Overview

GripMock is a self-hosted gRPC mock server for developers who need predictable service behavior in local or automated tests. Its strongest fit is a team that wants to model realistic calls, including streams and failures, without a live backend; it is less suitable for teams seeking a managed service.

It combines configurable stubs with several ways to run them, from containers and standalone installs to an embedded Go SDK. The MIT license and free, open-source model remove subscription costs, but teams remain responsible for deployment and operation.

Key features

Request matching and response control

Stubs can match request data and headers using exact values, partial matches, regular expressions, glob patterns, and any-of rules, with priorities for resolving overlapping matches. This lets teams route different client inputs to distinct scenarios instead of relying on one generic reply. Dynamic templates can draw from payloads, headers, and stream position, while status errors and response delays help exercise client error handling and timeout behavior.

Streaming and runtime editing

Unary, server-streaming, client-streaming, and bidirectional calls are supported, making GripMock useful for clients whose behavior depends on more than a single request and response. The web dashboard can create, edit, and remove stubs while the server runs, and shows which stubs have been matched or remain unused. That visibility helps identify unexercised cases, though it does not replace the work of setting up and maintaining the mock server.

Service definitions and integrations

GripMock can load .proto files or compiled .pb descriptors, including descriptors pushed to a running server without restarting it. It can also start from a Buf Schema Registry module reference. Installation options include Docker, Homebrew, release binaries, a shell script, and Go; an official GitHub Actions guide supports CI workflows. For Go projects, the embedded SDK runs GripMock inside the test process without a separate container or binary, avoiding an extra deployment step for that use case.

Security and observability

Native gRPC TLS and optional mutual TLS client-certificate authentication support encrypted connections and client authentication. OTLP trace export and a Prometheus-scrapable /metrics endpoint provide hooks for teams that want to observe the mock service alongside their test infrastructure. GripMock also exposes Model Context Protocol endpoints for AI agents and tool-driven automation. These features broaden its integration options, but it remains a mock server rather than a general-purpose gRPC client.

Pricing

GripMock is free and open source under the MIT License, with no paid tiers or seat charges described. That makes it straightforward to use in local development and CI without a subscription decision; the tradeoff is that teams operate their own deployment. The project directs bug reports and questions to GitHub issues.

Platforms

GripMock is listed for API, Linux, macOS, Windows, web, and self-hosted use. Its deployment choices include containers and standalone installation, while the dashboard provides a browser-based management surface. gRPC-Web support and server reflection extend its usefulness across client and service workflows.

Who it's for

GripMock suits developers and QA teams that need controlled gRPC dependencies in local development, CI, or containerized test environments. It is particularly well matched to services with streaming calls, request-dependent responses, or failure and timeout cases to cover. Go teams can embed it directly in tests; teams outside that use case can choose among its documented installation paths.

It is a weaker fit for organizations that want a vendor-operated mock service or centralized service management: GripMock is self-hosted, and the documented support route is GitHub issues.

Pros and cons

Broad scenario coverage: Matching rules, dynamic templates, streaming patterns, status errors, and delays let teams model varied client interactions without a backend.
Flexible test integration: Docker, CI guidance, standalone installs, and an embedded Go SDK accommodate different test setups.
Live visibility and edits: The dashboard shows matched and unused stubs and supports changes without restarting the server.
Operational ownership: Self-hosting avoids subscription charges but leaves deployment and upkeep to the team.
Community support route: Questions and bug reports go through GitHub issues rather than a described paid support channel.

Alternatives

For a broader comparison, see gRPC Tools. Choose ghz instead when the priority is open-source gRPC load testing through a CLI or Go package, rather than configuring service-response mocks.

gRPC Swagger is another free option for API, self-hosted, and web environments. grpcmock-go is worth considering when Go-focused gRPC testing utilities are the goal.

Choose Kreya instead if you want a cross-platform gRPC tool for Linux, macOS, or Windows with a free individual plan; its request history is limited to the latest request, and it is not open source.

Bandura offers a free plan for personal and commercial use with no account, paid seats, or feature tiers; its commercial licence is a separate option. FintX offers a free/open-source plan with unlimited gRPC clients, request autosave, import/export, method tabs, a JSON editor, and projects, making it an alternative for those client workflows.

grpcmd is a free cross-platform option for sending requests, starting a server, using reflection, listing and describing methods, and JavaScript scripting. grpcui is another free choice for Linux, macOS, Windows, web, API, and self-hosted use.

Verdict

Choose GripMock if your team needs a free, self-hosted way to model gRPC behavior in development or CI, especially when streaming, request-sensitive replies, and failure cases matter. Its combination of live stub editing and multiple deployment paths is a practical advantage. Look elsewhere if you need a managed service or prefer a client-oriented tool rather than operating a mock server.

	Bandura	GripMock
Free plan	Yes	No
Free trial	No	No
Paid from	Free	—
Open source	No	No
Platforms	Linux, macOS, self-hosted, Windows	api, Linux, macOS, self-hosted, Web, Windows
Free plan	Yes	—
Deployment model	desktop	self_hosted
Server reflection	Yes	Yes
CI integration	Yes	Yes
gRPC-Web support	—	Yes
Mock server	—	Yes

Bandura vs GripMock

Bandura

GripMock