Provides a unified TryLock/Unlock interface backed by either a local mutex or Redis-based distributed lock. Demonstrates clean abstraction for locking across multi-instance deployments. Self-contained with minimal imports (context, time, redis), easily extractable for any project needing distributed coordination.

A lightweight typed event bus that supports on/off/emit, once listeners, and a cache feature for replaying events to late subscribers. Pure TypeScript with no internal dependencies, making it immediately reusable in any web project. The cache pattern is non-obvious and useful for avoiding missed events during async initialization.

Centralized JWT token creation and validation for multiple token types (user auth, upload delegation, sandbox download). Uses HMAC-SHA256 with configurable expiration and claims. Well-structured with separate functions for each token purpose, making it easy to adapt for other projects needing scoped JWT tokens. Imports only standard library and the jwt-go package.

Implements a pipeline pattern for processing artifacts (files) with registered handlers. Each step is a separate handler registered in a central registry, allowing composition of sequential processing (e.g., preview, normalization, OOXML verification). This pattern is reusable for any file processing workflow and demonstrates clean separation through the Registry and Pipeline interfaces.

Factory for creating RAG pipeline steps based on a profile configuration. Each step implements an interface and is registered by name, allowing dynamic pipeline construction. This pattern decouples step creation from orchestration and is reusable for any system needing configurable, pluggable processing steps. The dependency injection via function options is clean and testable.