You type who can open it
Share your localhost
with anyone you want
Your app runs on your computer and nowhere else. Arithm puts it online and lets in only the people you name.
One email when it is ready. Nothing else.
Works with whatever you already build in
- Next.js
- Vite
- React
- Astro
- SvelteKit
- Remix
- Nuxt
The whole idea
Put what you built online, let in only who you choose and nobody else.
Everyone sees only their own
- Priya₹84,000
- Dan₹42,500
- Sam₹18,000
Priya cannot see Dan's. Dan cannot see Sam's.
0
passwords for anyone to create or remember
1
command between your laptop and a real URL
How you do it
Three things, once.
Put it online
Run one command in the folder your app lives in. That is the whole setup.
Type their emails
Only the people you list can get in. Everyone else who finds the link is turned away.
They open the link
They type their email, get a six digit code, and they are in. No password. No account to create.
Compared to what you use today
Each one does part of it.
These are all good tools. Every one leaves at least one piece for you to work out, and the fourth row is the one nobody does.
| Capability | Arithm | ngrok | Vercel | Cloudflare Access | Replit |
|---|---|---|---|---|---|
| Puts your app on the internet | Yes | No | Yes | Yes | Yes |
| Only the people you name can open it | Yes | No | No | Yes | No |
| Nobody has to create a password | Yes | Not applicable | No | Yes | No |
| Each person sees only their own data | Yes | No | No | No | No |
| Nothing to configure | Yes | Yes | No | No | Yes |
ngrok points at the computer on your desk, so it stops the moment you close the lid. Replit does most of this, but only for apps you build inside Replit. Cloudflare Access locks a door beautifully and knows nothing about what is behind it.
What you do not need
None of the hard parts.
This is the list that normally stops people, and the reason most apps built with AI never leave the laptop they were made on.
- A domain name to buy
- A database to set up
- Passwords for anyone to remember
- Google settings to fill in
- A single line of code about logins
- Any idea how any of it works
It is not live yet.
Being built in the open. Leave your email and I will tell you the day you can use it.