diff --git a/package-lock.json b/package-lock.json
index 54735bee0..fc7024485 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -42,7 +42,6 @@
         "mysql": "^2.18.1",
         "nodemailer": "^6.7.3",
         "nodemailer-smtp-transport": "^2.7.4",
-        "once": "^1.4.0",
         "progress-stream": "^2.0.0",
         "qrcode": "^1.5.0",
         "readdirp": "^3.6.0",
diff --git a/package.json b/package.json
index 8be3ca97c..0bf5f15fa 100644
--- a/package.json
+++ b/package.json
@@ -45,7 +45,6 @@
     "mysql": "^2.18.1",
     "nodemailer": "^6.7.3",
     "nodemailer-smtp-transport": "^2.7.4",
-    "once": "^1.4.0",
     "progress-stream": "^2.0.0",
     "qrcode": "^1.5.0",
     "readdirp": "^3.6.0",
diff --git a/src/apps.js b/src/apps.js
index b47131a0b..ff7edb5d8 100644
--- a/src/apps.js
+++ b/src/apps.js
@@ -157,7 +157,7 @@ const appstore = require('./appstore.js'),
     mail = require('./mail.js'),
     manifestFormat = require('cloudron-manifestformat'),
     mounts = require('./mounts.js'),
-    once = require('once'),
+    once = require('./once.js'),
     os = require('os'),
     path = require('path'),
     paths = require('./paths.js'),
diff --git a/src/backuptask.js b/src/backuptask.js
index 69eb4271b..010b797c2 100644
--- a/src/backuptask.js
+++ b/src/backuptask.js
@@ -28,7 +28,7 @@ const apps = require('./apps.js'),
     database = require('./database.js'),
     debug = require('debug')('box:backuptask'),
     fs = require('fs'),
-    once = require('once'),
+    once = require('./once.js'),
     path = require('path'),
     paths = require('./paths.js'),
     progressStream = require('progress-stream'),
diff --git a/src/externalldap.js b/src/externalldap.js
index c90fa0129..f779b8d54 100644
--- a/src/externalldap.js
+++ b/src/externalldap.js
@@ -20,7 +20,7 @@ const assert = require('assert'),
     debug = require('debug')('box:externalldap'),
     groups = require('./groups.js'),
     ldap = require('ldapjs'),
-    once = require('once'),
+    once = require('./once.js'),
     safe = require('safetydance'),
     settings = require('./settings.js'),
     tasks = require('./tasks.js'),
diff --git a/src/once.js b/src/once.js
new file mode 100644
index 000000000..190b0f369
--- /dev/null
+++ b/src/once.js
@@ -0,0 +1,14 @@
+'use strict';
+
+exports = module.exports = once;
+
+// https://github.com/isaacs/once/blob/main/LICENSE (ISC)
+function once (fn) {
+    const f = function () {
+        if (f.called) return f.value;
+        f.called = true;
+        return f.value = fn.apply(this, arguments);
+    };
+    f.called = false;
+    return f;
+}
diff --git a/src/shell.js b/src/shell.js
index fd60c204c..b1cc85192 100644
--- a/src/shell.js
+++ b/src/shell.js
@@ -4,7 +4,7 @@ const assert = require('assert'),
     BoxError = require('./boxerror.js'),
     child_process = require('child_process'),
     debug = require('debug')('box:shell'),
-    once = require('once'),
+    once = require('./once.js'),
     util = require('util');
 
 exports = module.exports = {