diff --git a/bin/broker-register.mjs b/bin/broker-register.mjs
index c587061..cc983b5 100755
--- a/bin/broker-register.mjs
+++ b/bin/broker-register.mjs
@@ -17,6 +17,7 @@ import os from "node:os";
 import path from "node:path";
 import readline from "node:readline";
 import { webcrypto } from "node:crypto";
+import { pathToFileURL } from "node:url";
 
 const { subtle } = webcrypto;
 
@@ -602,6 +603,27 @@ export async function runRegistration({
   };
 }
 
+export function isMainModule(moduleUrl = import.meta.url, argv1 = process.argv[1]) {
+  if (!argv1) return false;
+
+  let argvUrl = "";
+  let argvRealUrl = "";
+
+  try {
+    argvUrl = pathToFileURL(path.resolve(argv1)).href;
+  } catch {
+    argvUrl = "";
+  }
+
+  try {
+    argvRealUrl = pathToFileURL(fs.realpathSync(argv1)).href;
+  } catch {
+    argvRealUrl = "";
+  }
+
+  return moduleUrl === argvUrl || (argvRealUrl !== "" && moduleUrl === argvRealUrl);
+}
+
 export async function main(argv = process.argv.slice(2)) {
   const parsed = parseArgs(argv);
 
@@ -650,7 +672,7 @@ export async function main(argv = process.argv.slice(2)) {
   return 0;
 }
 
-if (import.meta.url === `file://${process.argv[1]}`) {
+if (isMainModule()) {
   main().catch((err) => {
     const message = err instanceof Error ? err.message : String(err);
     console.error(`❌ ${message}`);
diff --git a/bin/broker-register.test.mjs b/bin/broker-register.test.mjs
index d0972d2..09cfc00 100644
--- a/bin/broker-register.test.mjs
+++ b/bin/broker-register.test.mjs
@@ -1,6 +1,10 @@
 import test from "node:test";
 import assert from "node:assert/strict";
+import fs from "node:fs";
+import os from "node:os";
+import path from "node:path";
 import { createServer } from "node:http";
+import { pathToFileURL } from "node:url";
 import {
   parseArgs,
   normalizeBrokerUrl,
@@ -9,6 +13,7 @@ import {
   registerWithBroker,
   upsertEnvContent,
   runRegistration,
+  isMainModule,
 } from "./broker-register.mjs";
 
 const FIXTURE_SERVER_KEYS = {
@@ -53,6 +58,24 @@ test("parseArgs sets verbose=true for -v and --verbose", () => {
   assert.equal(long.verbose, true);
 });
 
+test("isMainModule handles symlink argv path", () => {
+  const tempDir = fs.mkdtempSync(path.join(os.tmpdir(), "broker-register-main-"));
+  const realFile = path.join(tempDir, "real.mjs");
+  const symlinkFile = path.join(tempDir, "link.mjs");
+
+  try {
+    fs.writeFileSync(realFile, "export default 1;\n", "utf8");
+    fs.symlinkSync(realFile, symlinkFile);
+
+    const moduleUrl = pathToFileURL(fs.realpathSync(realFile)).href;
+    assert.equal(isMainModule(moduleUrl, symlinkFile), true);
+  } finally {
+    try { fs.unlinkSync(symlinkFile); } catch {}
+    try { fs.unlinkSync(realFile); } catch {}
+    try { fs.rmdirSync(tempDir); } catch {}
+  }
+});
+
 test("parseArgs accepts registration token", () => {
   const parsed = parseArgs(["--registration-token", "token-123"]);
   assert.equal(parsed.registrationToken, "token-123");