diff --git a/mocha/setup.ts b/mocha/setup.ts
index ded201904..d1d81c5a6 100644
--- a/mocha/setup.ts
+++ b/mocha/setup.ts
@@ -1,6 +1,16 @@
 import * as chai from "chai";
-import * as chaiAsPromised from "chai-as-promised";
-import * as nock from "nock";
+import * as chaiAsPromisedModule from "chai-as-promised";
+import * as nockModule from "nock";
+
+// Normalize CommonJS exports so ts-node (Node.js 20) and Node.js 22's strip-only loader
+// both receive callable modules without relying on esModuleInterop.
+type ChaiPlugin = Parameters<typeof chai.use>[0];
+type NockModule = typeof nockModule;
+
+const chaiAsPromisedExport = chaiAsPromisedModule as ChaiPlugin & { default?: ChaiPlugin };
+const chaiAsPromised = chaiAsPromisedExport.default ?? chaiAsPromisedExport;
+const nockExport = nockModule as NockModule & { default?: NockModule };
+const nock = nockExport.default ?? nockExport;
 
 chai.use(chaiAsPromised);
 
diff --git a/package-lock.json b/package-lock.json
index 9c6f62e3e..f865797b0 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -44,7 +44,6 @@
         "eslint-plugin-prettier": "^4.0.0",
         "firebase-admin": "^13.0.0",
         "genkit": "^1.0.0-rc.4",
-        "js-yaml": "^3.13.1",
         "jsdom": "^16.2.1",
         "jsonwebtoken": "^9.0.0",
         "jwk-to-pem": "^2.0.5",
@@ -60,6 +59,7 @@
         "sinon": "^9.2.4",
         "ts-node": "^10.4.0",
         "typescript": "^4.3.5",
+        "yaml": "^2.8.1",
         "yargs": "^15.3.1"
       },
       "engines": {
@@ -8558,6 +8558,19 @@
       "integrity": "sha512-ncTzHV7NvsQZkYe1DW7cbDLm0YpzHmZF5r/iyP3ZnQtMiJ+pjzisCiMNI+Sj+xQF5pXhSHxSB3uDbsBTzY/c2A==",
       "dev": true
     },
+    "node_modules/yaml": {
+      "version": "2.8.1",
+      "resolved": "https://registry.npmjs.org/yaml/-/yaml-2.8.1.tgz",
+      "integrity": "sha512-lcYcMxX2PO9XMGvAJkJ3OsNMw+/7FKes7/hgerGUYWIoWu5j/+YQqcZr5JnPZWzOsEBgMbSbiSTn/dv/69Mkpw==",
+      "dev": true,
+      "license": "ISC",
+      "bin": {
+        "yaml": "bin.mjs"
+      },
+      "engines": {
+        "node": ">= 14.6"
+      }
+    },
     "node_modules/yargs": {
       "version": "15.4.1",
       "resolved": "https://registry.npmjs.org/yargs/-/yargs-15.4.1.tgz",
diff --git a/package.json b/package.json
index a9ec85b6f..9b1a91b18 100644
--- a/package.json
+++ b/package.json
@@ -301,7 +301,6 @@
     "eslint-plugin-prettier": "^4.0.0",
     "firebase-admin": "^13.0.0",
     "genkit": "^1.0.0-rc.4",
-    "js-yaml": "^3.13.1",
     "jsdom": "^16.2.1",
     "jsonwebtoken": "^9.0.0",
     "jwk-to-pem": "^2.0.5",
@@ -317,6 +316,7 @@
     "sinon": "^9.2.4",
     "ts-node": "^10.4.0",
     "typescript": "^4.3.5",
+    "yaml": "^2.8.1",
     "yargs": "^15.3.1"
   },
   "peerDependencies": {
diff --git a/scripts/bin-test/mocha-setup.ts b/scripts/bin-test/mocha-setup.ts
index 21b3996d1..1fe5d2f95 100644
--- a/scripts/bin-test/mocha-setup.ts
+++ b/scripts/bin-test/mocha-setup.ts
@@ -1,4 +1,11 @@
 import * as chai from "chai";
-import * as chaiAsPromised from "chai-as-promised";
+import * as chaiAsPromisedModule from "chai-as-promised";
+
+// Match the runtime shim in mocha/setup.ts so bin tests work on Node.js 20 ts-node
+// and Node.js 22's strip-only TypeScript loader without enabling esModuleInterop.
+type ChaiPlugin = Parameters<typeof chai.use>[0];
+
+const chaiAsPromisedExport = chaiAsPromisedModule as ChaiPlugin & { default?: ChaiPlugin };
+const chaiAsPromised = chaiAsPromisedExport.default ?? chaiAsPromisedExport;
 
 chai.use(chaiAsPromised);
diff --git a/scripts/bin-test/test.ts b/scripts/bin-test/test.ts
index 616b50fb5..cacc0e27c 100644
--- a/scripts/bin-test/test.ts
+++ b/scripts/bin-test/test.ts
@@ -5,7 +5,7 @@ import * as fs from "fs/promises";
 import * as os from "os";
 
 import { expect } from "chai";
-import * as yaml from "js-yaml";
+import { parse as parseYaml } from "yaml";
 import fetch from "node-fetch";
 import * as portfinder from "portfinder";
 
@@ -177,7 +177,7 @@ async function runHttpDiscovery(modulePath: string): Promise<DiscoveryResult> {
     const body = await res.text();
 
     if (res.status === 200) {
-      const manifest = yaml.load(body) as Record<string, unknown>;
+      const manifest = parseYaml(body) as Record<string, unknown>;
       return { success: true, manifest };
     } else {
       return { success: false, error: body };
diff --git a/spec/common/config.spec.ts b/spec/common/config.spec.ts
index 0376c8105..004be249a 100644
--- a/spec/common/config.spec.ts
+++ b/spec/common/config.spec.ts
@@ -23,23 +23,23 @@
 import { expect } from "chai";
 import * as fs from "fs";
 import * as process from "process";
-import Sinon = require("sinon");
+import * as sinon from "sinon";
 
 import { firebaseConfig, resetCache } from "../../src/common/config";
 
 describe("firebaseConfig()", () => {
-  let readFileSync: Sinon.SinonStub;
-  let cwdStub: Sinon.SinonStub;
+  let readFileSync: sinon.SinonStub;
+  let cwdStub: sinon.SinonStub;
 
   before(() => {
-    readFileSync = Sinon.stub(fs, "readFileSync");
+    readFileSync = sinon.stub(fs, "readFileSync");
     readFileSync.throws("Unexpected call");
-    cwdStub = Sinon.stub(process, "cwd");
+    cwdStub = sinon.stub(process, "cwd");
     cwdStub.returns("/srv");
   });
 
   after(() => {
-    Sinon.verifyAndRestore();
+    sinon.verifyAndRestore();
   });
 
   afterEach(() => {
diff --git a/spec/v1/config.spec.ts b/spec/v1/config.spec.ts
index 67bd920db..97d7b6faa 100644
--- a/spec/v1/config.spec.ts
+++ b/spec/v1/config.spec.ts
@@ -23,23 +23,23 @@
 import { expect } from "chai";
 import * as fs from "fs";
 import * as process from "process";
-import Sinon = require("sinon");
+import * as sinon from "sinon";
 
 import { config, resetCache } from "../../src/v1/config";
 
 describe("config()", () => {
-  let readFileSync: Sinon.SinonStub;
-  let cwdStub: Sinon.SinonStub;
+  let readFileSync: sinon.SinonStub;
+  let cwdStub: sinon.SinonStub;
 
   before(() => {
-    readFileSync = Sinon.stub(fs, "readFileSync");
+    readFileSync = sinon.stub(fs, "readFileSync");
     readFileSync.throws("Unexpected call");
-    cwdStub = Sinon.stub(process, "cwd");
+    cwdStub = sinon.stub(process, "cwd");
     cwdStub.returns("/srv");
   });
 
   after(() => {
-    Sinon.verifyAndRestore();
+    sinon.verifyAndRestore();
   });
 
   afterEach(() => {