Hakyll caches per-page outputs, so pages whose dependencies have not
changed are not recompiled and the rendered $build-time$ in their
footer goes stale relative to a fresh build. The right granularity for
"last built at" is site-wide rather than per-page; wrapping the footer
timestamp in <span data-build-time> and rewriting it after Hakyll lets
every page reflect the current build without paying recompilation cost.
* tools/stamp-build-time.py walks _site/**/*.html after Hakyll runs and
rewrites each element wrapped in [data-build-time] to the same format
Contexts.hs:buildTimeField emits, so a fresh render and the post-pass
agree.
* templates/partials/footer.html wraps $build-time$ in
<span class="footer-build-time" data-build-time>...</span> so the
sweep has a stable selector.
* Makefile invokes the sweep between embed.py and compress-assets so
the .gz/.br sidecars include the fresh stamp.
Co-Authored-By: Claude Opus 4.7 <noreply@anthropic.com>
