diff --git a/nix/ssh-wasm.nix b/nix/ssh-wasm.nix
index e4a3977..a7b0586 100644
--- a/nix/ssh-wasm.nix
+++ b/nix/ssh-wasm.nix
@@ -26,7 +26,7 @@ in
       # Patch Tailscale's derphttp to include DERPPort in WebSocket URLs.
       # Without this, DERP servers on non-443 ports fail in WASM builds.
       if [ -f patches/tailscale-derp-port.patch ]; then
-        chmod -R +w vendor/tailscale.com/derp/derphttp
+        chmod -R +w vendor/tailscale.com
         patch -d vendor/tailscale.com -p1 < patches/tailscale-derp-port.patch
       fi