diff --git a/src/server/dev.ts b/src/server/dev.ts
index 8a40e92da..176f6b08f 100644
--- a/src/server/dev.ts
+++ b/src/server/dev.ts
@@ -14,13 +14,14 @@ import EventEmitter from 'events'
 import { backend } from './feat/backend'
 import { startExpressServer } from './feat/express'
 import { setUp as setUpEmails } from './feat/emails'
+import { URL } from 'url'
 
 const omnibus = new EventEmitter()
 
 const app = backend({
   omnibus,
   cookieSecret: process.env.COOKIE_SECRET ?? v4(),
-  origin: process.env.CLIENT_URL || 'http://localhost:8080',
+  origin: new URL(process.env.CLIENT_URL || 'http://localhost:8080'),
 })
 
 startExpressServer(app)
diff --git a/src/server/feat/backend.ts b/src/server/feat/backend.ts
index 8880e8904..cf2bee3c7 100644
--- a/src/server/feat/backend.ts
+++ b/src/server/feat/backend.ts
@@ -5,6 +5,7 @@ import cors from 'cors'
 import EventEmitter from 'events'
 import express, { Express } from 'express'
 import passport from 'passport'
+import { URL } from 'url'
 import { cookieAuthStrategy } from '../../authenticateRequest'
 import login from '../../routes/login'
 import getProfile from '../../routes/me'
@@ -22,7 +23,7 @@ export const backend = ({
   origin,
 }: {
   omnibus: EventEmitter
-  origin: string
+  origin: URL
   cookieSecret: string
 }): Express => {
   const app = express()
@@ -36,7 +37,7 @@ export const backend = ({
 
   app.use(
     cors({
-      origin,
+      origin: `${origin.protocol}//${origin.host}`,
       credentials: true,
     }),
   )
diff --git a/src/server/prod.ts b/src/server/prod.ts
index c25ba3fa3..7e1368b12 100644
--- a/src/server/prod.ts
+++ b/src/server/prod.ts
@@ -12,6 +12,7 @@ import EventEmitter from 'events'
 import { backend } from './feat/backend'
 import { startExpressServer } from './feat/express'
 import { setUp as setUpEmails } from './feat/emails'
+import { URL } from 'url'
 
 const omnibus = new EventEmitter()
 
@@ -21,9 +22,15 @@ if (cookieSecret === undefined || cookieSecret.length === 0) {
   cookieSecret = v4()
 }
 
-const origin = process.env.ORIGIN
-if (origin === undefined || !/^http/.test(origin)) {
-  console.error(`Must set ORIGIN!`)
+let origin: URL
+try {
+  origin = new URL(process.env.ORIGIN ?? '')
+} catch (err) {
+  console.error(
+    `Must set ORIGIN, current value is not a URL: "${process.env.ORIGIN}": ${
+      (err as Error).message
+    }!`,
+  )
   process.exit(1)
 }