Components

Click to add, or drag onto the canvas. Not every option belongs in a good design.

Custom block

Drag from a node's edge dot to connect. Select and press Del to remove. Ctrl Z undoes.

0 components · 0 connections

A blank canvas. A better system.

Add components from the palette, then drag between them to connect the request and event flow.

React Flow

Press enter or space to select a node. You can then use the arrow keys to move the node around. Press delete to remove it and escape to cancel.

Press enter or space to select an edge. You can then press delete to remove it or escape to cancel.

Need a starting point?

This exercise supports named primitive fields, required/optional markers and explicit defaults, with readers ignoring unknown fields. It does not claim to implement every real serialization format.

See progressive hints →

API contracts and data model

Describe operations, inputs, outputs, errors and ownership. Pseudocode is welcome. At least 80 characters for the completeness check.

0 characters

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