diff --git a/packages/ERTP/package.json b/packages/ERTP/package.json
index 1213cd9a937..ddd9d9497e8 100644
--- a/packages/ERTP/package.json
+++ b/packages/ERTP/package.json
@@ -17,7 +17,7 @@
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json"
+    "lint:types": "tsc -p jsconfig.json"
   },
   "repository": {
     "type": "git",
diff --git a/packages/SwingSet/package.json b/packages/SwingSet/package.json
index 2e07041c964..c7210a32c46 100644
--- a/packages/SwingSet/package.json
+++ b/packages/SwingSet/package.json
@@ -17,7 +17,7 @@
     "test:xs-worker": "ava test/workers/test-worker.js -m 'xs vat manager'",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "yarn lint:types&&yarn lint:eslint",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "devDependencies": {
diff --git a/packages/SwingSet/src/controller/controller.js b/packages/SwingSet/src/controller/controller.js
index 61a1b510147..b9c75bc4465 100644
--- a/packages/SwingSet/src/controller/controller.js
+++ b/packages/SwingSet/src/controller/controller.js
@@ -1,5 +1,6 @@
 // @ts-check
 /* global globalThis, WeakRef, FinalizationRegistry */
+/* eslint-disable @typescript-eslint/prefer-ts-expect-error -- https://github.com/Agoric/agoric-sdk/issues/4620 */
 
 import fs from 'fs';
 import path from 'path';
@@ -287,9 +288,9 @@ export async function makeSwingsetController(
   }
 
   const bundles = [
-    // @ts-expect-error assume lockdownBundle is set
+    // @ts-ignore assume lockdownBundle is set
     JSON.parse(kvStore.get('lockdownBundle')),
-    // @ts-expect-error assume supervisorBundle is set
+    // @ts-ignore assume supervisorBundle is set
     JSON.parse(kvStore.get('supervisorBundle')),
   ];
   const startXSnap = makeStartXSnap(bundles, {
diff --git a/packages/SwingSet/src/kernel/kernelSyscall.js b/packages/SwingSet/src/kernel/kernelSyscall.js
index be38932f05d..c4f039b2630 100644
--- a/packages/SwingSet/src/kernel/kernelSyscall.js
+++ b/packages/SwingSet/src/kernel/kernelSyscall.js
@@ -1,4 +1,5 @@
 // @ts-check
+/* eslint-disable @typescript-eslint/prefer-ts-expect-error -- https://github.com/Agoric/agoric-sdk/issues/4620 */
 
 import { assert, details as X } from '@agoric/assert';
 import { insistKernelType } from './parseKernelSlots.js';
@@ -207,8 +208,10 @@ export function makeKernelSyscallHandler(tools) {
       workingLowerBound = actualLowerBound;
       workingUpperBound = actualUpperBound;
       workingKeyIterator = kvStore.getKeys(startKey, actualUpperBound);
+      // @ts-ignore some resolution thinks this is undefined
       nextIter = workingKeyIterator.next();
       if (!nextIter.done && nextIter.value === actualPriorKey) {
+        // @ts-ignore some resolution thinks this is undefined
         nextIter = workingKeyIterator.next();
       }
     }
diff --git a/packages/SwingSet/src/kernel/state/kernelKeeper.js b/packages/SwingSet/src/kernel/state/kernelKeeper.js
index 917c599c3a9..7aae837e6c1 100644
--- a/packages/SwingSet/src/kernel/state/kernelKeeper.js
+++ b/packages/SwingSet/src/kernel/state/kernelKeeper.js
@@ -1,4 +1,5 @@
 // @ts-check
+/* eslint-disable @typescript-eslint/prefer-ts-expect-error -- https://github.com/Agoric/agoric-sdk/issues/4620 */
 import { Nat, isNat } from '@agoric/nat';
 import { assert, details as X } from '@agoric/assert';
 import { wrapStorage } from './storageWrapper.js';
@@ -199,7 +200,7 @@ export default function makeKernelKeeper(
    */
   function getRequired(key) {
     assert(kvStore.has(key), X`storage lacks required key ${key}`);
-    // @ts-expect-error already checked .has()
+    // @ts-ignore already checked .has()
     return kvStore.get(key);
   }
 
diff --git a/packages/cache/package.json b/packages/cache/package.json
index 0db06556cd1..0a0cbdd0580 100644
--- a/packages/cache/package.json
+++ b/packages/cache/package.json
@@ -12,7 +12,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint --ext .js,.ts ."
   },
   "keywords": [],
diff --git a/packages/casting/package.json b/packages/casting/package.json
index 95e9a632c52..569d6992db0 100644
--- a/packages/casting/package.json
+++ b/packages/casting/package.json
@@ -13,7 +13,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint --ext .js,.ts ."
   },
   "keywords": [],
diff --git a/packages/cosmic-swingset/package.json b/packages/cosmic-swingset/package.json
index 46f1ab81bfe..29b886f240c 100644
--- a/packages/cosmic-swingset/package.json
+++ b/packages/cosmic-swingset/package.json
@@ -15,7 +15,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "keywords": [],
diff --git a/packages/deploy-script-support/package.json b/packages/deploy-script-support/package.json
index c11e111f468..34ddfb7edb5 100644
--- a/packages/deploy-script-support/package.json
+++ b/packages/deploy-script-support/package.json
@@ -13,7 +13,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 5 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint": "run-s --continue-on-error lint:*"
   },
   "repository": {
diff --git a/packages/governance/package.json b/packages/governance/package.json
index 2076b759640..cc019123964 100644
--- a/packages/governance/package.json
+++ b/packages/governance/package.json
@@ -16,7 +16,7 @@
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json"
+    "lint:types": "tsc -p jsconfig.json"
   },
   "repository": {
     "type": "git",
diff --git a/packages/inter-protocol/package.json b/packages/inter-protocol/package.json
index ee8e7800177..62144c3f1fe 100644
--- a/packages/inter-protocol/package.json
+++ b/packages/inter-protocol/package.json
@@ -16,7 +16,7 @@
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 5 -p jsconfig.json"
+    "lint:types": "tsc -p jsconfig.json"
   },
   "repository": {
     "type": "git",
diff --git a/packages/internal/src/config.js b/packages/internal/src/config.js
index c3923390a10..044f18538af 100644
--- a/packages/internal/src/config.js
+++ b/packages/internal/src/config.js
@@ -2,8 +2,8 @@
 /** @file
  *
  * Some of this config info may make more sense in a particular package. However
- * due to the maxNodeModuleJsDepth hack and our general lax dependency graph,
- * sometimes rational placements cause type resolution errors.
+ * due to https://github.com/Agoric/agoric-sdk/issues/4620 and our lax package
+ * dependency graph, sometimes rational placements cause type resolution errors.
  *
  * So as a work-around some constants that need access from more than one package are placed here.
  */
diff --git a/packages/notifier/package.json b/packages/notifier/package.json
index 66885c38732..493c8d88d60 100644
--- a/packages/notifier/package.json
+++ b/packages/notifier/package.json
@@ -15,7 +15,7 @@
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json"
+    "lint:types": "tsc -p jsconfig.json"
   },
   "repository": {
     "type": "git",
diff --git a/packages/notifier/src/asyncIterableAdaptor.js b/packages/notifier/src/asyncIterableAdaptor.js
index 1b5081c711f..9fd119ae24e 100644
--- a/packages/notifier/src/asyncIterableAdaptor.js
+++ b/packages/notifier/src/asyncIterableAdaptor.js
@@ -80,6 +80,8 @@ export const makeAsyncIterableFromNotifier = notifierP => {
                 return harden({ value, done });
               });
           }
+          // xxx hint for type checker
+          assert(myIterationResultP);
           return myIterationResultP;
         },
       });
diff --git a/packages/notifier/src/storesub.js b/packages/notifier/src/storesub.js
index 75442f69480..46523f70904 100644
--- a/packages/notifier/src/storesub.js
+++ b/packages/notifier/src/storesub.js
@@ -136,7 +136,8 @@ export const makeStoredSubscription = (
   }
 
   /** @type {StoredSubscription<T>} */
-  // @ts-expect-error getStoreKey invalid, deprecated type
+  // eslint-disable-next-line -- different per package https://github.com/Agoric/agoric-sdk/issues/4620
+  // @ts-ignore getStoreKey type does not have `subscription`
   const storesub = Far('StoredSubscription', {
     getStoreKey: async () => {
       if (!storageNode) {
diff --git a/packages/notifier/test/prepare-test-env-ava.js b/packages/notifier/test/prepare-test-env-ava.js
index 892e975dbb6..9aa9db8e7cb 100644
--- a/packages/notifier/test/prepare-test-env-ava.js
+++ b/packages/notifier/test/prepare-test-env-ava.js
@@ -4,4 +4,6 @@ import '@endo/init';
 import { wrapTest } from '@endo/ses-ava';
 import rawTest from 'ava';
 
+// eslint-disable-next-line @typescript-eslint/prefer-ts-expect-error
+// @ts-ignore -- https://github.com/endojs/endo/issues/1235
 export const test = wrapTest(rawTest);
diff --git a/packages/notifier/test/test-publish-kit.js b/packages/notifier/test/test-publish-kit.js
index 67b503f9935..40742429c11 100644
--- a/packages/notifier/test/test-publish-kit.js
+++ b/packages/notifier/test/test-publish-kit.js
@@ -1,4 +1,5 @@
 // @ts-check
+/* eslint-disable @typescript-eslint/prefer-ts-expect-error -- https://github.com/Agoric/agoric-sdk/issues/4620 */
 
 import { test } from './prepare-test-env-ava.js';
 import {
@@ -124,13 +125,13 @@ test('makePublishKit', async t => {
     'failure should not be allowed after finalization',
   );
   await t.throwsAsync(
-    // @ts-expect-error known to be promise version of PublicationList
+    // @ts-ignore known to be promise version of PublicationList
     subFinal.tail,
     undefined,
     'tail promise of final result should be rejected',
   );
   await t.throwsAsync(
-    // @ts-expect-error known to be promise version of PublicationList
+    // @ts-ignore known to be promise version of PublicationList
     subscriber.subscribeAfter(subFinal.publishCount),
     undefined,
     'subscribeAfter(finalPublishCount) should be rejected',
@@ -179,13 +180,13 @@ test('makePublishKit - immediate finish', async t => {
     'failure should not be allowed after finalization',
   );
   await t.throwsAsync(
-    // @ts-expect-error known to be promise version of PublicationList
+    // @ts-ignore known to be promise version of PublicationList
     subFinal.tail,
     undefined,
     'tail promise of final result should be rejected',
   );
   await t.throwsAsync(
-    // @ts-expect-error known to be promise version of PublicationList
+    // @ts-ignore known to be promise version of PublicationList
     subscriber.subscribeAfter(subFinal.publishCount),
     undefined,
     'subscribeAfter(finalPublishCount) should be rejected',
@@ -336,7 +337,7 @@ test('subscribeAfter bounds checking', async t => {
     const repr =
       typeof badCount === 'string' ? JSON.stringify(badCount) : badCount;
     t.throws(
-      // @ts-expect-error deliberate invalid arguments for testing
+      // @ts-ignore deliberate invalid arguments for testing
       () => subscriber.subscribeAfter(badCount),
       undefined,
       `subscribeAfter should reject invalid publish count: ${typeof badCount} ${repr}`,
diff --git a/packages/pegasus/package.json b/packages/pegasus/package.json
index 0903944ef1b..d8732d01549 100644
--- a/packages/pegasus/package.json
+++ b/packages/pegasus/package.json
@@ -16,7 +16,7 @@
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json"
+    "lint:types": "tsc -p jsconfig.json"
   },
   "repository": {
     "type": "git",
diff --git a/packages/smart-wallet/package.json b/packages/smart-wallet/package.json
index 18056dd7ba6..db9e8a229a5 100644
--- a/packages/smart-wallet/package.json
+++ b/packages/smart-wallet/package.json
@@ -10,7 +10,7 @@
     "test:xs": "exit 0",
     "lint": "run-s --continue-on-error lint:*",
     "lint-fix": "yarn lint:eslint --fix",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "devDependencies": {
@@ -19,7 +19,6 @@
     "@agoric/deploy-script-support": "^0.9.4",
     "@agoric/inter-protocol": "^0.13.1",
     "@agoric/swingset-vat": "^0.30.2",
-    "@agoric/vats": "^0.11.0",
     "@agoric/wallet-backend": "^0.13.3",
     "@endo/captp": "^2.0.17",
     "@endo/init": "^0.5.51",
diff --git a/packages/smart-wallet/src/smartWallet.js b/packages/smart-wallet/src/smartWallet.js
index faadb540047..697a2eb7d81 100644
--- a/packages/smart-wallet/src/smartWallet.js
+++ b/packages/smart-wallet/src/smartWallet.js
@@ -462,7 +462,7 @@ const behavior = {
   self: {
     /**
      *
-     * @param {import('@endo/captp').CapData<string>} actionCapData of type BridgeAction
+     * @param {import('@endo/marshal').CapData<string>} actionCapData of type BridgeAction
      * @param {boolean} [canSpend=false]
      */
     handleBridgeAction(actionCapData, canSpend = false) {
diff --git a/packages/solo/package.json b/packages/solo/package.json
index 259308709d8..0e5fe2b7c65 100644
--- a/packages/solo/package.json
+++ b/packages/solo/package.json
@@ -15,7 +15,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "keywords": [],
diff --git a/packages/store/package.json b/packages/store/package.json
index 3f098babf17..5abd7e769b6 100644
--- a/packages/store/package.json
+++ b/packages/store/package.json
@@ -13,7 +13,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "repository": {
diff --git a/packages/store/src/patterns/interface-tools.js b/packages/store/src/patterns/interface-tools.js
index e58ea45b47d..effdd3ab05a 100644
--- a/packages/store/src/patterns/interface-tools.js
+++ b/packages/store/src/patterns/interface-tools.js
@@ -364,7 +364,7 @@ export const defineHeapFarClassKit = (
   const contextMapKit = objectMap(methodsKit, () => new WeakMap());
   const prototypeKit = objectMap(methodsKit, (methods, facetName) =>
     defendPrototype(
-      // eslint-disable-next-line @typescript-eslint/prefer-ts-expect-error -- different per package #4620
+      // eslint-disable-next-line @typescript-eslint/prefer-ts-expect-error -- different per package https://github.com/Agoric/agoric-sdk/issues/4620
       // @ts-ignore could be symbol
       `${tag} ${facetName}`,
       contextMapKit[facetName],
@@ -394,7 +394,7 @@ export const defineHeapFarClassKit = (
     }
     return facets;
   };
-  // eslint-disable-next-line @typescript-eslint/prefer-ts-expect-error -- different per package #4620
+  // eslint-disable-next-line @typescript-eslint/prefer-ts-expect-error -- different per package https://github.com/Agoric/agoric-sdk/issues/4620
   // @ts-ignore xxx
   return harden(makeInstanceKit);
 };
diff --git a/packages/swing-store/package.json b/packages/swing-store/package.json
index 2fbc2bdc8c9..9afe6b51be3 100644
--- a/packages/swing-store/package.json
+++ b/packages/swing-store/package.json
@@ -14,7 +14,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "dependencies": {
diff --git a/packages/telemetry/package.json b/packages/telemetry/package.json
index 8fcb5690369..e7e9640eb55 100644
--- a/packages/telemetry/package.json
+++ b/packages/telemetry/package.json
@@ -12,7 +12,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "bin": {
diff --git a/packages/ui-components/package.json b/packages/ui-components/package.json
index e63e3f8951b..9a3d1e11e78 100644
--- a/packages/ui-components/package.json
+++ b/packages/ui-components/package.json
@@ -27,7 +27,7 @@
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json"
+    "lint:types": "tsc -p jsconfig.json"
   },
   "eslintConfig": {
     "extends": [
diff --git a/packages/vats/package.json b/packages/vats/package.json
index dd961b8f210..85fb4581c7f 100644
--- a/packages/vats/package.json
+++ b/packages/vats/package.json
@@ -18,7 +18,7 @@
     "test:xs": "exit 0",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 5 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "keywords": [],
diff --git a/packages/wallet/api/package.json b/packages/wallet/api/package.json
index 97a250d4531..f518e59e084 100644
--- a/packages/wallet/api/package.json
+++ b/packages/wallet/api/package.json
@@ -10,7 +10,7 @@
     "test:xs": "exit 0",
     "lint": "run-s --continue-on-error lint:*",
     "lint-fix": "yarn lint:eslint --fix",
-    "lint:types": "tsc --maxNodeModuleJsDepth 3 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint ."
   },
   "devDependencies": {
diff --git a/packages/wallet/ui/endo-promise-kit.d.ts b/packages/wallet/ui/endo-promise-kit.d.ts
deleted file mode 100644
index 4c846fd1c44..00000000000
--- a/packages/wallet/ui/endo-promise-kit.d.ts
+++ /dev/null
@@ -1,53 +0,0 @@
-// XXX hack until https://github.com/Agoric/agoric-sdk/issues/4560
-// Generated from @agoric/ertp in a manual build
-declare module '@endo/promise-kit' {
-  /**
-   * A reified Promise
-   */
-  type PromiseKit<T> = {
-    resolve: (value: ERef<T>) => void;
-    reject: (reason: any) => void;
-    promise: Promise<T>;
-  };
-  /**
-   * PromiseRecord is deprecated in favor of PromiseKit.
-   */
-  type PromiseRecord<T> = PromiseKit<T>;
-  /**
-   * A reference of some kind for to an object of type T. It may be a direct
-   * reference to a local T. It may be a local presence for a remote T. It may
-   * be a promise for a local or remote T. Or it may even be a thenable
-   * (a promise-like non-promise with a "then" method) for a T.
-   */
-  type ERef<T> = T | PromiseLike<T>;
-
-  /**
-   * Determine if the argument is a Promise.
-   *
-   * @param {unknown} maybePromise The value to examine
-   * @returns {maybePromise is Promise} Whether it is a promise
-   */
-  function isPromise(maybePromise: unknown): maybePromise is Promise<any>;
-
-  /**
-   * makePromiseKit() builds a Promise object, and returns a record
-   * containing the promise itself, as well as separate facets for resolving
-   * and rejecting it.
-   *
-   * @template T
-   * @returns {import('./src/types.js').PromiseKit<T>}
-   */
-  function makePromiseKit<T>(): PromiseKit<T>;
-  /**
-   * Creates a Promise that is resolved or rejected when any of the provided Promises are resolved
-   * or rejected.
-   *
-   * Unlike `Promise.race` it cleans up after itself so a non-resolved value doesn't hold onto
-   * the result promise.
-   *
-   * @template T
-   * @param {Iterable<T>} values An iterable of Promises.
-   * @returns {Promise<Awaited<T>>} A new Promise.
-   */
-  function racePromises<T>(values: Iterable<T>): Promise<Awaited<T>>;
-}
diff --git a/packages/web-components/package.json b/packages/web-components/package.json
index 7d1e929de0e..02aff64111a 100644
--- a/packages/web-components/package.json
+++ b/packages/web-components/package.json
@@ -14,7 +14,7 @@
     "test:watch": "web-test-runner --watch",
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json",
+    "lint:types": "tsc -p jsconfig.json",
     "lint:eslint": "eslint . --ignore-path .gitignore",
     "analyze": "cem analyze --litelement",
     "start": "web-dev-server --port 8100"
diff --git a/packages/zoe/package.json b/packages/zoe/package.json
index 904a73993ee..c0e5246b281 100644
--- a/packages/zoe/package.json
+++ b/packages/zoe/package.json
@@ -21,7 +21,7 @@
     "lint-fix": "yarn lint:eslint --fix",
     "lint": "run-s --continue-on-error lint:*",
     "lint:eslint": "eslint .",
-    "lint:types": "tsc --maxNodeModuleJsDepth 4 -p jsconfig.json"
+    "lint:types": "tsc -p jsconfig.json"
   },
   "repository": {
     "type": "git",
diff --git a/packages/zoe/src/contractSupport/priceAuthority.js b/packages/zoe/src/contractSupport/priceAuthority.js
index ff7614f9124..28e27f52299 100644
--- a/packages/zoe/src/contractSupport/priceAuthority.js
+++ b/packages/zoe/src/contractSupport/priceAuthority.js
@@ -1,4 +1,5 @@
 // @ts-check
+/// <reference path="../../../SwingSet/src/vats/timer/types.d.ts" />
 
 import { E } from '@endo/eventual-send';
 import { Far } from '@endo/marshal';
diff --git a/packages/zoe/src/contracts/priceAggregator.js b/packages/zoe/src/contracts/priceAggregator.js
index 1faa799568a..8182ca58caf 100644
--- a/packages/zoe/src/contracts/priceAggregator.js
+++ b/packages/zoe/src/contracts/priceAggregator.js
@@ -1,4 +1,5 @@
 // @ts-check
+/// <reference path="../../../SwingSet/src/vats/timer/types.d.ts" />
 
 import { makeIssuerKit, AssetKind, AmountMath } from '@agoric/ertp';
 import { E } from '@endo/eventual-send';