Navigation

No navigation is ever hardcoded in Tartarus. Four components read the same content tree at build time.

Sidebar

The sidebar renders the top-level section of the page you are on. Sub-sections become collapsible groups; a group is expanded when it contains the current page, or when it is shallower than sidebarCollapseDepth.

[params]
  sidebarCollapseDepth = 2   # levels 1 and 2 start open

If a section's _index.md has body content, an Overview link to it appears as the first item in its group.

Alpine holds one boolean per group — whether it is open. The list itself is static HTML rendered by Hugo, so the navigation is complete and crawlable without JavaScript.

Breadcrumb

Derived from the page's ancestors, home excluded:

Documentation / Core Concepts / Navigation

Disable it globally with showBreadcrumb = false.

Table of contents

Built from Hugo's heading fragments, limited to ## and ### by default:

[markup.tableOfContents]
  startLevel = 2
  endLevel = 3

A small IntersectionObserver marks the heading you are reading. Clicking an entry is a plain anchor jump — smooth when the browser allows it, instant when the reader prefers reduced motion.

Previous and next

Both links come from the flattened reading order of the current section. Hidden per site with showPrevNext = false.