Describe
Start with the contract your application already expects: operations, payloads, errors, and events.
Controlled environment for AI development
Run the whole loop.Break nothing real.
Mock every dependency around your backend so coding agents can integrate, retry, fail, and recover without touching production or spending against real providers.
DotDotMock guide Ready to model
What should your agent test?
Describe a dependency, a state change, or the failure you need to reproduce.
Dotis workingRead the dependency contract
Built deterministic state
Added timeout and retry
Verified the full trace
I built a stateful checkout mock with a deterministic timeout on the first attempt and success on retry. Nothing touched production.
OpenAPI contract Traffic trace Safe to rerun
A guided product demo · nothing is sent to a real provider
Mock third-party dependencies in development
Your app needs the dependency.Your dev loop doesn't.
Payment gateways, identity providers, CRMs, AI APIs, and partner services bring credentials, rate limits, costs, slow sandboxes, and unpredictable data into development. DotMock gives your application stable stand-ins shaped like the third-party APIs it already calls.
Replace a dependency in four moves
Keep your code. Swap the destination.
Your application still makes the same calls. In development, those calls go to a workspace you can shape, inspect, and reset.
Development routing controlled
01Your appunchanged client code
02DotMockprovider-shaped behavior
development.env
PROVIDER_BASE_URL=DOTMOCK_WORKSPACE_URLChange one environment value. Keep the integration path your application already uses.
Model
Add the behavior development needs—state, latency, retries, failures, streams, and webhook sequences.
Point
Swap the third-party base URL in your development or test configuration. Keep the application code.
Exercise
Run the real flow, inspect every exchange, and reset the dependency whenever you need a clean state.
Test the paths provider sandboxes skip
A 200 response is the beginning, not the mock.
Reproduce declined payments, expired tokens, rate limits, partial records, delayed webhooks, dropped streams, and recovery sequences on demand. Every developer and test run gets the behavior it needs without waiting for the provider to produce it.
Scenario library5 models
Card declined
402Expired token
401Rate limited
429Provider timeout
504Webhook delayed
eventExample failure modelPOST /v1/payments
402ResponseState changeInspect
{
"error": {
"code": "card_declined",
"message": "The card was declined.",
"retryable": false
}
} request matched payment.failed webhook queued
Mock the dependency you actually use
Keep the contract. Control the behavior.
Third-party systems are more than REST endpoints. Preserve the interface your client expects while taking control of its data, timing, state, and failures.
Explore the docsLLM APIs
OpenAI, Anthropic, Gemini, Bedrock, Azure OpenAI, Ollama, and Cohere routes with streaming, tool calls, usage, and failures.
REST
Payments, identity, shipping, CRM, and any OpenAPI-shaped service.
GraphQL
Queries, mutations, subscriptions, variables, and resolver errors.
SOAP
WSDL/XSD contracts, XML envelopes, enterprise operations, and faults.
gRPC
Protobuf services, metadata, status codes, and streaming behavior.
Realtime
WebSocket and SSE streams with scripted messages, timing, and recorded sessions.
Webhooks
Signed events, delayed delivery, retries, failure responses, and inspection.
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