Protocol Buffers

Cap'n Proto is a binary data interchange format, interface definition language, and capability-based RPC system developed around core tools and a C++ library. Its generated code lets programs in multiple languages read a shared memory layout without an additional serialization step, and it provides RPC capabilities for communicating between components. The project describes itself as a binary alternative to JSON and as a faster alternative to Protocol Buffers; the repository contains the development branch and warns that it may include breaking API changes.

FlatBuffers is a cross-platform serialization library and interface definition system developed by Google. It uses schemas written in `.fbs` files and the `flatc` compiler to generate language-specific code, which constructs and accesses serialized buffers directly without first parsing or unpacking them. The shared buffer layout supports reading data across languages and schema versions, and is designed for memory-efficient transmission, storage, and access. The project provides code-generation and runtime support for languages including C, C++, C#, Dart, Go, Java, JavaScript, Kotlin, Lua, PHP, Python, Rust, Swift, TypeScript, and others. It runs on Windows, macOS, Linux, Android, and other systems with a recent C++ compiler, and is licensed under the Apache License 2.0.

gRPC is an open-source Remote Procedure Call framework for connecting services across environments and data centers. It uses Protocol Buffers for service definitions and binary serialization, then generates client and server stubs for multiple languages and platforms. The framework supports HTTP/2-based transport, bidirectional streaming, pluggable load balancing, tracing, health checking, and authentication, and can also connect devices, mobile applications, and browsers to backend services. gRPC is a CNCF incubation project.

Sockudo is a self-hosted, high-performance Rust real-time server for WebSocket and HTTP publishing. It targets strict Pusher Protocol V1 compatibility for drop-in use, while Protocol V2 adds Sockudo-native events, serials, message IDs, recovery, rewind, tags, deltas, annotations, and mutable message events. The platform supports durable history, hot replay buffers, two-tier recovery, presence history, push notifications, webhooks, rate limiting, TLS, Prometheus metrics, Docker Compose, and Helm. Horizontal fanout can use Redis, Redis Cluster, NATS, RabbitMQ, Google Pub/Sub, Kafka, Pulsar, or Apache Iggy. The monorepo includes the Rust server and workspace crates, dashboards, deployment assets, documentation, official real-time and server SDKs, and an optional AI Transport SDK.

RabbitMQ is an open-source messaging and streaming broker for communication between distributed applications and microservices. It supports open protocols including AMQP 1.0 and MQTT 5.0, with client libraries for multiple programming languages. Applications can publish messages to queues or streams, route and filter them to consumers, acknowledge delivery, replicate messages across clusters, and connect deployments using shovels or federation. Common uses include decoupling services, remote procedure calls, event streaming, and IoT messaging; in the cited video, it transports events between booking services. The software is available under the Mozilla Public License 2.0, and Broadcom offers a commercial Tanzu RabbitMQ edition with enterprise support.