diff --git a/packages/SwingSet/src/controller.js b/packages/SwingSet/src/controller.js
index 21f0ca130fa..7de56351f11 100644
--- a/packages/SwingSet/src/controller.js
+++ b/packages/SwingSet/src/controller.js
@@ -20,6 +20,7 @@ import { xsnap, makeSnapstore } from '@agoric/xsnap';
 import { WeakRef, FinalizationRegistry } from './weakref';
 import { startSubprocessWorker } from './spawnSubprocessWorker';
 import { waitUntilQuiescent } from './waitUntilQuiescent';
+import { gcAndFinalize } from './gc';
 import { insistStorageAPI } from './storageAPI';
 import { insistCapData } from './capdata';
 import { parseVatSlot } from './parseVatSlots';
@@ -271,7 +272,8 @@ export async function makeSwingsetController(
     const supercode = require.resolve(
       './kernel/vatManager/supervisor-subprocess-node.js',
     );
-    return startSubprocessWorker(process.execPath, ['-r', 'esm', supercode]);
+    const args = ['--expose-gc', '-r', 'esm', supercode];
+    return startSubprocessWorker(process.execPath, args);
   }
 
   const bundles = [
@@ -297,6 +299,7 @@ export async function makeSwingsetController(
     writeSlogObject,
     WeakRef,
     FinalizationRegistry,
+    gcAndFinalize,
   };
 
   const kernelOptions = { verbose };
diff --git a/packages/SwingSet/src/kernel/kernel.js b/packages/SwingSet/src/kernel/kernel.js
index 607e543ee84..77bdf37f813 100644
--- a/packages/SwingSet/src/kernel/kernel.js
+++ b/packages/SwingSet/src/kernel/kernel.js
@@ -105,6 +105,7 @@ export default function buildKernel(
     writeSlogObject,
     WeakRef,
     FinalizationRegistry,
+    gcAndFinalize,
   } = kernelEndowments;
   deviceEndowments = { ...deviceEndowments }; // copy so we can modify
   const { verbose, defaultManagerType = 'local' } = kernelOptions;
@@ -631,7 +632,12 @@ export default function buildKernel(
     }
   }
 
-  const gcTools = harden({ WeakRef, FinalizationRegistry, waitUntilQuiescent });
+  const gcTools = harden({
+    WeakRef,
+    FinalizationRegistry,
+    waitUntilQuiescent,
+    gcAndFinalize,
+  });
   const vatManagerFactory = makeVatManagerFactory({
     allVatPowers,
     kernelKeeper,
diff --git a/packages/SwingSet/src/kernel/liveSlots.js b/packages/SwingSet/src/kernel/liveSlots.js
index 48f9ed308f5..d0fd49a8f55 100644
--- a/packages/SwingSet/src/kernel/liveSlots.js
+++ b/packages/SwingSet/src/kernel/liveSlots.js
@@ -25,7 +25,7 @@ const DEFAULT_VIRTUAL_OBJECT_CACHE_SIZE = 3; // XXX ridiculously small value to
  * @param {boolean} enableDisavow
  * @param {*} vatPowers
  * @param {*} vatParameters
- * @param {*} gcTools { WeakRef, FinalizationRegistry, waitUntilQuiescent }
+ * @param {*} gcTools { WeakRef, FinalizationRegistry, waitUntilQuiescent, gcAndFinalize }
  * @param {Console} console
  * @returns {*} { vatGlobals, inescapableGlobalProperties, dispatch, setBuildRootObject }
  *
diff --git a/packages/SwingSet/src/kernel/vatManager/manager-local.js b/packages/SwingSet/src/kernel/vatManager/manager-local.js
index 0a244e4bc9f..f1c2e3fa759 100644
--- a/packages/SwingSet/src/kernel/vatManager/manager-local.js
+++ b/packages/SwingSet/src/kernel/vatManager/manager-local.js
@@ -20,7 +20,6 @@ export function makeLocalVatManagerFactory(tools) {
     kernelSlog,
   } = tools;
 
-  const { waitUntilQuiescent } = gcTools;
   const { makeGetMeter, refillAllMeters, stopGlobalMeter } = meterManager;
   const baseVP = {
     makeMarshal: allVatPowers.makeMarshal,
@@ -42,7 +41,7 @@ export function makeLocalVatManagerFactory(tools) {
       assert.typeof(dispatch, 'function');
       // this 'deliverToWorker' never throws, even if liveslots has an internal error
       const deliverToWorker = makeMeteredDispatch(
-        makeSupervisorDispatch(dispatch, waitUntilQuiescent),
+        makeSupervisorDispatch(dispatch),
         mtools,
       );
       mk.setDeliverToWorker(deliverToWorker);
diff --git a/packages/SwingSet/src/kernel/vatManager/supervisor-helper.js b/packages/SwingSet/src/kernel/vatManager/supervisor-helper.js
index 78e03f34601..7a2a0833746 100644
--- a/packages/SwingSet/src/kernel/vatManager/supervisor-helper.js
+++ b/packages/SwingSet/src/kernel/vatManager/supervisor-helper.js
@@ -18,11 +18,9 @@ import '../../types';
  * manager process.
  *
  * @param { VatDispatcherSyncAsync } dispatch
- * @param { WaitUntilQuiescent } waitUntilQuiescent
  * @returns { VatDispatcher }
  */
-function makeSupervisorDispatch(dispatch, waitUntilQuiescent) {
-  assert.typeof(waitUntilQuiescent, 'function');
+function makeSupervisorDispatch(dispatch) {
   /**
    * @param { VatDeliveryObject } delivery
    * @returns { Promise<VatDeliveryResult> }
diff --git a/packages/SwingSet/src/kernel/vatManager/supervisor-nodeworker.js b/packages/SwingSet/src/kernel/vatManager/supervisor-nodeworker.js
index 4890fab2f5c..b468aba2262 100644
--- a/packages/SwingSet/src/kernel/vatManager/supervisor-nodeworker.js
+++ b/packages/SwingSet/src/kernel/vatManager/supervisor-nodeworker.js
@@ -10,6 +10,7 @@ import { assert, details as X } from '@agoric/assert';
 import { importBundle } from '@agoric/import-bundle';
 import { makeMarshal } from '@agoric/marshal';
 import { WeakRef, FinalizationRegistry } from '../../weakref';
+import { gcAndFinalize } from '../../gc';
 import { waitUntilQuiescent } from '../../waitUntilQuiescent';
 import { makeLiveSlots } from '../liveSlots';
 import {
@@ -78,6 +79,7 @@ parentPort.on('message', ([type, ...margs]) => {
       WeakRef,
       FinalizationRegistry,
       waitUntilQuiescent,
+      gcAndFinalize,
     });
     const ls = makeLiveSlots(
       syscall,
@@ -102,7 +104,7 @@ parentPort.on('message', ([type, ...margs]) => {
         workerLog(`got vatNS:`, Object.keys(vatNS).join(','));
         sendUplink(['gotBundle']);
         ls.setBuildRootObject(vatNS.buildRootObject);
-        dispatch = makeSupervisorDispatch(ls.dispatch, waitUntilQuiescent);
+        dispatch = makeSupervisorDispatch(ls.dispatch);
         workerLog(`got dispatch:`, Object.keys(dispatch).join(','));
         sendUplink(['dispatchReady']);
       },
diff --git a/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-node.js b/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-node.js
index 87b3268ce3f..49dda5f201a 100644
--- a/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-node.js
+++ b/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-node.js
@@ -8,6 +8,7 @@ import { assert, details as X } from '@agoric/assert';
 import { importBundle } from '@agoric/import-bundle';
 import { makeMarshal } from '@agoric/marshal';
 import { WeakRef, FinalizationRegistry } from '../../weakref';
+import { gcAndFinalize } from '../../gc';
 import { arrayEncoderStream, arrayDecoderStream } from '../../worker-protocol';
 import {
   netstringEncoderStream,
@@ -91,6 +92,7 @@ fromParent.on('data', ([type, ...margs]) => {
       WeakRef,
       FinalizationRegistry,
       waitUntilQuiescent,
+      gcAndFinalize,
     });
     const ls = makeLiveSlots(
       syscall,
diff --git a/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-xsnap.js b/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-xsnap.js
index 803b122424d..965a8c46bec 100644
--- a/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-xsnap.js
+++ b/packages/SwingSet/src/kernel/vatManager/supervisor-subprocess-xsnap.js
@@ -6,6 +6,7 @@ import { makeMarshal } from '@agoric/marshal';
 import '../../types';
 // grumble... waitUntilQuiescent is exported and closes over ambient authority
 import { waitUntilQuiescent } from '../../waitUntilQuiescent';
+import { gcAndFinalize } from '../../gc';
 import { insistVatDeliveryObject, insistVatSyscallResult } from '../../message';
 
 import { makeLiveSlots } from '../liveSlots';
@@ -184,6 +185,7 @@ function makeWorker(port) {
       WeakRef,
       FinalizationRegistry,
       waitUntilQuiescent,
+      gcAndFinalize,
     });
 
     const ls = makeLiveSlots(
@@ -213,7 +215,7 @@ function makeWorker(port) {
     workerLog(`got vatNS:`, Object.keys(vatNS).join(','));
     ls.setBuildRootObject(vatNS.buildRootObject);
     assert(ls.dispatch);
-    dispatch = makeSupervisorDispatch(ls.dispatch, waitUntilQuiescent);
+    dispatch = makeSupervisorDispatch(ls.dispatch);
     workerLog(`got dispatch`);
     return ['dispatchReady'];
   }
diff --git a/packages/SwingSet/test/liveslots-helpers.js b/packages/SwingSet/test/liveslots-helpers.js
index 90a54637d5e..9bede1a2284 100644
--- a/packages/SwingSet/test/liveslots-helpers.js
+++ b/packages/SwingSet/test/liveslots-helpers.js
@@ -1,5 +1,6 @@
 import { WeakRef, FinalizationRegistry } from '../src/weakref';
 import { waitUntilQuiescent } from '../src/waitUntilQuiescent';
+import { gcAndFinalize } from '../src/gc';
 import { makeLiveSlots } from '../src/kernel/liveSlots';
 
 export function buildSyscall() {
@@ -38,7 +39,12 @@ export function makeDispatch(
   vatID = 'vatA',
   enableDisavow = false,
 ) {
-  const gcTools = harden({ WeakRef, FinalizationRegistry, waitUntilQuiescent });
+  const gcTools = harden({
+    WeakRef,
+    FinalizationRegistry,
+    waitUntilQuiescent,
+    gcAndFinalize,
+  });
   const { setBuildRootObject, dispatch } = makeLiveSlots(
     syscall,
     vatID,
diff --git a/packages/SwingSet/test/test-liveslots.js b/packages/SwingSet/test/test-liveslots.js
index 41ec69857c4..66bc53b1f5b 100644
--- a/packages/SwingSet/test/test-liveslots.js
+++ b/packages/SwingSet/test/test-liveslots.js
@@ -811,12 +811,15 @@ function makeMockGC() {
     return allFRs;
   }
 
+  function mockGCAndFinalize() {}
+
   return harden({
     WeakRef: mockWeakRef,
     FinalizationRegistry: mockFinalizationRegistry,
     kill,
     getAllFRs,
     waitUntilQuiescent,
+    gcAndFinalize: mockGCAndFinalize,
   });
 }