   [(free-id=?-binding base id)
+                   [(free-id=?-binding base id phase)
                     (define bx (box #f))
                     (hash-set! ht b bx)
                     (set-box! bx
-                              (cons (encode-binding base name ht)
-                                    (cons (stx-obj-datum id)
-                                          (stx-obj-wrap id))))])))]
+                              (cons
+                               (cons (encode-binding base name ht)
+                                     (cons (stx-obj-datum id)
+                                           (stx-obj-wrap id)))
+                               phase))])))]
     [_
      (hash-ref! ht b
                 (lambda ()
diff --git a/zo-lib/compiler/zo-parse.rkt b/zo-lib/compiler/zo-parse.rkt
index dc53a5bc75..9c411c323f 100644
--- a/zo-lib/compiler/zo-parse.rkt
+++ b/zo-lib/compiler/zo-parse.rkt
@@ -1298,10 +1298,11 @@
   (hash-ref! ht b
              (lambda ()
                (match b
-                 [(box (cons base-b (cons sym wraps)))
+                 [(box (cons base-b (cons (cons sym wraps) phase)))
                   (free-id=?-binding
                    (decode-binding base-b ht)
-                   (stx-obj sym wraps 'clean))]
+                   (stx-obj sym (decode-wrap wraps ht) 'clean)
+                   phase)]
                  [(? symbol?)
                   (local-binding b)]
                  [else
diff --git a/zo-lib/compiler/zo-structs.rkt b/zo-lib/compiler/zo-structs.rkt
index c1b83b3478..68af6f58e4 100644
--- a/zo-lib/compiler/zo-structs.rkt
+++ b/zo-lib/compiler/zo-structs.rkt
@@ -205,7 +205,8 @@
 (define-form-struct binding ())
 (define-form-struct (free-id=?-binding binding) ([base (and/c binding?
                                                               (not/c free-id=?-binding?))]
-                                                 [id stx-obj?]))
+                                                 [id stx-obj?]
+                                                 [phase (or/c #f exact-integer?)]))
 (define-form-struct (local-binding binding) ([name symbol?]))
 (define-form-struct (module-binding binding) ([encoded any/c]))
 ;; Convert `module-binding` to `decoded-module-binding` with `decode-module-binding`: