Model your domain.
Generate your data.
Visually build domain models from your DDD design, then generate realistic, relationally coherent mock datasets instantly.
Free forever · No credit card required
Why Mocktopus?
No more hand-written fixtures
Stop maintaining test data by hand. Your domain model is the single source of truth — mock data updates automatically when your model changes.
Mocks that match your real schema
Mocktopus reads your exact entity relationships, field types, and constraints. Generated data always fits your actual data shape.
Catch bugs real data reveals
Realistic values and proper relational integrity surface edge cases that hand-crafted fixtures miss. Test with confidence.
How it works
Model your domain
Add entities with fields and types. Define relations between them. The visual editor makes your domain model tangible.
Visual domain editor
Publish a version
When your model is ready, publish it. The classifier checks for consistency issues and creates an immutable versioned snapshot.
Versioned snapshot
Generate mock data
Pick a version, set record counts per entity, and generate. Referential integrity and constraint rules are enforced automatically.
Mock output
Everything you need
Visual domain editor
Model entities, value objects, and domain events in a clean visual editor. Relations are drawn as connections.
Relational coherence
Generated datasets respect every relation. Every Order references a real User. Every reference resolves.
Type-safe constraints
Twenty constraint kinds across value, relational, temporal, and cross-field scopes. Generated data always satisfies every rule.
Cross-field rules
Express object-level rules: required-if, excluded-if, exactly-one-of, at-least-one-of, sum-equals. The solver enforces them on every generated record.
Reusable value objects
Define a value object once — Money, Address, Coordinates — and use it as a field type on any entity. Nest them to any depth.
Domain events
Author past-tense domain events with payload fields and entity impacts. The events screen documents how your system changes.
Draft, publish, version
Edit in a draft, publish to create an immutable version, then browse the full changelog. Mock generation runs against a chosen version.
JSON & CSV export
Export your mock datasets as JSON or CSV. Flat structure for CSVs, nested for JSON.
Developer API
Query your mock data via a REST API. Use it in CI, in seeds, anywhere.
Start modelling your domain today
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