The Figma alternative where designs already run.

This is the structural difference everything else follows from. A Figma file is a description of software: vectors, frames, and fills arranged to look like a product. It is a very good description, but someone still has to build the thing it describes. A Prototyper canvas holds the software itself. The screens compile, the buttons respond, the forms validate, and the code behind them is the code a team would ship.

That difference decides what feedback means. Critique on a mockup is a guess about how the real thing will feel; critique on a running screen is a fact about it. Motion, latency, focus states, and awkward empty states show up in the first review instead of the first release.

Figma has been adding AI features inside its own surface, and tools like Make generate app code in a separate view. The model in both cases belongs to the platform: you use the AI you are given, metered the way the platform meters it.

Prototyper inverts that. You bring your own agent, Claude Code, Codex, Cursor, or Copilot, and it joins the canvas over MCP as a worker with a real file system. It reads your sketches and stickies, builds next to you, and answers to your direction. The subscription you already pay for does the heavy lifting, and switching agents is your call, not ours.

Direction happens the way design direction always has: you point at what is wrong and say why. The agent revises on the canvas, in front of the team, until your eye says yes. No prompt engineering course required.

The true cost of a mockup-first workflow is the rebuild. A designed feature waits for an engineering sprint, gets re-implemented from redlines, and returns for review weeks later with drift the designer has to catch and file. Teams have normalized a four-to-six-week gap between "designed" and "real", plus the meetings that police it.

Prototyper does not compress the handoff. It deletes the step. The screen the designer approved is already built, so engineering effort moves to the parts that genuinely need it: data, infrastructure, and the hard logic behind the interface. Designers get their review time back too, because there is no drifted build to police.

In Figma, a prototype is frames connected by transition links. It demos a scripted path well, and for early flow reviews that can be enough. But a click-through only works while the user stays on the path you wired. There is no real input, no state, no data, so a test participant is reacting to a film of the product rather than the product.

A Prototyper prototype is an application. Users type into the form and hit its validation, sort the table, land on the empty state you forgot to design, and wander off the happy path the way real users do. The findings from a test session describe the software you will ship, because it is the software you will ship.

Figma remains the stronger tool for org-scale static design operations: thousand-component libraries, brand systems, illustration, and the governance workflows large design orgs run on. Its ecosystem of plugins and community files has a decade of compounding behind it, and nothing here pretends otherwise.

Prototyper earns its seat where the goal is a product someone can use: product screens, flows, prototypes that face users, and the path from a validated prototype to shipped software. If your week is mostly the second list, that is the seat we are arguing for.

Most teams do not switch in a day, and we would not advise it. The pattern that works: keep Figma for brand, illustration, and the marketing surface, and move product screens and flows to Prototyper, where they become running software from the first draft. Your design tokens and components come with you, so output matches the product you already have.

There is no Figma file import, and that is deliberate: you would be importing a picture. Start from a sketch, a screenshot, or a sentence, and the agent builds the running version directly. Teams usually port their two or three most active flows first and let the rest follow as they come up.

Trying it costs an afternoon, not a procurement cycle. The canvas is free to start, reviewers never need a paid seat, and the AI construction runs on the agent plan your team already pays for. Put one real flow through the loop and judge the review cycle against your current sprint.