# grpc

Cloud-native distributed vector search engine built for Kubernetes with automatic indexing and horizontal scaling.

Vald is a highly scalable distributed approximate nearest neighbor (ANN) vector search engine designed for cloud-native, Kubernetes-based architectures. Maintained by LY Corporation and listed in the CNCF Landscape, it uses the NGT algorithm (developed at Yahoo Japan), supports automatic incremental index backup, and handles billion-scale datasets across loosely coupled microservice components that scale horizontally via Helm.

Open-source multi-protocol API client

Firecamp is an open-source API DevTool supporting REST, GraphQL, WebSocket, and Socket.IO protocols as a lightweight alternative to Postman. It provides IntelliSense, team collaboration with shared workspaces, and seamless import from OpenAPI, Insomnia, AsyncAPI, and HAR formats. Each protocol gets a dedicated testing playground with response metrics including time, size, and status codes.

Versatile microservice framework for any protocol

Armeria is an open-source microservice framework from the creator of Netty at LINE Corporation that supports gRPC, Thrift, REST, and GraphQL on a single server and port. It provides built-in decorators for metrics, distributed tracing, load balancing, authentication, rate limiting, circuit breakers, and automatic retries. The framework integrates seamlessly with Spring Boot, Dropwizard, and Reactive Streams while serving automated API documentation with interactive request testing.

Open-source MCP server for database access

MCP Toolbox for Databases is an open-source MCP server by Google that connects AI agents to databases through a managed control plane. It handles connection pooling, authentication, and tool distribution, letting developers integrate database tools in under 10 lines of code. Supports PostgreSQL, MySQL, BigQuery, AlloyDB, Snowflake, MongoDB, Redis, ClickHouse, Neo4j, and more with ready-to-use toolsets for Claude Code, Gemini CLI, and other MCP clients.

Open-source API client

Open-source API client by Kong for designing, debugging, and testing REST, GraphQL, gRPC, and WebSocket APIs. Features a clean interface with environment variables, authentication helpers, code generation, cookie management, and response timeline. Supports OpenAPI and Swagger specs for design-first workflows. Git Sync for version-controlled API collections. Available on macOS, Windows, and Linux. A popular alternative to Postman with stronger focus on privacy and local-first usage.

API development and testing platform

The most popular API platform used by 30M+ developers worldwide. Build, test, and document APIs with collections, environments, automated testing, and team collaboration. Features mock servers, monitoring, API design tools, and a vast public API network. The industry standard for API development workflows from prototyping through production testing and documentation.