Describe a system, choose the level of detail, and generate an editable architecture you can explore and refine.
High-level architecture and core components.
Use one of these prompts or write your own.
Explore common architectures without using AI.
Practise HLD and LLD design for system design interviews. Describe a system, get an editable high-level design, then open any service’s LLD view to see its internal components and dependencies, plus its data model where the design includes one. Diagrams are conceptual, based on public patterns. Your prompt, and an architecture image if you upload one, is sent to an AI provider; the editor runs in your browser.
From a one-line prompt to an editable diagram:
Yes — that is a core use case. Alongside the diagram you get a structured Design Brief (functional and non-functional requirements, scale assumptions with worked estimates, data flows, deep dives, trade-offs and failure scenarios) and a conversational interviewer that asks questions grounded in your current design and gives feedback. You can also open it directly from a Mock Interview system-design round.
High-Level Design is the system view: the major components — clients, gateways, services, caches, queues, databases — and how requests flow between them. In this tool the HLD level shows the whole architecture and its boundaries; you can open any service from there to see its service-level and low-level design.
Low-Level Design is the implementation view of a single service — its internal steps, data model and dependencies. Select a service and open the LLD level to see how it works internally, derived from the same source-of-truth architecture graph (never a separate copy).
No. Every diagram is a conceptual architecture based on publicly known patterns and general information — not any organisation’s actual internal system. Components carry an evidence label (documented, common pattern, inferred, assumption) so you can see what is well-grounded and what is a reasonable guess.
You describe a system (e.g. “Design a scalable URL shortener”) or upload an architecture image, and the tool asks our AI service (Groq by default, with other providers as fallback) for a STRUCTURED architecture — JSON only, never code — which is validated before rendering. The AI runs through our own secure server: the API key is stored server-side and is never in your browser, the client bundle, or any request you send. Starter conceptual templates work with no AI at all.
Yes. Drag nodes, connect and delete edges, rename components, change categories and technologies, add nodes, auto-layout, undo/redo and snapshot versions. You can also ask the AI to modify the design (“add Redis caching between the API and the database”) — the AI returns graph operations that are validated before they touch the diagram.
Any component can be expanded into its own sub-flow. “Explore subsystem” generates a more detailed graph for that component (e.g. a recommendation pipeline), and a breadcrumb lets you drill down and back without losing the parent architecture.
PNG, SVG and a shareable JSON design file (which round-trips back into the editor), plus a Markdown architecture document covering components, data flow and assumptions. Exports are made in your browser, and no API key is ever stored in them. Two things do leave your device: generating or editing a design with AI sends your prompt, and any architecture image you upload, to an AI provider; and Save and Share, which need you to sign in, store the design in your account — a shared design can be opened by anyone with its link. Signed out, designs are not saved anywhere: version snapshots last until you reload, so export the JSON file to keep your work.
Yes — it is a general prompt → architecture → interactive graph → explanation → drill-down → edit → export engine. Netflix, Uber, YouTube, a URL shortener, a chat app or a payment system are just examples that make it easy to understand.