Rendering tags into URLs makes them unstable

Right now, for some reason I don't understand, all tags are rendered into post URLs serially. For instance, a post with tags "pinned" and "release" will end up with blog/pinned/release/<name>.

First, this suggests a hierarchy that does not make any sense. Tags don't have an order. Second, the URLs become unstable unless you maintain the tags as they are forever. As just showcased, we make mistakes with tags. For instance, our last post contained "release", although it's more of a "meta" post. Fixing this issue changes the URL unfortunately.

Unstable URLs are a problem in many cases. The following list contains a few examples:

• links in the browser history render a 404
• links indexed by search engines might not work any more
• links contained in third-party websites will become invalid

I think we should change the way our URLs are generated. The URL should directly reflect the filename or, alternatively, the post name, perhaps adding a year and maybe even month to avoid collisions.

We also need to consider implementing some forwarding logic for the existing posts. We should not render them a second time, but instead we could probably just generate HTML pages that meta-forward to the new location. This can be done for all new posts as well, as it is unlikely to cause issues in the future.

The issue names no files, tests, or entry points. Start by locating the blog post URL generation and existing-post rendering logic, then compare current tag-based URLs with filename- or title-based alternatives. Done means a stable URL scheme is chosen and existing URLs receive forwarding pages without duplicate post rendering.