Mail coding is vibe coding by email
Mail coding is vibe coding done over email. You write what you want in a mail, an AI builds it, and the result comes back to your inbox with a link. You reply with what to change, and the next version comes back the same way. There is no chat window to keep open and no app to learn; your mailbox is the whole workflow.
The term is ours. Vibe coding is building software by describing it and judging the result instead of reading the code. Mail coding keeps that loop exactly as it is and moves it to the one tool every business owner already lives in.
Why we built it
Mail coding started as an internal project of the OpenKBS dev team. The question was: what is the simplest possible way to get a website or an app built? The answer was already in everyone's pocket: email.
Everyone knows how email works, so there is nothing to learn. You send the request and get on with your day; the answer waits with your unread mail instead of you waiting for it.
That is the point for a founder: no sitting in front of a chat window watching text appear. Write what you need, do something else, read the answer when you get to it.
Why email
A chat window asks you to be there. You open it, you type, you wait, you watch. That suits developers, who sit in front of a screen anyway. It does not suit the owner of a furniture shop who thinks of the missing inquiry form while loading a van.
Email is asynchronous by nature. You write when it occurs to you, from a phone, and the answer waits for you. Nobody has to teach you the interface. Each topic is a thread, so the shop catalogue and the new invoice design never get mixed up, and the whole history of a project sits in your mailbox, searchable, next to the rest of your correspondence. Forward a mail to a colleague and they know the state of the project without logging in anywhere.
Email also forces a useful discipline on the machine. An answer that has to read well in a mail client is short, says what was done, where to see it, and what it needs from you. That is a better report than a scrolling log of tool calls.
How mail coding works at OpenKBS
There are two ways in. Write to ai@openkbs.com with what you want built, or describe it on the mail coding page. Either way you get one reply with a sign-up link, and your text is already waiting on the registration page as the first task. Create the account, and the AI Studio starts on it immediately. You can close the tab.
The first working version arrives by email, usually within minutes: a link to the site or app, and a temporary test login if there is one. Reply to that email with what to change, and the change comes back the same way.
A few details that make this work in practice:
- Every chat has its own address. A reply always lands in the right conversation. When you want a separate topic, ask for a new chat and the next mail comes from a new address, which is a new thread in your mailbox.
- The Studio is one click away. Every mail links to the same chat in the OpenKBS Studio, with the files, the preview and the history. Write there or by email, whichever is closer; the answer follows the channel you used last.
- Questions come as numbered options. When the AI needs a decision, it asks in text, one question at a time, and you answer with a number or a sentence. Nothing requires clicking a button inside an app.
- Domains and money need a yes. The AI can connect a domain you already own, sending you the name-server records to set at your hosting company, or register a new one. A purchase is always quoted first, with the price in credits, and nothing is bought until you reply yes.
Several threads, one project
Every chat in a project has its own email address, and every mail thread in your inbox is one chat. Write to the project's address and a new chat opens on a new topic. So a big project is not one endless conversation. The product catalogue is one thread, invoicing another, the design a third, each with its own history, each a separate chat in the Studio if you ever open it. You pick up whichever thread is on your mind and the others wait.
This is what makes something so plain able to carry something as large as an ERP. Say a wholesaler wants their own system. The first mail describes the business and gets a working skeleton back. Then the modules grow in parallel threads. One thread for stock, where the warehouse manager replies with the counting sheets. One for invoicing, where the accountant replies with the rules. One for orders, one for suppliers, one for reports. Each thread is a chat with its own memory, and all of them work on the same code and the same database. The agent can also open a new thread itself when a topic deserves one, and mail you its address. Three months later the inbox holds the full history of a system nobody sat down to "program".
The interface stays as simple as it was on day one. The power is in how many of these conversations can run side by side, and in the fact that the people who know each part of the business can answer in the thread about their part, from their own mailbox, with no training.
Your own address
You can run all of this from an address on your own domain, say ai@yourcompany.com. If your domain already has mail, with Google Workspace or Microsoft 365, add a forwarding rule from that address to your project's address at reply.openkbs.com, the way any alias is set up, and you are done. Mails from the owner reach the project, replies come back into the same thread. For domains hosted at OpenKBS with no mail elsewhere, we are adding the receiving side so the address works without a forward.
Attachments
Files you attach to a mail land in the project exactly as if you had uploaded them in the Studio, in its uploads folder, and the agent works with them in that same reply. A logo, a spreadsheet of products, a PDF with the old spec, a screenshot of what looks wrong. Send it, say what to do with it, done.
A worked example
A small furniture shop runs on WordPress and is tired of plugins. The owner writes to ai@openkbs.com: move the site to you, keep the colours, add a product catalogue and an inquiry form.
Ten minutes after sign-up the first mail arrives: the shop is online on a preview address, 42 products in a catalogue, an inquiry form that emails the owner, the same green and oak palette. A test login for the admin page is in the mail, marked temporary.
The owner replies: connect the domain, and make the inquiry form ask for a phone number. The next mail has the two name-server records to set at the registrar and confirms the form change. A week later, from a phone, between deliveries: add a sale badge to the oak tables. Done, with a link.
That is the whole project. Three threads in a mailbox, no developer, no plugin updates, and a site the owner can keep changing by writing a sentence.
Limits and price
Honesty about the edges matters more here than anywhere, because the person on the other end is not watching a screen.
Anything that needs you to click inside an application, such as approving a payment or connecting a third-party account with a login, cannot happen by mail. In those cases the mail tells you exactly where to go and what to do, and the link takes you there.
Replies are accepted only from the address you registered with. A mail from another address, or one that fails the usual email authentication checks, is ignored without an answer. That is what keeps a stranger from writing to your project.
The AI's work is paid in credits. The first project starts free; after that you see the price of what you ask for, and a mail arrives if credits run out, with a link to add more. Nothing is charged for the emails themselves.
Mail coding is not a different product from the OpenKBS Studio. It is the same agent, the same project, the same code, reached through the tool you already open fifty times a day. If that sounds like the way you would rather build, start on the mail coding page or just write to ai@openkbs.com.