Activitypub-federation is a high-level Rust framework for implementing ActivityPub federation. It provides abstractions for handling incoming and outgoing activities, fetching remote objects, managing HTTP signatures, and integrating with web frameworks like Actix-web and Axum. The library uses a trait-based design where users define their own data structures and implement Object, Activity, and Actor traits to plug into the federation system. It includes sophisticated features like an activity queue with exponential backoff retry logic (1 minute, 1 hour, 2.5 days), automatic caching of remote objects, and comprehensive security measures including HTTP signature verification.
Upvote RSS is a monolithic PHP web application that generates RSS feeds from social aggregation platforms including Reddit, Hacker News, Lemmy, Lobsters, PieFed, Mbin, and GitHub. The system features a modular architecture with separate classes for authentication, community-specific APIs, post processing, content parsing, and AI summarization. Users configure feeds through a web interface built with vanilla JavaScript web components, and the application employs sophisticated caching (Redis, APCu, filesystem) to optimize performance. The platform supports optional features like AI-generated summaries, content extraction, comment inclusion, and NSFW filtering.