Rendering the green field.

subspaces.si

Free AI coding IDE

A coding IDE paid for by ads.

subspaces.si is Code - OSS in the browser. The opencode agent edits the file. A sponsored card under the reply keeps the Flash tokens free. No Pro tier.

Downloads coming soon.

Demo

Watch it edit a file.

Recorded in subspaces.si. A prompt in the chat, an opencode edit to listInvoices, and the sponsored card under the reply.

How it works

Four steps. Then the file changes.

  1. 01

    Watch an ad, unlock tokens

    The reply is a cheap Flash model. A sponsored card under it is what pays for those tokens. The ledger slows at 15 million tokens. It does not sell an upgrade.

  2. 02

    A real editor, via code-server

    The shell is Code - OSS, branded subspaces.si. It opens a small invoicing API so you can edit in the browser immediately.

  3. 03

    The opencode agent edits the file

    Ask it to change src/routes/invoices.ts. The harness reads the file and applies the edit in the workspace.

  4. 04

    A Gravity card sits under the reply

    The sponsored unit stays below the answer. Another can fill the explorer. Empty fill renders nothing when a live key is set.

The product

Free on purpose.

No subscription

There is no Pro tier and no frontier-model upsell. The bet is steady chat paid for by ads.

Code - OSS shell

code-server v4.141.0, named subspaces.si. The same editor you already know, opened on a sample API.

Flash only

Default model glm-5.3-flash, fallback deepseek-v4.1-flash. The proxy strips code, paths, and secrets before any ad request.

Sponsored card

A white card under the reply, and a slot in the explorer. Test mode is the default until you opt into production.

15M soft cap

The in-memory ledger counts tokens and slows replies at the cap. It does not block, and it does not ask you to pay.

One command

Unpack the archive and run ./start. Node.js 22 downloads the pinned opencode binary. Secrets stay in a gitignored .env.

FAQ

Short answers.

Is it really free?

Yes for the person using it. Ads and a sponsored theme are meant to cover a Flash model. There is nothing to subscribe to.

Where do the downloads come from?

From a public GitHub Release, not from this page's host. The buttons use VITE_DOWNLOAD_BASE_URL. Until that is set, this page shows the waitlist instead of a broken link.

Does any of this bill me?

The archives are not stored on Vercel Blob or a paid CDN. Public GitHub Release bandwidth is free. The demo video on this page stays under 10 MB so static hosting stays small. Do not attach a spending limit or a paid runner.

What runs in the browser versus on my machine?

This marketing page is static. The editor, code-server, and opencode serve run from the archive you download, or from pnpm dev locally.

What is the ad?

A Gravity unit under the assistant reply. Without a key, a local card fills the slot. With a key, an empty response renders nothing.