One tool for designing software systems.
Sketch fast. Keep it rigorous. SketchBench is for engineers and architects who think best on a whiteboard and still need the design to hold up three months later.
The state of things
Design already happens. It just does not survive.
The cost of designing a system is not the drawing. It is the switching — every tool holds one representation, and your thinking does not.
Whiteboards forget
Fast and expressive right up until the session ends. Then the meaning goes with it, and what is left is a photo nobody opens.
Diagram-as-code taxes thinking
Durable, precise, versionable — and slow enough at the moment of authoring that you quietly stop exploring.
Docs drift
The prose and the diagram diverge within weeks. A design that has drifted is worse than none, because it lies with authority.
Chat leaves nothing behind
An agent gives you an answer in seconds and no structure at all. You rebuild the same context in every new session.
What SketchBench does
One model behind every way of designing.
One model, many surfaces
Whiteboard, diagram, outline, prose, or chat. Each one reads and writes the same underlying model, and every view is generated from it — so a diagram and a design doc cannot drift apart.
Structure when you want it
Start with untyped shapes and no schema. Promote them into typed components in place when you are ready, or never. Untyped content stays legal forever.
AI on your terms
A dial from zero to co-design. At zero, every workflow still completes — the product is whole, not degraded. At three, it proposes structure and argues alternatives.
Progressive formalization
Structure is earned, never demanded.
A tool that wants a schema before you can think is a tool you reach for after the design is finished, which is to say never. So SketchBench lets you put an untyped shape down and decide later what it was.
Promotion happens in place. The element keeps its position and its identity, gains a type, and starts appearing in the generated views — the context diagram, the design doc, the decision log.
Same element, same position, same identity. Promotion adds a type — it never moves your thinking to another screen. Demotion works too.
Surfaces
Work the way you are already thinking.
- WhiteboardInk, shapes, sticky notes, loose arrows. No schema.v1
- DiagramTyped nodes, validated connections, auto-layout.v1
- OutlineStructured editing of any node. Detail and bulk edits.v1
- Prose briefWrite a paragraph. Get a structure you can edit.v1
- ChatConverse with an agent that edits the model directly.v1
- Text / DSLThe model as compact text. Precise, diffable.later
- ImportIngest a repo, an OpenAPI spec, an existing diagram.later
Outputs
Everything leaves in an open format.
- DiagramsSVG and PNGv1
- MermaidRenders in any Markdownv1
- Design docNarrative Markdownv1
- Decision logOne file per ADRv1
- Agent context packFor Claude Code, Cursor, and the restv1
- Model JSONThe whole thing, portablev1
- IaC scaffoldTerraform, Pulumi, CDK — topology onlylater
The AI dial
You set how much of this is AI.
Per project, changeable at any time. Anything the AI writes is marked as its work until you accept it, and it never deletes what you wrote.
- 0
Off
No inference, no suggestions, no calls. A complete product.
- 1
Ambient
Naming, edge types, tidying, catching obvious inconsistencies.
- 2
Assistive
Generate structure from prose. Critique on request. Find the gaps.
- 3
Co-design
Propose whole structures, argue alternatives, iterate with you.
Being straight with you
What SketchBench is not.
- Not built yet. This is a waitlist, not a download. Nothing here is available to use today.
- Not a general-purpose whiteboard. Whiteboarding is scoped to system design — it is the untyped way into a model, not a canvas for retros.
- Not an application code generator. It produces designs, docs, and context. IaC scaffolds describe topology, not behavior, and they are a starting point you review and own.
- Not an enterprise architecture platform. No approvals, no governance, no review boards.
Know when it is ready.
One email when it ships. Nothing else, and no sharing your address with anyone.