diff --git a/packages/boot/test/bootstrapTests/ibcBridgeMock.js b/packages/boot/test/bootstrapTests/ibcBridgeMock.js
deleted file mode 100644
index 0f20af5162a..00000000000
--- a/packages/boot/test/bootstrapTests/ibcBridgeMock.js
+++ /dev/null
@@ -1,60 +0,0 @@
-// @ts-check
-import {
-  makePinnedHistoryTopic,
-  prepareDurablePublishKit,
-  subscribeEach,
-} from '@agoric/notifier';
-import { M } from '@endo/patterns';
-import { makeScalarBigMapStore } from '@agoric/vat-data';
-import { makeDurableZone } from '@agoric/zone/durable.js';
-
-// TODO: factor out overlap with packages/vats/test/network.test.js
-export const makeBridge = (
-  t,
-  baggage = makeScalarBigMapStore('baggage', {
-    keyShape: M.string(),
-    durable: true,
-  }),
-  zone = makeDurableZone(baggage),
-) => {
-  const makeDurablePublishKit = prepareDurablePublishKit(
-    baggage,
-    'DurablePublishKit',
-  );
-
-  const { subscriber, publisher } = makeDurablePublishKit();
-
-  const pinnedHistoryTopic = makePinnedHistoryTopic(subscriber);
-  const events = subscribeEach(pinnedHistoryTopic)[Symbol.asyncIterator]();
-
-  let hndlr;
-  /** @type {import('@agoric/vats/src/types.js').ScopedBridgeManager} */
-  const bridgeHandler = zone.exo('IBC Bridge Manager', undefined, {
-    toBridge: async obj => {
-      const { method, type, ...params } = obj;
-      publisher.publish([method, params]);
-      t.is(type, 'IBC_METHOD');
-      if (method === 'sendPacket') {
-        const { packet } = params;
-        return { ...packet, sequence: '39' };
-      }
-      return undefined;
-    },
-    fromBridge: async obj => {
-      if (!hndlr) throw Error('no handler!');
-      // EV must be late-bound; it is not availble at bridge construction time.
-      const { EV } = t.context.runutils;
-      await EV(hndlr).fromBridge(obj);
-    },
-    initHandler: h => {
-      if (hndlr) throw Error('already init');
-      hndlr = h;
-    },
-    setHandler: h => {
-      if (!hndlr) throw Error('must init first');
-      hndlr = h;
-    },
-  });
-
-  return { bridgeHandler, events };
-};
diff --git a/packages/boot/test/bootstrapTests/net-ibc-upgrade.test.ts b/packages/boot/test/bootstrapTests/net-ibc-upgrade.test.ts
index 3ac734c684f..47dcc7d963c 100644
--- a/packages/boot/test/bootstrapTests/net-ibc-upgrade.test.ts
+++ b/packages/boot/test/bootstrapTests/net-ibc-upgrade.test.ts
@@ -1,13 +1,15 @@
 /** @file upgrade network / IBC vat at many points in state machine */
-import { test as anyTest } from '@agoric/zoe/tools/prepare-test-env-ava.js';
-import { createRequire } from 'module';
-import type { TestFn } from 'ava';
-import type { BridgeHandler } from '@agoric/vats';
 import { BridgeId } from '@agoric/internal';
+import type { BridgeHandler } from '@agoric/vats';
+import { makeFakeIbcBridge } from '@agoric/vats/tools/fake-bridge.js';
+import { test as anyTest } from '@agoric/zoe/tools/prepare-test-env-ava.js';
 import { makeNodeBundleCache } from '@endo/bundle-source/cache.js';
-// import { E } from '@endo/eventual-send';
-import { V as E } from '@agoric/vow/vat.js';
-import { makeBridge } from './ibcBridgeMock.js';
+import type { TestFn } from 'ava';
+import { createRequire } from 'module';
+
+import type { Baggage } from '@agoric/swingset-liveslots';
+import { M, makeScalarBigMapStore } from '@agoric/vat-data';
+import { makeDurableZone } from '@agoric/zone/durable.js';
 import { makeSwingsetTestKit } from '../../tools/supports.ts';
 
 const { entries, assign } = Object;
@@ -22,7 +24,13 @@ const asset = {
 
 export const makeTestContext = async t => {
   console.time('DefaultTestContext');
-  const { bridgeHandler, events } = makeBridge(t);
+
+  const baggage = makeScalarBigMapStore('baggage', {
+    keyShape: M.string(),
+    durable: true,
+  }) as Baggage;
+  const zone = makeDurableZone(baggage);
+
   const bundleDir = 'bundles/vaults';
   const bundleCache = await makeNodeBundleCache(
     bundleDir,
@@ -31,9 +39,6 @@ export const makeTestContext = async t => {
   );
   const swingsetTestKit = await makeSwingsetTestKit(t.log, bundleDir, {
     configSpecifier: PLATFORM_CONFIG,
-    bridgeHandlers: {
-      [BridgeId.DIBC]: obj => bridgeHandler.toBridge(obj),
-    },
   });
   console.timeLog('DefaultTestContext', 'swingsetTestKit');
 
diff --git a/packages/boot/test/bootstrapTests/vats-restart.test.ts b/packages/boot/test/bootstrapTests/vats-restart.test.ts
index bd1f3340fef..fd3c35ef96f 100644
--- a/packages/boot/test/bootstrapTests/vats-restart.test.ts
+++ b/packages/boot/test/bootstrapTests/vats-restart.test.ts
@@ -110,7 +110,7 @@ test.serial('make IBC callbacks before upgrade', async t => {
   const vatStore = await EV.vat('bootstrap').consumeItem('vatStore');
   const { root: ibc } = await EV(vatStore).get('ibc');
   t.log('E(ibc).makeCallbacks(m1)');
-  const dummyBridgeManager = null as unknown as ScopedBridgeManager;
+  const dummyBridgeManager = null as unknown as ScopedBridgeManager<any>;
   const callbacks = await EV(ibc).makeCallbacks(dummyBridgeManager);
   t.truthy(callbacks);
   t.context.shared.ibcCallbacks = callbacks;
diff --git a/packages/boot/tools/supports.ts b/packages/boot/tools/supports.ts
index 882a4b14073..ee211d1c89a 100644
--- a/packages/boot/tools/supports.ts
+++ b/packages/boot/tools/supports.ts
@@ -249,7 +249,6 @@ export const matchIter = (t: AvaT, iter, valueRef) => {
  * @param [options.profileVats]
  * @param [options.debugVats]
  * @param [options.defaultManagerType]
- * @param [options.bridgeHandlers]
  */
 export const makeSwingsetTestKit = async (
   log: (..._: any[]) => void,
@@ -262,7 +261,6 @@ export const makeSwingsetTestKit = async (
     profileVats = [] as string[],
     debugVats = [] as string[],
     defaultManagerType = 'local' as ManagerType,
-    bridgeHandlers = {} as Record<string, (obj: any) => unknown>,
   } = {},
 ) => {
   console.time('makeBaseSwingsetTestKit');
@@ -305,9 +303,6 @@ export const makeSwingsetTestKit = async (
     }
     outboundMessages.get(bridgeId).push(obj);
 
-    if (bridgeId in bridgeHandlers) {
-      return bridgeHandlers[bridgeId](obj);
-    }
     switch (bridgeId) {
       case BridgeId.BANK: {
         trace(
diff --git a/packages/inter-protocol/test/smartWallet/contexts.js b/packages/inter-protocol/test/smartWallet/contexts.js
index a2cb53e6919..99dd01ef4f1 100644
--- a/packages/inter-protocol/test/smartWallet/contexts.js
+++ b/packages/inter-protocol/test/smartWallet/contexts.js
@@ -104,6 +104,11 @@ export const makeDefaultTestContext = async (t, makeSpace) => {
     'anyAddress',
   );
   const bridgeManager = await consume.bridgeManager;
+  /**
+   * @type {| undefined
+   *   | import('@agoric/vats').ScopedBridgeManager<'wallet'>}
+   */
+  // @ts-expect-error XXX EProxy
   const walletBridgeManager = await (bridgeManager &&
     E(bridgeManager).register(BridgeId.WALLET));
   const walletFactory = await E(zoe).startInstance(
diff --git a/packages/internal/src/config.js b/packages/internal/src/config.js
index 2a68eb09c97..e401317d15c 100644
--- a/packages/internal/src/config.js
+++ b/packages/internal/src/config.js
@@ -14,7 +14,7 @@
 /**
  * Event source ids used by the bridge device.
  */
-export const BridgeId = {
+export const BridgeId = /** @type {const} */ ({
   BANK: 'bank',
   CORE: 'core',
   DIBC: 'dibc',
@@ -24,8 +24,9 @@ export const BridgeId = {
   VLOCALCHAIN: 'vlocalchain',
   VTRANSFER: 'vtransfer',
   WALLET: 'wallet',
-};
+});
 harden(BridgeId);
+/** @typedef {(typeof BridgeId)[keyof typeof BridgeId]} BridgeIdValue */
 
 export const CosmosInitKeyToBridgeId = {
   vbankPort: BridgeId.BANK,
diff --git a/packages/orchestration/test/examples/swapExample.test.ts b/packages/orchestration/test/examples/swapExample.test.ts
index b989dd49d4a..86b364bf441 100644
--- a/packages/orchestration/test/examples/swapExample.test.ts
+++ b/packages/orchestration/test/examples/swapExample.test.ts
@@ -9,7 +9,7 @@ import { makeHeapZone } from '@agoric/zone';
 import { prepareLocalChainTools } from '@agoric/vats/src/localchain.js';
 import { buildRootObject as buildBankVatRoot } from '@agoric/vats/src/vat-bank.js';
 import { withAmountUtils } from '@agoric/zoe/tools/test-utils.js';
-import { makeBridge } from '../supports.js';
+import { makeFakeLocalchainBridge } from '../supports.js';
 
 const dirname = path.dirname(new URL(import.meta.url).pathname);
 
@@ -34,11 +34,11 @@ test('start', async t => {
 
   await E(bankManager).addAsset('uist', 'IST', 'Inter Stable Token', issuerKit);
 
-  const fakeBridgeKit = makeBridge(t);
+  const localchainBridge = makeFakeLocalchainBridge(zone);
 
   const localchain = makeLocalChain({
     bankManager,
-    system: fakeBridgeKit.bridgeHandler,
+    system: localchainBridge,
   });
 
   const storage = makeFakeStorageKit('mockChainStorageRoot', {
diff --git a/packages/orchestration/test/examples/unbondExample.test.ts b/packages/orchestration/test/examples/unbondExample.test.ts
index e79376c72d3..eebe0bcb930 100644
--- a/packages/orchestration/test/examples/unbondExample.test.ts
+++ b/packages/orchestration/test/examples/unbondExample.test.ts
@@ -9,7 +9,7 @@ import { withAmountUtils } from '@agoric/zoe/tools/test-utils.js';
 import { makeHeapZone } from '@agoric/zone';
 import { E } from '@endo/far';
 import path from 'path';
-import { makeBridge } from '../supports.js';
+import { makeFakeLocalchainBridge } from '../supports.js';
 
 const dirname = path.dirname(new URL(import.meta.url).pathname);
 
@@ -34,11 +34,11 @@ test('start', async t => {
 
   await E(bankManager).addAsset('uist', 'IST', 'Inter Stable Token', issuerKit);
 
-  const fakeBridgeKit = makeBridge(t);
+  const localchainBridge = makeFakeLocalchainBridge(zone);
 
   const localchain = makeLocalChain({
     bankManager,
-    system: fakeBridgeKit.bridgeHandler,
+    system: localchainBridge,
   });
 
   const storage = makeFakeStorageKit('mockChainStorageRoot', {
diff --git a/packages/orchestration/test/supports.ts b/packages/orchestration/test/supports.ts
index da8af128eac..7e8600ad2f4 100644
--- a/packages/orchestration/test/supports.ts
+++ b/packages/orchestration/test/supports.ts
@@ -1,66 +1 @@
-import { Fail } from '@agoric/assert';
-import type { ScopedBridgeManager } from '@agoric/vats';
-
-import {
-  makePinnedHistoryTopic,
-  prepareDurablePublishKit,
-  subscribeEach,
-} from '@agoric/notifier';
-import type { Baggage } from '@agoric/swingset-liveslots';
-import { M, makeScalarBigMapStore } from '@agoric/vat-data';
-import { makeDurableZone } from '@agoric/zone/durable.js';
-import type { ExecutionContext } from 'ava';
-
-// TODO DRY with ibcBridgeMock.js in package boot
-export const makeBridge = (
-  t: ExecutionContext,
-  baggage = makeScalarBigMapStore('baggage', {
-    keyShape: M.string(),
-    durable: true,
-  }) as Baggage,
-  zone = makeDurableZone(baggage),
-) => {
-  const makeDurablePublishKit = prepareDurablePublishKit(
-    baggage,
-    'DurablePublishKit',
-  );
-
-  const { subscriber, publisher } = makeDurablePublishKit();
-
-  const pinnedHistoryTopic = makePinnedHistoryTopic(subscriber);
-  const events = subscribeEach(pinnedHistoryTopic)[Symbol.asyncIterator]();
-
-  let hndlr;
-
-  const bridgeHandler: ScopedBridgeManager = zone.exo(
-    'IBC Bridge Manager',
-    undefined,
-    {
-      toBridge: async obj => {
-        const { method, type, ...params } = obj;
-        publisher.publish([method, params]);
-        console.info('toBridge', type, method, params);
-        switch (type) {
-          case 'VLOCALCHAIN_ALLOCATE_ADDRESS':
-            return 'agoric1fixme';
-          default:
-            Fail`unknown type ${type}`;
-        }
-        return undefined;
-      },
-      fromBridge: async obj => {
-        console.info('fromBridge', obj);
-      },
-      initHandler: h => {
-        if (hndlr) throw Error('already init');
-        hndlr = h;
-      },
-      setHandler: h => {
-        if (!hndlr) throw Error('must init first');
-        hndlr = h;
-      },
-    },
-  );
-
-  return { bridgeHandler, events };
-};
+export { makeFakeLocalchainBridge } from '@agoric/vats/tools/fake-bridge.js';
diff --git a/packages/smart-wallet/src/walletFactory.js b/packages/smart-wallet/src/walletFactory.js
index 9a751d74929..41c40f9f35b 100644
--- a/packages/smart-wallet/src/walletFactory.js
+++ b/packages/smart-wallet/src/walletFactory.js
@@ -142,7 +142,7 @@ export const makeAssetRegistry = assetPublisher => {
  * @param {ZCF<SmartWalletContractTerms>} zcf
  * @param {{
  *   storageNode: ERef<StorageNode>,
- *   walletBridgeManager?: ERef<import('@agoric/vats').ScopedBridgeManager>,
+ *   walletBridgeManager?: ERef<import('@agoric/vats').ScopedBridgeManager<'wallet'>>,
  *   walletReviver?: ERef<WalletReviver>,
  * }} privateArgs
  * @param {import('@agoric/vat-data').Baggage} baggage
diff --git a/packages/smart-wallet/test/contexts.js b/packages/smart-wallet/test/contexts.js
index 728c64a090a..a5e67942439 100644
--- a/packages/smart-wallet/test/contexts.js
+++ b/packages/smart-wallet/test/contexts.js
@@ -38,6 +38,8 @@ export const makeDefaultTestContext = async (t, makeSpace) => {
     'anyAddress',
   );
   const bridgeManager = await consume.bridgeManager;
+  /** @type {import('@agoric/vats').ScopedBridgeManager<'wallet'>} */
+  // @ts-expect-error XXX generics through EProxy
   const walletBridgeManager = await (bridgeManager &&
     E(bridgeManager).register(BridgeId.WALLET));
   const walletFactory = await E(zoe).startInstance(
diff --git a/packages/smart-wallet/test/supports.js b/packages/smart-wallet/test/supports.js
index 429be3242db..007c2ac39cf 100644
--- a/packages/smart-wallet/test/supports.js
+++ b/packages/smart-wallet/test/supports.js
@@ -63,9 +63,13 @@ export const subscriptionKey = subscription => {
 
 /** @returns {import('@agoric/vats').BridgeManager} */
 const makeFakeBridgeManager = () =>
+  // @ts-expect-error XXX generics puzzle: could be instantiated with a different subtype of constraint
   Far('fakeBridgeManager', {
     register(bridgeId, handler) {
       return Far('scopedBridgeManager', {
+        getBridgeId() {
+          return bridgeId;
+        },
         fromBridge(_obj) {
           assert.fail(`expected fromBridge`);
         },
diff --git a/packages/vats/src/core/basic-behaviors.js b/packages/vats/src/core/basic-behaviors.js
index 947b399bf21..a8592295d6c 100644
--- a/packages/vats/src/core/basic-behaviors.js
+++ b/packages/vats/src/core/basic-behaviors.js
@@ -659,6 +659,8 @@ export const addBankAssets = async ({
   const assetAdmin = E(agoricNamesAdmin).lookupAdmin('vbankAsset');
 
   const bridgeManager = await bridgeManagerP;
+  /** @type {import('../types.js').ScopedBridgeManager<'bank'> | undefined} */
+  // @ts-expect-error XXX EProxy
   const bankBridgeManager =
     bridgeManager && E(bridgeManager).register(BridgeId.BANK);
   const bankMgr = await E(E(loadCriticalVat)('bank')).makeBankManager(
diff --git a/packages/vats/src/core/chain-behaviors.js b/packages/vats/src/core/chain-behaviors.js
index f56b14b9f4f..48617e717b5 100644
--- a/packages/vats/src/core/chain-behaviors.js
+++ b/packages/vats/src/core/chain-behaviors.js
@@ -361,6 +361,8 @@ export const makeChainStorage = async ({
     return;
   }
 
+  /** @type {import('../types.js').ScopedBridgeManager<'storage'>} */
+  // @ts-expect-error XXX EProxy
   const storageBridgeManager = E(bridgeManager).register(BRIDGE_ID.STORAGE);
   storageBridgeManagerP.resolve(storageBridgeManager);
 
diff --git a/packages/vats/src/core/startWalletFactory.js b/packages/vats/src/core/startWalletFactory.js
index a2dd87df342..7a7a38eba94 100644
--- a/packages/vats/src/core/startWalletFactory.js
+++ b/packages/vats/src/core/startWalletFactory.js
@@ -70,8 +70,8 @@ const publishRevivableWalletState = async (
  *       >['creatorFacet'];
  *       adminFacet: AdminFacet;
  *     };
- *     walletBridgeManager: import('../types.js').ScopedBridgeManager;
- *     provisionWalletBridgeManager: import('../types.js').ScopedBridgeManager;
+ *     walletBridgeManager: import('../types.js').ScopedBridgeManager<'wallet'>;
+ *     provisionWalletBridgeManager: import('../types.js').ScopedBridgeManager<'provisionWallet'>;
  *   }>} powers
  * @param {{
  *   options?: {
diff --git a/packages/vats/src/core/types-ambient.d.ts b/packages/vats/src/core/types-ambient.d.ts
index 5d3daa5bc15..0cbf6bf7f4e 100644
--- a/packages/vats/src/core/types-ambient.d.ts
+++ b/packages/vats/src/core/types-ambient.d.ts
@@ -372,7 +372,9 @@ type ChainBootstrapSpaceT = {
   provisionWalletBridgeManager:
     | import('../types.js').ScopedBridgeManager
     | undefined;
-  storageBridgeManager: import('../types.js').ScopedBridgeManager | undefined;
+  storageBridgeManager:
+    | import('../types.js').ScopedBridgeManager<'storage'>
+    | undefined;
   /**
    * Convienence function for starting a contract (ungoverned) and saving its
    * facets (including adminFacet)
diff --git a/packages/vats/src/ibc.js b/packages/vats/src/ibc.js
index 334c264171a..e75e24afafc 100644
--- a/packages/vats/src/ibc.js
+++ b/packages/vats/src/ibc.js
@@ -814,7 +814,7 @@ export const prepareCallbacks = zone => {
   return zone.exoClass(
     'callbacks',
     undefined,
-    /** @param {ScopedBridgeManager} dibcBridgeManager */
+    /** @param {ScopedBridgeManager<'dibc'>} dibcBridgeManager */
     dibcBridgeManager => ({ dibcBridgeManager }),
     {
       /**
diff --git a/packages/vats/src/localchain.js b/packages/vats/src/localchain.js
index eb1a6c7845b..09294b9f0d0 100644
--- a/packages/vats/src/localchain.js
+++ b/packages/vats/src/localchain.js
@@ -13,14 +13,14 @@ const { Fail } = assert;
 
 /**
  * @typedef {{
- *   system: ScopedBridgeManager;
+ *   system: ScopedBridgeManager<'vlocalchain'>;
  *   bank: Bank;
  * }} AccountPowers
  */
 
 /**
  * @typedef {{
- *   system: ScopedBridgeManager;
+ *   system: ScopedBridgeManager<'vlocalchain'>;
  *   bankManager: BankManager;
  * }} LocalChainPowers
  */
diff --git a/packages/vats/src/proposals/localchain-proposal.js b/packages/vats/src/proposals/localchain-proposal.js
index c45c6de5403..3d640fdfbdc 100644
--- a/packages/vats/src/proposals/localchain-proposal.js
+++ b/packages/vats/src/proposals/localchain-proposal.js
@@ -6,7 +6,7 @@ import { BridgeId as BRIDGE_ID } from '@agoric/internal';
  * @param {BootstrapPowers & {
  *   consume: {
  *     loadCriticalVat: VatLoader<any>;
- *     localchainBridgeManager: import('../types').ScopedBridgeManager;
+ *     localchainBridgeManager: import('../types').ScopedBridgeManager<'vlocalchain'>;
  *   };
  *   produce: {
  *     localchain: Producer<any>;
@@ -51,9 +51,11 @@ export const setupLocalChainVat = async (
 
   localchainVat.reset();
   localchainVat.resolve(vats.localchain);
-  /** @type {import('../types').ScopedBridgeManager} */
+  /** @type {import('../types').ScopedBridgeManager<'vlocalchain'>} */
   let scopedManager;
   try {
+    /** @type {import('../types.js').ScopedBridgeManager<'vlocalchain'>} */
+    // @ts-expect-error XXX EProxy
     scopedManager = await E(bridgeManager).register(BRIDGE_ID.VLOCALCHAIN);
     localchainBridgeManager.reset();
     localchainBridgeManager.resolve(scopedManager);
diff --git a/packages/vats/src/proposals/network-proposal.js b/packages/vats/src/proposals/network-proposal.js
index 1972526d676..4691d9ebfc9 100644
--- a/packages/vats/src/proposals/network-proposal.js
+++ b/packages/vats/src/proposals/network-proposal.js
@@ -20,7 +20,7 @@ const NUM_IBC_PORTS_PER_CLIENT = 3;
 
 /**
  * @param {SoloVats | NetVats} vats
- * @param {ERef<import('../types.js').ScopedBridgeManager>} [dibcBridgeManager]
+ * @param {ERef<import('../types.js').ScopedBridgeManager<'dibc'>>} [dibcBridgeManager]
  */
 export const registerNetworkProtocols = async (vats, dibcBridgeManager) => {
   /** @type {Promise<void>[]} */
@@ -130,6 +130,8 @@ export const setupNetworkProtocols = async (
   const allocator = await portAllocatorP;
 
   const bridgeManager = await bridgeManagerP;
+  /** @type {import('../types.js').ScopedBridgeManager<'dibc'> | undefined} */
+  // @ts-expect-error XXX EProxy
   const dibcBridgeManager =
     bridgeManager && E(bridgeManager).register(BRIDGE_ID.DIBC);
 
diff --git a/packages/vats/src/types.d.ts b/packages/vats/src/types.d.ts
index f91b4ae577e..f364d8f0bd7 100644
--- a/packages/vats/src/types.d.ts
+++ b/packages/vats/src/types.d.ts
@@ -2,6 +2,7 @@ import type { Bytes } from '@agoric/network';
 import type { PromiseVow } from '@agoric/vow';
 import type { Guarded } from '@endo/exo';
 import type { ERef } from '@endo/far';
+import type { BridgeIdValue } from '@agoric/internal';
 
 export type Board = ReturnType<
   ReturnType<typeof import('./lib-board.js').prepareBoardKit>
@@ -96,7 +97,13 @@ export type BridgeHandler = {
 };
 
 /** An object which handles messages for a specific bridge */
-export type ScopedBridgeManager = Guarded<{
+export type ScopedBridgeManager<BridgeId extends BridgeIdValue> = Guarded<{
+  /**
+   * Optional bridge ID getter. Not part of the production bridge vat but
+   * available in fake bridges as a means for test reflection and for the type
+   * system to hang the bridgeId
+   */
+  getBridgeId?: () => BridgeId;
   toBridge: (obj: any) => Promise<any>;
   fromBridge: (obj: any) => PromiseVow<void>;
   initHandler: (handler: ERef<BridgeHandler>) => void;
@@ -105,10 +112,10 @@ export type ScopedBridgeManager = Guarded<{
 
 /** The object to manage this bridge */
 export type BridgeManager = {
-  register: (
-    bridgeId: string,
+  register: <BridgeId extends BridgeIdValue>(
+    bridgeId: BridgeId,
     handler?: ERef<BridgeHandler | undefined>,
-  ) => ScopedBridgeManager;
+  ) => ScopedBridgeManager<BridgeId>;
 };
 
 export type IBCPortID = string;
diff --git a/packages/vats/src/vat-bank.js b/packages/vats/src/vat-bank.js
index b6289458565..023233746c9 100644
--- a/packages/vats/src/vat-bank.js
+++ b/packages/vats/src/vat-bank.js
@@ -52,7 +52,7 @@ const BalanceUpdaterI = M.interface('BalanceUpdater', {
 
 /**
  * @typedef {Pick<
- *   import('./types.js').ScopedBridgeManager,
+ *   import('./types.js').ScopedBridgeManager<any>,
  *   'fromBridge' | 'toBridge'
  * >} BridgeChannel
  */
@@ -863,7 +863,9 @@ export function buildRootObject(_vatPowers, _args, baggage) {
 
   return Far('bankMaker', {
     /**
-     * @param {ERef<import('./types.js').ScopedBridgeManager | undefined>} [bankBridgeManagerP]
+     * @param {ERef<
+     *   import('./types.js').ScopedBridgeManager<'bank'> | undefined
+     * >} [bankBridgeManagerP]
      *   a bridge manager for the "remote" bank (such as on cosmos-sdk). If not
      *   supplied (such as on sim-chain), we just use local purses.
      * @param {ERef<{ update: import('./types.js').NameAdmin['update'] }>} [nameAdminP]
@@ -880,7 +882,7 @@ export function buildRootObject(_vatPowers, _args, baggage) {
         'denomToAddressUpdater',
       );
 
-      /** @param {ERef<import('./types.js').ScopedBridgeManager>} [bankBridgeMgr] */
+      /** @param {ERef<import('./types.js').ScopedBridgeManager<'bank'>>} [bankBridgeMgr] */
       async function getBankChannel(bankBridgeMgr) {
         // We do the logic here if the bridge manager is available.  Otherwise,
         // the bank is not "remote" (such as on sim-chain), so we just use
diff --git a/packages/vats/src/vat-bridge.js b/packages/vats/src/vat-bridge.js
index 1a5c00b3966..e18a80fea18 100644
--- a/packages/vats/src/vat-bridge.js
+++ b/packages/vats/src/vat-bridge.js
@@ -20,7 +20,7 @@ export function buildRootObject(vatPowers, _args, baggage) {
   );
 
   /**
-   * @param {ERef<import('./types.js').ScopedBridgeManager>} storageBridgeManagerP
+   * @param {ERef<import('./types.js').ScopedBridgeManager<'storage'>>} storageBridgeManagerP
    * @param {string} rootPath must be unique (caller responsibility to ensure)
    * @param {object} [options]
    */
diff --git a/packages/vats/test/localchain.test.js b/packages/vats/test/localchain.test.js
index 1ce3144b5af..b960aac08cd 100644
--- a/packages/vats/test/localchain.test.js
+++ b/packages/vats/test/localchain.test.js
@@ -1,14 +1,16 @@
 // @ts-check
 import { test as anyTest } from '@agoric/swingset-vat/tools/prepare-test-env-ava.js';
+
+import { AmountMath, AssetKind, makeIssuerKit } from '@agoric/ertp';
 import { reincarnate } from '@agoric/swingset-liveslots/tools/setup-vat-data.js';
+import { withAmountUtils } from '@agoric/zoe/tools/test-utils.js';
+import { makeDurableZone } from '@agoric/zone/durable.js';
 import { E } from '@endo/far';
-import { M } from '@endo/patterns';
 import { getInterfaceOf } from '@endo/marshal';
-import { makeDurableZone } from '@agoric/zone/durable.js';
-import { AmountMath, AssetKind, makeIssuerKit } from '@agoric/ertp';
-import { withAmountUtils } from '@agoric/zoe/tools/test-utils.js';
-import { buildRootObject as buildBankVatRoot } from '../src/vat-bank.js';
+import { M } from '@endo/patterns';
 import { prepareLocalChainTools } from '../src/localchain.js';
+import { buildRootObject as buildBankVatRoot } from '../src/vat-bank.js';
+import { makeFakeLocalchainBridge } from '../tools/fake-bridge.js';
 
 /**
  * @import {LocalChainAccount, LocalChainPowers} from '../src/localchain.js';
@@ -25,41 +27,10 @@ const provideBaggage = key => {
   return zone.mapStore(`${key} baggage`);
 };
 
-// TODO use testing facilities from #9396
-const makeTestContext = async t => {
-  const makeBridgeManager = async () => {
-    const zone = makeDurableZone(provideBaggage('mockBridgeManager'));
-    /** @type {undefined | ERef<BridgeHandler>} */
-    let bridgeHandler;
-
-    /** @type {ScopedBridgeManager} */
-    const bridgeManager = zone.exo('BridgeManager', undefined, {
-      async fromBridge(obj) {
-        t.is(typeof obj, 'string');
-      },
-      async toBridge(obj) {
-        switch (obj.type) {
-          case 'VLOCALCHAIN_ALLOCATE_ADDRESS': {
-            t.log('VLOCALCHAIN_ALLOCATE_ADDRESS', obj);
-            return 'agoricfoo';
-          }
-          default: {
-            t.is(obj, null);
-            return undefined;
-          }
-        }
-      },
-      initHandler(newHandler) {
-        bridgeHandler = newHandler;
-      },
-      setHandler(newHandler) {
-        bridgeHandler = newHandler;
-      },
-    });
-    return { bridgeManager, bridgeHandler };
-  };
-
-  const { bridgeManager } = await makeBridgeManager();
+const makeTestContext = async _t => {
+  const localchainBridge = makeFakeLocalchainBridge(
+    makeDurableZone(provideBaggage('localchain')),
+  );
 
   const makeBankManager = () => {
     const zone = makeDurableZone(provideBaggage('bank'));
@@ -81,7 +52,7 @@ const makeTestContext = async t => {
   };
 
   const localchain = await makeLocalChain({
-    system: bridgeManager,
+    system: localchainBridge,
     bankManager,
   });
 
@@ -123,7 +94,7 @@ test('localchain - deposit and withdraw', async t => {
         t.is(getInterfaceOf(lca), 'Alleged: LocalChainAccount');
 
         const address = await E(lca).getAddress();
-        t.is(address, 'agoricfoo');
+        t.is(address, 'agoric1fakeBridgeAddress');
         contractsLca = lca;
       },
       deposit: async () => {
diff --git a/packages/vats/test/network.test.js b/packages/vats/test/network.test.js
index 636de11ee78..326b9f05bcd 100644
--- a/packages/vats/test/network.test.js
+++ b/packages/vats/test/network.test.js
@@ -1,17 +1,18 @@
-import { test } from '@agoric/swingset-vat/tools/prepare-test-env-ava.js';
 import { reincarnate } from '@agoric/swingset-liveslots/tools/setup-vat-data.js';
+import { test } from '@agoric/swingset-vat/tools/prepare-test-env-ava.js';
 
-import { E } from '@endo/far';
 import {
   makePinnedHistoryTopic,
   prepareDurablePublishKit,
   subscribeEach,
 } from '@agoric/notifier';
-import { makeDurableZone } from '@agoric/zone/durable.js';
 import { prepareVowTools } from '@agoric/vow/vat.js';
+import { makeDurableZone } from '@agoric/zone/durable.js';
+import { E } from '@endo/far';
 
 import { buildRootObject as ibcBuildRootObject } from '../src/vat-ibc.js';
 import { buildRootObject as networkBuildRootObject } from '../src/vat-network.js';
+import { makeFakeIbcBridge } from '../tools/fake-bridge.js';
 
 import { registerNetworkProtocols } from '../src/proposals/network-proposal.js';
 
@@ -92,36 +93,18 @@ test('network - ibc', async t => {
   const pinnedHistoryTopic = makePinnedHistoryTopic(subscriber);
   const events = subscribeEach(pinnedHistoryTopic)[Symbol.asyncIterator]();
 
-  let hndlr;
-  /** @type {import('../src/types.js').ScopedBridgeManager} */
-  const bridgeHandler = zone.exo('IBC Bridge Manager', undefined, {
-    toBridge: async obj => {
-      const { method, type, ...params } = obj;
+  const ibcBridge = makeFakeIbcBridge(
+    zone,
+    obj => {
+      const { method, type: _, ...params } = obj;
       publisher.publish([method, params]);
-      t.is(type, 'IBC_METHOD');
-      if (method === 'sendPacket') {
-        const { packet } = params;
-        return { ...packet, sequence: '39' };
-      }
-      return undefined;
-    },
-    fromBridge: async obj => {
-      if (!hndlr) throw Error('no handler!');
-      await when(E(hndlr).fromBridge(obj));
-    },
-    initHandler: h => {
-      if (hndlr) throw Error('already init');
-      hndlr = h;
     },
-    setHandler: h => {
-      if (!hndlr) throw Error('must init first');
-      hndlr = h;
-    },
-  });
+    (target, obj) => when(E(target).fromBridge(obj)),
+  );
 
   await registerNetworkProtocols(
     { network: networkVat, ibc: ibcVat, provisioning: undefined },
-    bridgeHandler,
+    ibcBridge,
   );
 
   const portAllocator = await E(networkVat).getPortAllocator();
@@ -181,7 +164,7 @@ test('network - ibc', async t => {
       },
     ]);
 
-    await E(bridgeHandler).fromBridge({
+    await E(ibcBridge).fromBridge({
       event: 'channelOpenAck',
       portID: 'port-1',
       channelID: 'channel-1',
@@ -221,7 +204,7 @@ test('network - ibc', async t => {
       },
     ]);
 
-    await E(bridgeHandler).fromBridge({
+    await E(ibcBridge).fromBridge({
       event: 'acknowledgementPacket',
       packet: {
         data: 'c29tZS10cmFuc2Zlci1tZXNzYWdl',
@@ -242,7 +225,7 @@ test('network - ibc', async t => {
   await testIBCOutbound();
 
   const testIBCInbound = async () => {
-    await E(bridgeHandler).fromBridge({
+    await E(ibcBridge).fromBridge({
       event: 'channelOpenTry',
       channelID: 'channel-2',
       portID: 'port-1',
@@ -253,7 +236,7 @@ test('network - ibc', async t => {
       counterpartyVersion: 'bazo',
     });
 
-    await E(bridgeHandler).fromBridge({
+    await E(ibcBridge).fromBridge({
       event: 'channelOpenConfirm',
       portID: 'port-1',
       channelID: 'channel-2',
@@ -270,7 +253,7 @@ test('network - ibc', async t => {
       },
     ]);
 
-    await E(bridgeHandler).fromBridge({
+    await E(ibcBridge).fromBridge({
       event: 'receivePacket',
       packet: {
         data: 'aW5ib3VuZC1tc2c=',
diff --git a/packages/vats/test/vat-bank.test.js b/packages/vats/test/vat-bank.test.js
index 46502424180..c57ff95211e 100644
--- a/packages/vats/test/vat-bank.test.js
+++ b/packages/vats/test/vat-bank.test.js
@@ -27,13 +27,15 @@ test('provideAssetSubscription - MapStore insertion order preserved', async t =>
     );
 
     const forwardMap = zone.mapStore(`${name} forward map`);
-    handleToId.forEach((id, h) => forwardMap.init(h, id));
+    for (const [h, id] of handleToId.entries()) {
+      forwardMap.init(h, id);
+    }
     const forwardMapIds = [...forwardMap.values()];
 
     const reverseMap = zone.mapStore(`${name} reverse map`);
-    [...handleToId.entries()]
-      .reverse()
-      .forEach(([h, id]) => reverseMap.init(h, id));
+    for (const [h, id] of [...handleToId.entries()].reverse()) {
+      reverseMap.init(h, id);
+    }
     const reverseMapIds = [...reverseMap.values()];
 
     t.deepEqual(
@@ -59,7 +61,7 @@ test('communication', async t => {
   /** @type {undefined | ERef<import('../src/types.js').BridgeHandler>} */
   let bankHandler;
 
-  /** @type {import('../src/types.js').ScopedBridgeManager} */
+  /** @type {import('../src/types.js').ScopedBridgeManager<'bank'>} */
   const bankBridgeMgr = zone.exo('fakeBankBridgeManager', undefined, {
     async fromBridge(obj) {
       t.is(typeof obj, 'string');
diff --git a/packages/vats/tools/fake-bridge.js b/packages/vats/tools/fake-bridge.js
new file mode 100644
index 00000000000..be4d9afbf26
--- /dev/null
+++ b/packages/vats/tools/fake-bridge.js
@@ -0,0 +1,80 @@
+import { Fail } from '@agoric/assert';
+import assert from 'node:assert/strict';
+
+/** @import {ScopedBridgeManager} from '../src/types.js'; */
+
+/**
+ * @param {import('@agoric/zone').Zone} zone
+ * @param {(obj) => void} onToBridge
+ * @param {(handler, obj) => Promise<void>} onFromBridge
+ * @returns {ScopedBridgeManager<'dibc'>}
+ */
+export const makeFakeIbcBridge = (zone, onToBridge, onFromBridge) => {
+  let hndlr;
+  return zone.exo('Fake IBC Bridge Manager', undefined, {
+    getBridgeId: () => 'dibc',
+    toBridge: async obj => {
+      onToBridge(obj);
+      const { method, type, ...params } = obj;
+      assert.equal(type, 'IBC_METHOD');
+      if (method === 'sendPacket') {
+        const { packet } = params;
+        return { ...packet, sequence: '39' };
+      }
+      return undefined;
+    },
+    fromBridge: async obj => {
+      if (!hndlr) throw Error('no handler!');
+      await onFromBridge(hndlr, obj);
+    },
+    initHandler: h => {
+      if (hndlr) throw Error('already init');
+      hndlr = h;
+    },
+    setHandler: h => {
+      if (!hndlr) throw Error('must init first');
+      hndlr = h;
+    },
+  });
+};
+
+/**
+ * @param {import('@agoric/zone').Zone} zone
+ * @param {(obj) => void} [onToBridge]
+ * @param {(handler, obj) => ERef<void>} [onFromBridge]
+ * @returns {ScopedBridgeManager<'vlocalchain'>}
+ */
+export const makeFakeLocalchainBridge = (
+  zone,
+  onToBridge = () => {},
+  onFromBridge = () => {},
+) => {
+  let hndlr;
+  return zone.exo('Fake Localchain Bridge Manager', undefined, {
+    getBridgeId: () => 'vlocalchain',
+    toBridge: async obj => {
+      onToBridge(obj);
+      const { method, type, ...params } = obj;
+      console.info('toBridge', type, method, params);
+      switch (type) {
+        case 'VLOCALCHAIN_ALLOCATE_ADDRESS':
+          return 'agoric1fakeBridgeAddress';
+        default:
+          Fail`unknown type ${type}`;
+      }
+      return undefined;
+    },
+    fromBridge: async obj => {
+      if (!hndlr) throw Error('no handler!');
+      await onFromBridge(hndlr, obj);
+    },
+    initHandler: h => {
+      if (hndlr) throw Error('already init');
+      hndlr = h;
+    },
+    setHandler: h => {
+      if (!hndlr) throw Error('must init first');
+      hndlr = h;
+    },
+  });
+};