diff --git a/src/index.ts b/src/index.ts
index d0e3228..6de892f 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -3,6 +3,7 @@ import { execSync } from "node:child_process"
 import { readFileSync } from "node:fs"
 import { homedir } from "node:os"
 import { join } from "node:path"
+import { LSOF_LISTEN_RE } from "./lsof.js"
 import {
   notify,
   setStatus,
@@ -16,8 +17,6 @@ import {
   type SplitDirection,
 } from "./cmux.js"
 
-export const LSOF_LISTEN_RE = /:(\d+)\s+\(LISTEN\)/
-
 const plugin: Plugin = async ({ client, $ }) => {
   const pendingPermissions = new Set<string>()
   const pendingQuestions = new Set<string>()
diff --git a/src/lsof.ts b/src/lsof.ts
new file mode 100644
index 0000000..2145516
--- /dev/null
+++ b/src/lsof.ts
@@ -0,0 +1 @@
+export const LSOF_LISTEN_RE = /:(\d+)\s+\(LISTEN\)/
\ No newline at end of file
diff --git a/test/lsof-parse.test.ts b/test/lsof-parse.test.ts
index e0979b9..e026671 100644
--- a/test/lsof-parse.test.ts
+++ b/test/lsof-parse.test.ts
@@ -1,5 +1,5 @@
 import { test, expect } from "bun:test"
-import { LSOF_LISTEN_RE } from "../src/index"
+import { LSOF_LISTEN_RE } from "../src/lsof"
 
 test("LSOF_LISTEN_RE captures the port from a real lsof line", () => {
   const line =
diff --git a/test/plugin-export.test.ts b/test/plugin-export.test.ts
new file mode 100644
index 0000000..7e8f5b4
--- /dev/null
+++ b/test/plugin-export.test.ts
@@ -0,0 +1,27 @@
+import { test, expect } from "bun:test"
+import { existsSync } from "node:fs"
+import { execFileSync } from "node:child_process"
+import plugin from "../src/index"
+import * as pluginModule from "../src/index"
+
+async function loadBuiltPluginModule() {
+  const builtPluginPath = new URL("../dist/index.js", import.meta.url)
+
+  if (!existsSync(builtPluginPath)) {
+    execFileSync("bun", ["run", "build"], { stdio: "inherit" })
+  }
+
+  return import("../dist/index.js")
+}
+
+test("public plugin module only exposes a default function export", () => {
+  expect(typeof plugin).toBe("function")
+  expect(Object.keys(pluginModule)).toEqual(["default"])
+})
+
+test("built plugin module only exposes a default function export", async () => {
+  const builtPluginModule = await loadBuiltPluginModule()
+
+  expect(typeof builtPluginModule.default).toBe("function")
+  expect(Object.keys(builtPluginModule)).toEqual(["default"])
+})
\ No newline at end of file