All your tools in one place. Pick up where you left off.
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Click any product below to open it directly. Think Tank is your primary workspace.
Your business workspace. Step-by-step templates, structured pages, depth levels. Write business plans, validate ideas, plan products with guided frameworks.
Open SynapseFile and asset manager. Upload, organize, preview files. Grid and list views, folders, drag-drop. Your digital filing cabinet, sorted and searchable.
Open SprintCoding IDE powered by AI. Browse repos, view code with syntax highlighting, watch the AI build in real-time. Direct-apply governed execution.
Open BuildYour AI operating partner. Validate ideas, plan businesses, build products, and run your entire operation through conversation. Learns how you work. Gets sharper every session.
Open SymbioteFitness coaching platform. Workout program builder, client management, progress tracking, messaging. Built on FCOS — live and deployable.
Native app — Windows, macOS, Linux. Specialist Agent Network workspace with 8 colour-coded agents, + launcher, and localStorage session persistence.
DownloadFive steps. One system. Zero guesswork.
Define what you're building and why it matters. Use Synapse templates to structure your thinking. Identify your customer, your market, and your unfair advantage before writing a single line of code.
Test your idea against real data. Customer research, market sizing, competition analysis, and financial modelling. Kill bad ideas fast and double down on the ones worth building.
Break the build into phases. Map dependencies, set milestones, create realistic timelines. FCOS turns strategy into an actionable execution plan with clear deliverables.
AI writes the code. Direct-apply, governed execution, build sessions. Watch it happen in real-time inside FCOS Build. From component to full-stack application in hours, not weeks.
Deploy to production. HTML products served instantly through the FCOS platform. Iterate based on real user feedback. Launch, learn, repeat.
FCOS Omni is the demo suite — 20 fully populated, production-ready apps built entirely on the FCOS platform. Real data. Real interfaces. The platform apps below (Build, Workspace, Synapse, Sprint, Brainz) run FCOS itself.
Every FCOS product is built on a shared design system. No frameworks, no build tools, no npm. Pure HTML, CSS, and JavaScript.
Core design tokens, typography, cards, buttons, forms, tables
Reactive state, data binding, routing, toast notifications, event bus
Dropdowns, datepicker, tabs, carousel, stepper, tooltips, data tables
Entrance animations, stagger delays, hover effects, keyframes
Hero sections, pricing grids, FAQ, testimonials, timeline, footer
53 inline SVG icons as CSS mask-image classes. Zero HTTP requests
Bar charts, line charts, donut charts, sparklines, all in pure CSS
Dark/light mode toggle, brand color customization, localStorage persistence
Spacing, sizing, gradients, glassmorphism, glow effects, responsive text
Print-optimized styles. Clean output for invoices, reports, certificates
Client-side form validation, error states, real-time field checking
Drag-and-drop, sortable lists, resize handles, context menus
Symbiote AI layer — message routing, mode detection, system prompt injection, counselling mode
GPT ship layer — read, batch-deploy, and Playwright-verify any app directly from a ChatGPT conversation. No copy-paste.
Intelligence and execution, working together seamlessly.
The intelligence layer. Reasoning, planning, validation, and decision-making. FCOS orchestrates the AI — structuring your context, managing your history, and routing the right intelligence to the right tool at the right moment. You bring the key. We do everything else.
The execution layer. 290 operations across 14 systems. Synapse manages knowledge. Sprint handles files. Build writes production code. Precision enforces quality. Every product is connected to a shared execution engine — auth, billing, templates, telemetry — all in one.
FCOS is not another tool. It is a thinking system, an execution engine, and a builder platform — all in one. We believe founders should spend their time on decisions, not configuration. On strategy, not setup. On shipping, not switching tabs.
Every plan includes AI-powered tools built specifically for founders.
Free forever. No credit card required.
Everything you need to validate and build.
The full operating system for serious builders.
Everything you need to know about FCOS.
FCOS (Founder Clarity Operating System) is an all-in-one platform built for founders, solopreneurs, and indie builders. It combines business planning, file management, AI-powered coding, and strategic thinking into a single system. If you are building a product or business from scratch, FCOS is designed for you.
Yes. FCOS is model-agnostic — connect any supported AI model with your own API key. Your conversations go directly to the model and never touch our servers. You control the intelligence. We provide the operating system: the structure, the execution layer, the 290 operations, and everything that makes the AI actually useful for building a business.
FCOS Omni is a suite of 20 fully populated, production-ready applications built entirely on the FCOS platform — dashboards, CRM, kanban, analytics, helpdesk, HR, accounting, chat, email, and more. Every one uses real sample data and the FCOS design system. They are not mockups — they are real apps you can fork, customise, and ship. FCOS Build can generate, extend, and deploy any Omni app in a single session.
FCOS is both no-code and full-code. Synapse lets you plan and structure without writing code. Build IDE lets you watch AI write production code in real-time. You can use FCOS without touching code, or dive deep into the source. The 225+ templates include standard, premium, and full app replacers — all real HTML/CSS/JS that you own and control.
Other tools give you a workspace. FCOS gives you an operating system. Every product — Synapse, Sprint, Build, Symbiote — is built on the same shared execution engine, design system, and AI layer. There is no switching tabs, no stitching tools together, no losing context. One system takes you from first idea to shipped product.
Absolutely. The free tier includes Synapse with 3 pages, Sprint with 100MB storage, 20 starter templates, and limited Symbiote access. It is a genuine free tier, not a trial. Upgrade to Pro or Enterprise when you need more capacity, templates, and features.
Get started with FCOS today. Free forever, upgrade when you are ready.
No credit card required. Free tier includes Synapse + Sprint + Symbiote.