TypeScript Interface Architect

Write a TypeScript interface for a complex nested API response — handling optional fields, union types, and ISO dates correctly.

Skills Tested

TypeScript typingInterface designUtility types

Challenge Prompt

This is the example prompt structure. Write your own variation below.

Write TypeScript interfaces for this API response:
{
  "user": {"id": "uuid", "email": "string", "role": "admin|editor|viewer"},
  "subscription": {"plan": "free|pro|enterprise", "expires_at": "ISO8601|null", "seats": number},
  "permissions": [{"resource": "string", "actions": ["read","write","delete"]}],
  "metadata": {"created_at": "ISO8601", "updated_at": "ISO8601", "tags": string[]}
}
Requirements: (1) use strict TypeScript, no 'any', (2) dates as string with JSDoc comment noting ISO8601, (3) union types for enums, (4) export all interfaces, (5) add one utility type that extracts only the subscription fields.

Your Prompt

Write your own version. Every word matters — be specific.

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Reward

+200 GeraCoins

Earn GeraCoins for completing this challenge. Redeem across all Gera products.

Hints (3)

1"No any" is the most important constraint — it forces proper typing of all fields.
2Utility type requirement (Pick<Subscription, ...>) tests advanced TypeScript knowledge.
3JSDoc comments on date fields help future maintainers without changing the type.