What Is a Composable CMS?
A composable CMS is a content management system designed to plug into a modern technology stack rather than dictate it. Instead of a monolithic platform that bundles a database, rendering layer, and admin UI into one locked system, a composable CMS separates content management from content delivery.
Content lives in a structured repository. Your frontend, your search layer, your personalization tools, your analytics stack: each piece is chosen independently and composed together. The CMS provides content via an API. Everything else is your call.
Cosmic is built exactly for this model.
Why Cosmic Is the Right Composable CMS
Truly API-First
Cosmic stores all content and delivers it exclusively through a REST API. There is no templating engine, no server-side rendering built into the platform, no proprietary routing. Your content is accessible from any environment, any language, any framework. You control how it is fetched, transformed, and rendered.
The official npm package wraps the REST API with TypeScript-first ergonomics. Install it, point it at your bucket, and start fetching content in minutes.
Flexible Content Modeling with 20+ Metafield Types
Composable architecture requires flexible data structures. Rigid schemas break as requirements evolve. Cosmic gives you 20+ metafield types to model content exactly the way your product needs it:
- Text, Textarea, Markdown, HTML — for all content formats
- Number, Date, Color, Select, Multi-select — for structured attributes
- File, Files — for media with built-in CDN delivery
- Object, Objects — for relationships and linked content
- Repeater, Parent — for nested and grouped data structures
- Switch, Radio, Checkboxes — for boolean and option fields
- JSON — for custom structured data
Add, rename, or restructure fields at any time. No migrations. No data loss. Your content model grows with your product.
Framework Agnostic, by Design
Cosmic works with every major JavaScript framework and meta-framework:
- Next.js — Full-stack React apps, SSR, and static generation
- React — SPAs and client-rendered applications
- Vue — Progressive web apps and component-driven UIs
- Nuxt — Vue-based SSR and static site generation
- Astro — Content-heavy sites with zero JS by default
- Remix — Full-stack React with nested routing
- Svelte — Lightweight, compiled frontends
- Gatsby — Static site generation and data sourcing
Your framework decision stays yours. Swap or upgrade your frontend without touching your content repository.
Cosmic SDK and MCP Server
Cosmic SDK: The official gives TypeScript and JavaScript developers a fully typed client for fetching, filtering, sorting, and paginating content. It handles authentication, error handling, and response shaping so you ship faster.
Cosmic MCP Server: The Model Context Protocol Server lets AI-powered development tools (Cursor, Claude, and other MCP clients) connect directly to your Cosmic bucket. Developers can query and manage content from within their AI coding environment, making CMS content a first-class citizen in modern AI-assisted development.
Cosmic AI Agents
Composable architecture is not just for your tech stack. Cosmic AI Agents bring composability to your content operations. Four specialized agent types:
- Team Agents — live in Slack, WhatsApp, and Telegram. Add an AI team member that creates and manages content through natural language.
- Content Agents — autonomously research topics, generate structured CMS objects, and publish or queue content for review.
- Code Agents — connect to your GitHub repo, build features, commit changes, and open PRs automatically.
- Computer Use Agents — automate browser tasks, record demos, and extract data visually.
Chain agents into multi-step Workflows. A single workflow can generate content, build a frontend feature, and test it, all without a human in the loop.
No Migrations. No Lock-in.
Composable means replaceable. Cosmic does not trap you. Your content is always accessible via the REST API in structured JSON. Export it, sync it, transform it. And because schema changes never require a migration script, your content model can evolve freely as your architecture does.
How Composable Architecture Works in Practice
Here is a typical composable stack with Cosmic at the content layer:
Each layer is independently chosen, upgraded, and replaced. Cosmic delivers content to all of them via a single REST API. When your frontend framework changes, your content stays exactly where it is.
Real Teams Using Cosmic in Composable Stacks
Teams across industries have chosen Cosmic as the content layer in their composable stacks:
- FINN (car subscription platform) uses Cosmic so their marketing team can update website content without engineering involvement: "Cosmic is: us never having to ask a developer to change anything on the backend of our website." — Maximilian Wuhr, Co-Founder
- Parque Explora (science museum) manages multilingual visitor content through Cosmic's API.
- Vuetify (open-source Vue component library) delivers developer documentation via Cosmic.
- Tripwire Interactive uses Cosmic for game content and marketing pages.
Pricing
Start free. Scale as your architecture grows. Additional users are $29/user/month.
- Free: $0/month — 1 Bucket, 2 Team members, 1,000 Objects
- Builder: $49/month — 2 Buckets, 3 Team members, 5,000 Objects
- Team: $299/month — 3 Buckets, 5 Team members, 20,000 Objects
- Business: $499/month — 5 Buckets, 10 Team members, 50,000 Objects
- Enterprise: Custom pricing
All plans include the REST API, JavaScript/TypeScript SDK, Cosmic AI, and full content modeling flexibility.
Start Building Your Composable Stack
Cosmic is trusted by development teams worldwide and backed by Y Combinator (W19). Start free and add Cosmic as the content layer in your composable architecture today.
