The IndieWeb has a nice concept of building blocks that lets you build focused interoperable bits of algorithms that can work together for a cohesive experience.
- Trying to determine who posted the content you’re looking at? Try authorship.
- Curious about that cross-platform posting support? POSSE - Post On (Your) Site, Share Elsewhere is the concept.
- How can you send a ‘ping’ / notification to someone’s Web page? Use Webmentions
There’s a lot more on the Wiki.