Timeline

Published the first follow-up entry in the new threaded timeline model.

Timeline entries can now point back to earlier entries, which turns the feed into more of a build log than a flat list. This update continues from the original timeline launch and marks the point where parent and follow-up relationships became part of the feature.

The implementation for this lives in PR #17.

Added a personal timeline feed to the site. Markdown files in timeline/, same front matter as posts. Color is tag-driven: shipped goes green, published goes blue, thinking goes amber — no extra fields needed.