Prompt to Production.
The AI Website Builder CMS.
NextBlock is the free, open-source AI website builder CMS for teams that want more than a prototype. Add Cortex AI to point Claude Code, Cursor, or Codex at your site over MCP, free for 30 days. You keep a live Next.js 16 and Supabase website with a visual editor your team owns on day two.
Up in 10 minutes. Free to start.
Try the whole stack for free.
The CMS is free forever. Cortex AI, an optional premium module that includes the MCP server, starts with a 30-day trial and no credit card. One click deploys to Vercel, and you are prompting your own site in ten minutes. You can also let Claude Code, Cursor, or Codex build it for you.
- ✓ CMS: free and open source, with unlimited pages, editors, and sites.
- ✓ Cortex AI: 30 days free, no credit card, then a license only if you keep it.
- ✓ Bring your own AI subscription. No token markup, ever.
Why an AI Website Builder CMS Beats Prototype Code.
Prompt builders like Lovable, Bolt, and v0 are great at a first draft. Then they hand you code you must host, patch, and rebuild for every copy change. NextBlock takes the same prompts and turns them into a website your whole team can run.
Prompt to CMS, Not Just Code.
External AI agents scaffold real layouts as typed blocks. Editors then tweak copy, images, and sections in a Notion-style editor. Nobody writes a prompt or touches code to change a headline.
Bring Your Own AI Subscription via MCP.
Connect Claude Code, Codex, Cursor, or VS Code straight to /api/mcp. You pay for the AI plan you already have, not a SaaS token markup. This is the Cortex AI layer: free for 30 days, no credit card.
Zero-Redeploy JSONB Architecture.
Generated blocks land in PostgreSQL as validated JSONB. Pages publish in seconds with 100/100 Lighthouse defaults and no rebuild.
Side by side
Prototype tools versus NextBlock.
Lovable, Bolt, and v0 compared on what happens after the first prompt.
| What you get | Lovable, Bolt, v0 | NextBlock |
|---|---|---|
| Day one | ✗Prototype code you host and patch yourself. | ✓A live Next.js 16 and Supabase website. |
| Editing after launch | ✗A new prompt or a pull request for every change. | ✓A Notion-style visual editor, no code needed. |
| Drafts and revisions | ✗Code history only, nothing for content. | ✓Live Drafts and one-click restore of any page. |
| Publishing | ✗Rebuild and redeploy. | ✓Instant, straight from PostgreSQL. |
| Translations and SEO | ✗Not built in. | ✓Linked translations for every page and SEO graded as you type. |
| AI costs | ✗Platform credits, bought from the tool. | ✓Your own subscription over MCP, no markup. |
| Price of the platform | ✗A monthly plan. | ✓Free and open source, forever. Premium modules are optional, each with a 30-day free trial. |
Free forever
The CMS costs nothing.
The AI website builder CMS is free and open source. Unlimited pages, editors, and sites, self-hosted or on Vercel, with no plan to outgrow.
Cortex AI: 30-day free trial
Try the AI layer, then decide.
Cortex AI is an optional premium module. It starts with a 30-day trial and no credit card, and it unlocks AI inside the editor plus the MCP server. Cancel by doing nothing.
No token markup
Your plan does the work.
Over MCP, Cortex AI runs on the AI plan you already pay for, through Claude Code, Codex, or Cursor. Inside the editor, it uses your own OpenRouter key, free models included. The license buys the connection, not the tokens.
Model Context Protocol
How the MCP Connection Works.
Cortex AI exposes your CMS as an MCP server at /api/mcp. Any agent that speaks the standard can read your schema and write pages. The server is part of the Cortex AI license, and the 30-day trial needs no credit card.
Three steps take you from a fresh deploy to published pages, in about ten minutes.
Rather let an agent do the install? Ask Claude Code or Cursor to build your site with NextBlock. The agent runs npx create-nextblock@latest my-site --non-interactive, which starts the site on Docker by default and writes the MCP config the agent needs. You create your admin account and start the free Cortex AI trial in the browser, then the agent builds your pages over MCP. Read the agent install guide.
Step 1
Deploy and start the trial.
One click to Vercel, then start the free Cortex AI trial from the welcome screen or Administration → Packages. Mint a scoped token and paste one config entry into Claude Code, Codex, Cursor, or VS Code.
Step 2
Prompt the layout.
Ask for a new page. The agent calls create_page_layout and the page is saved as a draft made of validated blocks.
Step 3
Edit and publish.
Editors refine the draft in the visual editor and hit publish. The page goes live from PostgreSQL with no redeploy.
For Writers and Editors
- Notion-style editor. Slash commands, drag and drop, and inline Cortex AI in every text block.
- Live Drafts. Stage AI output safely, then publish when it reads right.
- Revisions. Restore any version of a page or post with one click.
- Built-in SEO checks. Headings, keyphrases, readability, and metadata graded as you type.
For Developers
- Next.js 16 core. Server Components, a public content cache that clears the moment you publish, and long-lived CDN caching for images.
- Supabase backend. Postgres, auth, storage, and row-level security you can read.
- Typed block registry. Every block has a Zod schema, so AI output is validated before it renders.
- Open source. Self-host on Docker or deploy to Vercel in one click.
Built with Next.js, React, Supabase, Stripe, Tailwind, Tiptap, Vercel, and Nx.
Now Available — Premium Module
Turn Your CMS Into
a Full Storefront.
NextBlock™ Commerce turns your content site into a full online store. Sell products, take payments, handle taxes, and ship orders — all from the block editor you already use. Try it free for 30 days, no credit card.
∞
Currencies
2
Providers
Auto
Tax Sync
Everything You Need to Sell Online
NextBlock™ Commerce ships a complete online store toolkit so you can go from catalog to checkout with ease.
Multi-Currency
Daily FX rate sync, rounding modes, charm pricing, and automatic product price sync across unlimited currencies.
Tax Automation
Manual stacked tax rates (GST + PST) or fully automatic calculation via Stripe Tax — you choose.
Shipping Zones
Zone-based rate resolution with country and state matching, per-currency pricing, and free-shipping thresholds.
Stripe & Freemius Checkout
Stripe for physical products, Freemius for digital licensing — provider-aware checkout with inventory validation.
Inventory Tracking
Automatic quantity deduction on payment with resilient fallback paths and variant-level stock management.
Orders & Invoices
Full order lifecycle management, stable invoice numbering, printable documents, and exportable order reports.
Now Available — Cortex AI
The CMS Is Free.
Cortex AI Is the AI Upgrade.
The NextBlock CMS costs nothing and never will. Cortex AI is one of our premium modules, alongside Commerce Pro, and more may follow. It adds AI inside the editor and an MCP server outside it, so Claude Code, Codex, Cursor, and VS Code can build your site.
Try it free for 30 days with no credit card. You bring the AI subscription you already pay for. The license buys the connection, never the tokens. A read-only MCP token never even sees the write tools, and page edits are saved as revisions you can restore.
$0
The CMS, forever
30
Days of Cortex AI free, no card
0 %
Token markup
More Than a CMS. An Ecosystem.
NextBlock™ is built to grow with your business and help your team succeed.
Roadmap in motion
Commerce ships first, then the broader ecosystem grows around plugins, blocks, and partner-built modules.
Available now
NextBlock™ Commerce
Transform your site into a composable storefront with products, checkout, multi-currency pricing, tax automation, and commerce blocks that live beside your editorial content.
Build the future
Plugin and block marketplace
A planned community marketplace will give developers room to publish, sell, and distribute custom blocks, themes, integrations, and partner modules.
Join Our Community.
NextBlock™ is being built in the open. Star the repo, share feedback, and help define the future of performance-first content management.
Have Questions?
NextBlock™ partners with early adopters to co-build features, sponsor modules, and shape the product direction.