Path and URL Failures

Paths cross source, destination, and deployment layers.

That makes them excellent at producing confusing symptoms.

Source path failure

An include references a file that does not exist.

Jekyll may fail during rendering.

Generated path failure

A page's permalink changes but navigation still points to the old path.

The build may succeed.

The browser gets a 404 later.

Base-path failure

A root-relative /assets/... URL works in one hosting layout and fails under a repository baseurl.

Case failure

A path's letter case may appear harmless on one development filesystem and fail on a case-sensitive production host.

Diagnostic trace

For a broken link/image:

1 source file exists?
2 Jekyll generated/copied destination?
3 generated href/src value?
4 production base path?
5 requested browser URL?
6 target exists at that URL?

Lab

Create one link that works locally under your current setup but would be wrong under a non-empty baseurl.

Then repair it with the appropriate Jekyll URL strategy and verify generated output.

Checkpoint

State whether the bug was a source-file, generated-output, or deployment-addressing problem. Use evidence.