For site owners
A Website Your Team Runs
Pages, articles, search, forms and email, managed from a simple admin area. After setup, nobody needs to touch code.
Arc CMS for websites
Free & Open Source. MIT Licensed
The Open-Source Foundation for Websites and Apps You Own
Launch a fast website your team can manage, or start your next product with sign-in, email, payments and an admin area already built. It all runs on your own Firebase.
- MIT licensed
- 8,000+ automated tests
- 100+ pages of docs
- Your data, your Firebase
Proudly supported by
One Codebase, Three Ways to Use It
Start with a website and grow it into an app later. The custom space is in every copy, empty until you need it.
For developers and founders
The Foundation for Your Next App
Sign-in, roles, email, payments, an installable app and an admin area on day one. Your code lives apart from Arc CMS, so updates merge cleanly.
Arc CMS as an app foundationFor existing Firebase apps
A Backend for the App You Have
Install it next to your app as its admin area, content store and email engine, and email your app's users as a live audience.
Share a Firebase projectWebsites That Are Fast, Secure and Easy to Manage
A developer sets it up once. After that, your team writes, publishes and updates everything from the admin area.
Fast by Default
Every page is published as plain HTML and served from Google's global CDN. Nothing is rebuilt on each visit.
Secure by Design
No plugins to install or patch, and no server of your own to keep updated. Security rules and server-side checks guard your data.
Everything Built In
SEO, site search, multiple languages, forms, email and analytics come with it. No plugin bills, no plugin conflicts.
Easy to Manage
Content types with the fields you need, drafts, version history, a media library, and an admin area that works on a phone.
A Clean Editor With a Safety Net
Write in a clean editor with headings, tables, images, video and FAQ blocks. Drafts save themselves, and every publish is kept so you can restore an earlier version.
Content Shaped Like Your Business
Articles, services, team, events: give each its own fields, from 18 types including galleries, maps and FAQs. Import entries from a spreadsheet.
A Media Library That Does the Work
Images are resized and converted to WebP on upload. Crop to any ratio, pull pictures straight out of a PDF, and keep documents in the same library.
Every Language You Need
Publish in as many languages as you need. Each page gets its own address, the right search-engine tags and a language switcher.
One entry, every language
- English
/articles/opening-hours - Hindi
/hi/articles/opening-hours - French
/fr/articles/opening-hours
Each language gets its own address, search-engine tags and a switcher.
Turn Visitors Into Contacts
Signup and contact forms on any page, with emailed verification codes. Every sign-up becomes a contact you can tag, list and email.
Email Your Audience From the Admin
Branded newsletters, scheduled broadcasts and drip sequences from the admin, with one-click unsubscribe and consent tracking built in.
Built to Be Found by Google and Cited by AI
Every publish writes what search engines and AI assistants look for, so your pages are easy to find, understand and quote.
-
Structured Data on Every Page
Schema.org data for articles, products, events, FAQs, how-tos, breadcrumbs and your organisation, written for you.
-
Made for AI Readers
/llms.txt,/llms-full.txtand a Markdown copy of every page, so AI tools read your content cleanly. -
You Decide Who Crawls
Allow AI search and answer bots and block AI training bots, with a switch for each crawler.
-
Indexed Fast
A sitemap, RSS feeds, and IndexNow pings to Bing (which feeds ChatGPT search and Copilot) on every publish.
-
A Score Before You Publish
The editor's Checks tab rates each draft out of 100 and tells you exactly what to fix.
-
See Your AI Visitors
With Google Analytics connected, the dashboard counts visits from ChatGPT, Perplexity, Gemini, Claude and more.
The Foundation for Your Next App
Copy Arc CMS and start where most projects end. Sign-in, users, email, payments and an admin area are there on day one, so you write only what makes your app yours.
Ready on Day One
Sign-in
Email and password, Google, and phone with a PIN, on one page. Password resets never leave your app.
Users and Roles
Roles travel in signed claims, checked by security rules and server functions.
Payments
One-time and subscription checkout through Dodo Payments, with Stripe and PhonePe coming soon. Plans, credits and premium-only pages.
Email Engine
Transactional and marketing email through Gmail, SMTP or Resend, with logs and one-click unsubscribe.
Admin Area
Users, content, audience, email, media and settings, ready for your team. Add your own screens to its menu.
Member Area
A signed-in home for your users, with profile, billing and account deletion.
Installable App
An installable PWA with icons, offline start and an update prompt, switched on in one line.
Content and Search
Content types, media, site search and SEO for your product's marketing pages.
Your Code Stays Yours
Your app lives in its own custom space, which Arc CMS never touches. Pull every update with a git
merge, and npm run check:core confirms you never edited core.
Switch off a feature your app doesn't use, such as payments or SMS, and it's gone: no menu, no page, no server function.
// src/custom/features.ts
export const CUSTOM_FEATURES: FeatureChoice = {
off: ['sms', 'payments'],
on: ['pwa'],
};- Angular 21
- Firebase
- TypeScript
- TipTap
- Vite
- Vitest
8,000+ automated tests · 100+ pages of docs
Everything Built In
25 capabilities in one install, maintained together. No plugins to buy, update or keep compatible.
Content Types
Your own types and fields, drafts, version history and spreadsheet import.
Rich Editor
Tables, video, FAQ and how-to blocks, with drafts that save themselves.
Media Library
Automatic WebP sizes, cropping, images from PDFs, documents and free stock photos.
SEO and AI Discoverability
Structured data, sitemap, llms.txt and IndexNow on every publish.
Site Search
Type-ahead search that forgives typos and accents, with no outside service.
Languages
As many site languages as you need, and an admin area in English and Hindi.
Forms
Signup and contact forms with emailed codes and spam checks.
Audience
One contact per person, with lists, tags, consent and CSV import.
Email Marketing
Broadcasts, drip sequences and announcements from the admin.
Automations
When something happens, send an email, post an in-app notification, or add someone to a list.
Sign-in and Members
Email and password, Google, or phone with a PIN, plus a member area.
Payments
Checkout, subscriptions, credits and premium access through Dodo Payments, with Stripe and PhonePe coming soon.
Also built in: an analytics dashboard, notifications, a feedback button with voice notes, banners and a cookie notice, data import and export, an installable app, and an admin that works on a phone. Switch off the features you don't need, such as payments, SMS or email marketing, in one file.
How Arc CMS Compares
An honest look, including where the others are the better choice.
| Feature | Arc CMS | WordPress | Webflow | Ghost |
|---|---|---|---|---|
| Software cost | Free (MIT) | Free (GPL) | Free Starter plan; paid from $15/month per site, plus seats | Free (MIT), or Ghost(Pro) from $15/month |
| Where it runs | Your own Firebase project | Any PHP and MySQL host | Webflow's hosting only | Your server, or Ghost(Pro) |
| Pages served as | Static HTML on a CDN | Built by PHP on each visit, unless you add caching | Webflow's CDN | A Node app, or Ghost(Pro) |
| Your own content types | Built in | Custom post types (code or plugins) | CMS collections | Posts and pages |
| Multiple languages | Built in | Plugin (WPML from €99/year, or Polylang) | Add-on, $9 to $29 per language per month | One install per language, or Weglot |
| Email marketing | Built in: lists, broadcasts, drips, automations | Plugin (MailPoet) or Mailchimp | Not built in | Newsletters built in (self-hosted needs Mailgun) |
| Members and payments | Built in: Dodo Payments; Stripe and PhonePe coming soon | Plugins (WooCommerce, membership plugins) | Ecommerce from $29/month; memberships retired January 2026 | Members and Stripe subscriptions built in |
| Setup | A developer sets it up | One-click installs at many hosts | Visual builder, no code needed | Easiest on Ghost(Pro) |
Plugins are where WordPress risk lives: Patchstack's 2026 report found 91% of the 11,334 new WordPress vulnerabilities of 2025 in plugins, and 6 in core.
Where the others win: Webflow's visual builder needs no developer. WordPress has
the largest ecosystem. Ghost is the simplest choice for a newsletter.
| Feature | Arc CMS | ShipFast | Supastarter | MakerKit |
|---|---|---|---|---|
| Price | Free (MIT) | $199 to $249 one-time | $349 to $1,499 one-time | $299 to $599 one-time (Lite is free) |
| Stack | Angular 21, Firebase | Next.js, MongoDB or Supabase | Next.js, Nuxt or TanStack | Next.js, React Router or TanStack, Supabase |
| Admin area | Full admin | Not listed | Superadmin | Super Admin |
| Website and CMS | Full CMS, static pages, SEO, llms.txt | Blog and SEO helpers | MDX blog and docs | Blog and docs |
| Email marketing | Lists, broadcasts, drips, automations | Transactional email | Transactional email | Transactional email |
| Sign-in | Email and password, Google, phone with PIN | Google, magic links | Passkeys, OAuth, 2FA, magic links | Supabase or Better Auth |
| Teams and organisations | Not yet (admin and user roles) | Not listed | Yes | Yes |
| Payments | Dodo Payments; Stripe and PhonePe coming soon | Stripe, Lemon Squeezy | Stripe, Lemon Squeezy, Polar, Creem, Dodo | Stripe, Lemon Squeezy, Paddle |
Where the others win: a starter kit fits better if you need teams and organisations,
Stripe, or a React and Next.js stack.
Prices and features as of October 2026, from each vendor's website.
Your Site. Your Data. Your Control.
No vendor lock-in, no licence fees, and no one who can raise your price or switch you off.
Your Data
Stored in your own Firebase project. Export your content, contacts and media at any time.
Your Infrastructure
Google's Firebase, in the region you choose, on your own billing account.
Updates Without Breakage
Pull new versions with a git merge. Your own code and site files never conflict, and 8,000+ tests guard every release.
Firebase's pay-as-you-go Blaze plan is required. You pay Google only for what you use, and small sites often stay within its free allowances.
Deploy once. Own it for good.
Get Started
Pick your path. The docs walk you through every step.
Build a Website
Install it, define your content types, add your templates and publish.
Docs: Build a websiteStart an App
Copy the repository, switch off what you don't need, and add your own screens and functions.
Docs: Build a custom appAdd It to Your App
Install it next to your Firebase app as its admin, content and email backend.
Docs: Share a Firebase projectHave Us Build It
Tell us what you need. We design, build and deploy it on your Firebase, then hand it over.
Send a build requestYou'll need a Firebase project on the Blaze plan, Node 22.18 or later, and the Firebase CLI.
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Frequently Asked Questions
Everything you need to know before getting started.
Yes. It's MIT licensed: use it, change it, even sell what you build. There are no licence fees. You pay Google for Firebase usage on the Blaze plan, and small sites often stay within the free allowances.
Teams who want a fast website they can run themselves, and developers who want a head start on an app with sign-in, email, payments and an admin area already built.
For the setup and your page templates, yes, or we can build it for you. After that, your team works entirely in the admin area, with no code.
Pages are published as static HTML, there are no plugins to patch, and SEO, forms, email and languages are built in. WordPress has a bigger ecosystem and one-click hosting. See the comparison above.
Yes. The docs walk through converting an existing HTML site step by step, and you can import entries from a spreadsheet.
Your site keeps running. It lives in your own Firebase project, and the code is MIT licensed and yours to keep.
Yes. Firebase Hosting connects custom domains with free SSL certificates.
Your data stays in your own Firebase project, protected by security rules and server-side checks, and roles are carried in signed claims. There are no third-party plugins.
Your site can publish in any language. The admin area is in English and Hindi. Emails are currently English only.
Read the docs, ask in GitHub Discussions, or have us build it for you.
Get in Touch
Questions, partnerships, or just want to say hi? We'd love to hear from you.
Have Us Build It
Want a website or an app on Arc CMS without doing the setup yourself? Tell us what you need.
- Custom template design
- Deploy Arc CMS for you
- Add custom features
- Firebase configuration
- One-on-one guidance
Community Support
Technical questions or feature requests?
- Report bugs and issues
- Request new features
- Follow development on GitHub
- Contribute to open source
- Share templates and designs
- Get help from other users
- Access documentation
- Join developer discussions
Business Enquiries
For media enquiries, partnership opportunities, or sponsorship discussions.
- Media & press coverage
- Partnership opportunities
- Sponsorship discussions
- Enterprise support
- White-label solutions
- Integration partnerships
- Speaking engagements
- Investment enquiries
Connect
Follow our journey, ask questions, or just say hi on your favourite platform.