From 781c775864d88b1305dcf060cf5ac400cee173cf Mon Sep 17 00:00:00 2001
From: Dillon Mulroy <dillon@cloudflare.com>
Date: Fri, 16 Jan 2026 10:48:00 -0500
Subject: [PATCH] fix(types): filter symbol keys in RpcCompatible mapped type

Use key remapping to filter out symbol keys instead of mapping to never.
Fixes Disposable compatibility issue with RPC types.

Ref: cloudflare/workerd#5804
---
 .changeset/fix-rpccompatible-symbol-keys.md | 5 +++++
 src/types.d.ts                              | 2 +-
 2 files changed, 6 insertions(+), 1 deletion(-)
 create mode 100644 .changeset/fix-rpccompatible-symbol-keys.md

diff --git a/.changeset/fix-rpccompatible-symbol-keys.md b/.changeset/fix-rpccompatible-symbol-keys.md
new file mode 100644
index 0000000..0b9bbf8
--- /dev/null
+++ b/.changeset/fix-rpccompatible-symbol-keys.md
@@ -0,0 +1,5 @@
+---
+"capnweb": patch
+---
+
+Fix RpcCompatible type to filter out symbol keys instead of mapping them to never
diff --git a/src/types.d.ts b/src/types.d.ts
index c5a2897..2c2e80e 100644
--- a/src/types.d.ts
+++ b/src/types.d.ts
@@ -33,7 +33,7 @@ export type RpcCompatible<T> =
   | Array<T extends Array<infer U> ? RpcCompatible<U> : never>
   | ReadonlyArray<T extends ReadonlyArray<infer U> ? RpcCompatible<U> : never>
   | {
-      [K in keyof T]: K extends number | string ? RpcCompatible<T[K]> : never;
+      [K in keyof T as K extends string | number ? K : never]: RpcCompatible<T[K]>;
     }
   | Promise<T extends Promise<infer U> ? RpcCompatible<U> : never>
   // Special types