Our worldview

Deterministic systems must exist before prompt and context optimization can mean anything.

DotMock is a hosted mock server for REST, GraphQL, SOAP, gRPC, realtime, webhook, and LLM provider APIs. Coding agents and developers point an application at it instead of a real dependency, then run success, failure, and retry paths without touching production.

Why DotMock exists

Agent-driven development makes software loops faster and more autonomous. It also makes every unstable dependency, irreversible side effect, and missing trace more expensive.

We believe agents need a controlled environment in which they can integrate, fail, retry, recover, and produce evidence. That environment should speak the real protocol, preserve state, emit the real kind of outbound event, and make every material change inspectable.

DotMock is that environment around the backend. It is not a replacement for the backend, a prettier fake response, or a claim that prompts can compensate for nondeterministic systems.

Principles

Contracts before improvisation

Model the interface and its behavior before asking a model to guess what the world looks like.

Safe loops over impressive demos

A complete, reproducible failure-and-recovery path matters more than a polished happy-path response.

Evidence over confidence

Traffic, state changes, deliveries, drafts, and approvals should be visible and attributable.

Native behavior over lowest-common-denominator mocks

REST, GraphQL, SOAP, gRPC, LLM APIs, and webhooks deserve their own contracts and runtime semantics.

DotMock at a glance

What it is: DotMock is a hosted mock server for the APIs a backend depends on. It is operated by Olio LLC. Details
Interfaces: 7 interface types: REST (OpenAPI), GraphQL, SOAP 1.1 and 1.2 (WSDL/XSD), gRPC (protobuf, unary and streaming), realtime SSE and WebSocket, LLM provider APIs, and webhooks. Details
LLM providers: 7 LLM provider API shapes from one mock: OpenAI (Chat Completions, Responses, embeddings), Anthropic Messages, Google Gemini, AWS Bedrock, Azure OpenAI, Ollama, and Cohere. Details
Streaming and failures: LLM responses stream over SSE with a default chunk size of 20 characters, configurable time to first token and tokens per second, and injectable drops, malformed frames, disconnects, and 429 rate limits. Details
Testing in CI: CI jobs test against the hosted mock with a DotMock API key secret: fixtures apply from the repository, and each run gets its own X-Dotmock-Session for isolated sequences and journal assertions (preview in @dotmock/cli 0.3.1). Details
Automation: Agents manage mocks through the DotMock CLI or the MCP server at https://mcp.dotmock.com/mcp, authenticated with a team-scoped API key. Details
Pricing: Free ($0 a month) includes $1 of monthly usage for one workspace; paid plans draw every live interaction from one prepaid USD balance, and live runs pause at zero instead of billing overage. Details

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