diff --git a/.github/workflows/node-ci.yml b/.github/workflows/node-ci.yml
index c7a1e08e..dae5a90e 100644
--- a/.github/workflows/node-ci.yml
+++ b/.github/workflows/node-ci.yml
@@ -90,7 +90,7 @@ jobs:
           TMP: ${{ steps.windows-temp.outputs.path || runner.temp }}
           TMPDIR: ${{ steps.windows-temp.outputs.path || runner.temp }}
           CODEX_SECURITY_ALLOW_MACHINE_POLICY_TEST: ${{ runner.environment == 'github-hosted' && runner.os == 'Windows' && 'true' || 'false' }}
-        run: pnpm --dir sdk/typescript run test
+        run: pnpm --dir sdk/typescript run ${{ runner.os == 'Windows' && 'test:windows' || 'test' }}
 
       - name: Check formatting
         run: pnpm --dir sdk/typescript run format
diff --git a/sdk/typescript/package.json b/sdk/typescript/package.json
index d99211ed..f23bf08b 100644
--- a/sdk/typescript/package.json
+++ b/sdk/typescript/package.json
@@ -49,6 +49,7 @@
     "lint": "tsc --noEmit",
     "prepack": "node --run build",
     "test": "bun test --timeout 30000 ./tests-ts",
+    "test:windows": "node scripts/run-windows-tests.mjs",
     "test:package": "node scripts/smoke-package.mjs",
     "types": "pnpm run generate:models:check && tsc --noEmit"
   },
diff --git a/sdk/typescript/scripts/run-windows-tests.mjs b/sdk/typescript/scripts/run-windows-tests.mjs
new file mode 100644
index 00000000..8f87a082
--- /dev/null
+++ b/sdk/typescript/scripts/run-windows-tests.mjs
@@ -0,0 +1,79 @@
+import { spawn } from "node:child_process";
+import { readdir, stat } from "node:fs/promises";
+import { join } from "node:path";
+import { fileURLToPath } from "node:url";
+
+const testDirectory = fileURLToPath(new URL("../tests-ts/", import.meta.url));
+const testFiles = (
+  await Promise.all(
+    (await readdir(testDirectory))
+      .filter((name) => name.endsWith(".test.ts"))
+      .map(async (name) => ({
+        name,
+        size: (await stat(join(testDirectory, name))).size,
+      })),
+  )
+).sort(
+  (left, right) =>
+    right.size - left.size || left.name.localeCompare(right.name),
+);
+const configuredWorkers = Number.parseInt(
+  process.env["CODEX_SECURITY_WINDOWS_TEST_WORKERS"] ?? "4",
+  10,
+);
+if (!Number.isSafeInteger(configuredWorkers) || configuredWorkers < 1) {
+  throw new Error("CODEX_SECURITY_WINDOWS_TEST_WORKERS must be positive");
+}
+const workerCount = Math.min(configuredWorkers, testFiles.length);
+const groups = Array.from({ length: workerCount }, () => ({
+  files: [],
+  size: 0,
+}));
+for (const testFile of testFiles) {
+  const group = groups.reduce((smallest, candidate) =>
+    candidate.size < smallest.size ? candidate : smallest,
+  );
+  group.files.push(testFile.name);
+  group.size += testFile.size;
+}
+const preload = process.env["CODEX_SECURITY_TEST_PRELOAD"];
+const running = new Set();
+let failed = false;
+let interrupted = false;
+
+const stop = () => {
+  interrupted = true;
+  for (const child of running) child.kill();
+};
+process.once("SIGINT", stop);
+process.once("SIGTERM", stop);
+
+const runTestGroup = (files) =>
+  new Promise((resolve) => {
+    const argumentsList = ["test", "--timeout", "30000"];
+    if (preload !== undefined) argumentsList.push("--preload", preload);
+    argumentsList.push(...files.map((file) => join(testDirectory, file)));
+    const child = spawn("bun", argumentsList, {
+      stdio: "inherit",
+      windowsHide: true,
+    });
+    running.add(child);
+    child.once("error", (error) => {
+      running.delete(child);
+      console.error(`Could not start test worker: ${error.message}`);
+      resolve(false);
+    });
+    child.once("close", (code, signal) => {
+      running.delete(child);
+      resolve(code === 0 && signal === null);
+    });
+  });
+
+console.error(
+  `Running ${testFiles.length} Windows test files with ${workerCount} workers.`,
+);
+const results = await Promise.all(
+  groups.map(({ files }) => runTestGroup(files)),
+);
+failed = results.some((passed) => !passed);
+if (failed || interrupted) process.exitCode = 1;
diff --git a/sdk/typescript/tests-ts/skeleton.test.ts b/sdk/typescript/tests-ts/skeleton.test.ts
index 128ec67b..8d9277ec 100644
--- a/sdk/typescript/tests-ts/skeleton.test.ts
+++ b/sdk/typescript/tests-ts/skeleton.test.ts
@@ -82,7 +82,12 @@ describe("TypeScript package skeleton", () => {
     expect(packageJson.scripts.test).toBe(
       "bun test --timeout 30000 ./tests-ts",
     );
-    expect(ciWorkflow).toContain("run: pnpm --dir sdk/typescript run test\n");
+    expect(packageJson.scripts["test:windows"]).toBe(
+      "node scripts/run-windows-tests.mjs",
+    );
+    expect(ciWorkflow).toContain(
+      "run: pnpm --dir sdk/typescript run ${{ runner.os == 'Windows' && 'test:windows' || 'test' }}\n",
+    );
     expect(ciWorkflow).not.toContain("--timeout 60000");
   });