The Nunjucks race condition in Eleventy 3.x affects page.url too —
its value changes between {% set %} and {{ }} within the same
template render during parallel builds. Instead of trying to derive
slugs from page data, name OG images with the full filename
(including date prefix) to match URL path segments exactly.
Eleventy v3 parses YYYY-MM-DD- from filenames and removes it from
page.fileSlug. The OG generator was using the full filename (with
date prefix) causing a slug mismatch — hasOgImage filter checked
for 'slug.png' while the file was 'YYYY-MM-DD-slug.png'.
Also removes debug logging from hasOgImage filter.
The OG generation in the eleventy.before hook consumed too much memory
alongside Eleventy's data cascade, causing the Eleventy process to be
OOM-killed on Cloudron. Fix by running OG generation in a separate
child process with its own 768MB heap limit. Also write the manifest
incrementally (every 10 images) to preserve progress if interrupted.
Uses Satori + @resvg/resvg-js to create branded 1200x630 social
preview cards at build time. Cards show post title, type badge,
date, and site name on a dark background with blue accent.
Generated images are cached in .cache/og/ (persistent on Cloudron)
and passthrough-copied to the output. Posts with photos continue
using their own images. Untitled posts (notes) use body text.
