A lightweight, self-contained utility that enables extensible function composition without inheritance. It wraps a function to allow registering patches that run before or after the original call, with priority ordering. This pattern is used extensively across the codebase to add enterprise features (e.g., air-gapped restrictions, contact merging) without modifying core code. The implementation is generic and could be extracted to enable similar extensibility in any TypeScript project.

A pure JavaScript implementation of AES-GCM encryption and decryption using the Web Crypto API. It handles key generation, encryption of data, and decryption with proper IV management. The module is well-tested (with spec files), isolated from business logic, and depends only on standard crypto primitives and small internal utilities (@rocket.chot/random, @rocket.chat/base64). It demonstrates high craftsmanship in cryptographic implementation and is reusable in any project requiring AES encryption with a similar API.

A centralized, typed implementation of the DDP (Distributed Data Protocol) serialization and deserialization layer. It defines message types, parsing, and stringification for all DDP messages (connect, method, sub, unsub, etc.). This module is decoupled from the rest of the client and serves as a single source of truth for DDP wire format. It could be extracted to implement a DDP client or proxy in any JavaScript/TypeScript project without depending on the full Meteor ecosystem.