diff --git a/theories/typing/function.v b/theories/typing/function.v
index b2f133b2158bf717e91a792b9d492ba209b7297a..eeea31facbc0b892f1cfd555252873304b83d9c5 100644
--- a/theories/typing/function.v
+++ b/theories/typing/function.v
@@ -132,18 +132,16 @@ Section typing.
         iApply (big_sepL_mono' with "Hvl"). by iIntros (i [v ty']).
   Qed.
 
-  Lemma type_fn {A m} E L E' fb kb (argsb : list binder) e
+  Lemma type_fn {A} E L E' fb kb (argsb : list binder) e
         (tys : A → vec type (length argsb)) ty
-        (cps : vec path m) (ctyl : vec type m) `{!LstCopy ctyl, !LstSend ctyl} :
+        T `{!CopyC T, !SendC T} :
     Closed (fb :b: kb :b: argsb +b+ []) e →
     (∀ x f k (args : vec val _),
         typed_body (E' x) [] [CCtx_iscont k [] 1 (λ v, [TCtx_hasty (v!!!0) (ty x)])]
                    (TCtx_hasty f (fn E' tys ty) ::
-                      zip_with (TCtx_hasty ∘ of_val) args (tys x) ++
-                      zip_with TCtx_hasty cps ctyl)
+                      zip_with (TCtx_hasty ∘ of_val) args (tys x) ++ T)
                    (subst' fb f $ subst_v (kb :: argsb) (vmap of_val $ k ::: args) e)) →
-    typed_instruction_ty E L (zip_with TCtx_hasty cps ctyl)
-                         (Rec fb (kb :: argsb) e) (fn E' tys ty).
+    typed_instruction_ty E L T (Rec fb (kb :: argsb) e) (fn E' tys ty).
   Proof.
     iIntros (Hc Hbody tid qE) "#HEAP #LFT $ $ $ #HT". iApply wp_value.
     { simpl. rewrite decide_left. done. }
@@ -155,6 +153,6 @@ Section typing.
     { by rewrite -vec_to_list_cons -vec_to_list_map -subst_v_eq. }
     iApply (Hbody with "* HEAP LFT Htl HE HL HC").
     rewrite tctx_interp_cons tctx_interp_app. iFrame "HT' IH".
-    iApply tctx_send. by iNext.
+    iApply sendc_change_tid. by iNext.
   Qed.
 End typing.
diff --git a/theories/typing/type_context.v b/theories/typing/type_context.v
index 9fd47d5ed635c8a0a8d03c6ca00eb6a261725d47..4b5c76b43c68189317758840121de91ec3eebb15 100644
--- a/theories/typing/type_context.v
+++ b/theories/typing/type_context.v
@@ -115,28 +115,37 @@ Section type_context.
     tctx_interp tid [x] ≡ tctx_elt_interp tid x.
   Proof. rewrite tctx_interp_cons tctx_interp_nil right_id //. Qed.
 
-  Global Instance tctx_persistent cps ctyl tid :
-    LstCopy ctyl → PersistentP (tctx_interp tid $ zip_with TCtx_hasty cps ctyl).
+  (** Copy typing contexts *)
+  Class CopyC (T : tctx) :=
+    copyc_persistent tid : PersistentP (tctx_interp tid T).
+  Global Existing Instances copyc_persistent.
+
+  Global Instance tctx_nil_copy : CopyC [].
+  Proof. rewrite /CopyC. apply _. Qed.
+
+  Global Instance tctx_ty_copy T p ty :
+    CopyC T → Copy ty → CopyC (TCtx_hasty p ty :: T).
   Proof.
-    intros Hcopy. revert cps; induction Hcopy; intros cps;
-      first by (rewrite zip_with_nil_r tctx_interp_nil; apply _).
-    destruct cps; first by (rewrite tctx_interp_nil; apply _). simpl.
     (* TODO RJ: Should we have instances that PersistentP respects equiv? *)
-    rewrite /PersistentP tctx_interp_cons.
+    intros ???. rewrite /PersistentP tctx_interp_cons.
     apply uPred.sep_persistent; by apply _.
   Qed.
 
-  Lemma tctx_send cps ctyl tid1 tid2 {Hcopy : LstSend ctyl} :
-    tctx_interp tid1 $ zip_with TCtx_hasty cps ctyl -∗
-                tctx_interp tid2 $ zip_with TCtx_hasty cps ctyl.
+  (** Send typing contexts *)
+  Class SendC (T : tctx) :=
+    sendc_change_tid tid1 tid2 : tctx_interp tid1 T -∗ tctx_interp tid2 T.
+
+  Global Instance tctx_nil_send : SendC [].
+  Proof. done. Qed.
+
+  Global Instance tctx_ty_send T p ty :
+    SendC T → Send ty → SendC (TCtx_hasty p ty :: T).
   Proof.
-    revert cps; induction Hcopy; intros cps;
-      first by rewrite zip_with_nil_r !tctx_interp_nil.
-    destruct cps; first by rewrite !tctx_interp_nil. simpl.
-    rewrite !tctx_interp_cons. iIntros "[Hty HT]". iSplitR "HT".
+    iIntros (HT Hty ??). rewrite !tctx_interp_cons.
+    iIntros "[Hty HT]". iSplitR "HT".
     - iDestruct "Hty" as (?) "[% Hty]". iExists _. iSplit; first done.
-      by iApply send_change_tid.
-    - by iApply IHHcopy.
+      by iApply Hty.
+    - by iApply HT.
   Qed.
 
   (** Type context inclusion *)