Tantivy is an embeddable Rust search engine that can index and process any kind of content, including structured data (if fed to it properly). If I define a comprehensive search schema, the following features can be implemented:

• Searching by tag
• Searching by title or content (full-text search)
• Sorting of all posts by date

I wonder if I should make unlisted posts indexable -- probably not? I wonder if "unlisted" should be just "absent from all feeds" or "only available using a link". This needs research.