TypeScript interface
→ JSON sample

Paste your interface

// JSON sample will appear here

The problem it solves

You have TypeScript interfaces. You need JSON — for tests, for mocking an API response, for Storybook args, for documenting an endpoint. The options are all slow:

• •Write fixtures by hand, then keep them in sync as types change
• •Ask a colleague what a real response looks like
• •Dig through network logs hoping to find a real example
• •Wire up faker.js and spend 20 minutes mapping every field

TypeMorph reads the field names in your interface and generates a plausible value for each one. An email field gets an email address. A created_at field gets an ISO timestamp. The output is ready to paste into a test or a mock handler.

In CI — keep fixtures in sync with your types

# Generate a JSON sample from a TypeScript file
typemorph reverse src/types/user.ts

# Pipe to a fixture file
typemorph reverse src/types/user.ts > fixtures/user.json

# Read from stdin
cat src/types/user.ts | typemorph reverse

The CLI command reads your TypeScript source and writes JSON to stdout. Pipe it into a fixture file and your test data automatically reflects the latest shape of your types.

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