diff --git a/packages/core/src/runtime/actor.ts b/packages/core/src/runtime/actor.ts
index 6c013eb..2f4d5ff 100644
--- a/packages/core/src/runtime/actor.ts
+++ b/packages/core/src/runtime/actor.ts
@@ -1,7 +1,7 @@
 /// SPDX-License-Identifier: GPL-3.0-or-later
 /// SPDX-FileCopyrightText: Copyright © 2016-2023 Tony Garnock-Jones <tonyg@leastfixedpoint.com>
 
-import { IdentitySet, Value, embeddedId, is, fromJS, stringify, Dictionary, KeyedSet } from '@preserves/core';
+import { IdentitySet, Value, embeddedId, is, fromJS, stringify, Dictionary, KeyedSet, Tuple } from '@preserves/core';
 import { Cell, Field, Graph } from './dataflow.js';
 import { Caveat, runRewrites } from './rewrite.js';
 import { ActorSpace } from './space.js';
@@ -181,6 +181,10 @@ export class Facet {
         this.outbound = initialAssertions;
     }
 
+    wrap<T extends Tuple<any>>(f: (... args: T) => void): (... args: T) => void {
+        return (... args) => this.turn(() => f(... args));
+    }
+
     turn(a: LocalAction) {
         Turn.for(this, a);
     }