From Jekyll to Astro (via Posterous, via Gatsby)

· 5 min read

This blog has now had four homes. It started on Posterous around 2005 as a linklog, back when the Delicious-era pattern was “here’s a URL and a sentence about it”. Posterous shut down in 2013, so the content moved to Jekyll, then to Gatsby in 2019, and this week it’s landed on Astro.

Every one of those migrations was triggered by the same thing: the previous stack quietly rotting while I wasn’t looking. This time the nudge was GitHub reporting 120 vulnerabilities on the default branch.

The Gatsby dep-tree situation

The site itself was fine. A pile of static HTML served by GitHub Pages, no server, no user input, no runtime dependency risk at all. But the build tree was Gatsby 2 from 2019, which by 2026 was dragging in dozens of packages with published CVEs: sharp, node-forge, trim, glob-parent, nth-check, and a few hundred more transitively.

None of it was reachable by a visitor. All of it fired every time CI ran npm install. And Dependabot, to its credit, would not shut up.

The tempting fix is npm audit fix --force, but Gatsby 2 has no compatible upgrade path, so you end up with a broken build and the same CVEs. The real fix was ripping the build system out entirely.

Why Astro

I looked at Hugo, Eleventy, Next static export, and Astro. Astro won on four things.

Content collections with a Zod schema for frontmatter is the feature I didn’t know I wanted. Every post has to satisfy the schema at build time, so a typo in a date or a missing title fails the build instead of silently shipping a broken page. Zero JavaScript goes to the browser by default, and the site is now less than half the size of the Gatsby version of the same content. Islands are there if I ever want interactivity, without paying for a framework I don’t use. And the dep tree is small and modern enough that npm audit comes back clean.

The whole migration took an afternoon, most of it spent on content rather than code.

The archive was the interesting part

I had 704 old posts sitting in src/content/blogs/, in three flavours: Jekyll .markdown files from 2011 to 2012 with fairly reasonable frontmatter, Posterous exports as .html with inconsistent frontmatter and raw HTML bodies (many pointing at dead posterous.com/getfile/… images, since Posterous went dark in 2013), and a handful of “real” .md posts from the Gatsby era.

So, a three-script pipeline, all kept in scripts/:

  • normalise-archive.mjs pulls dates out of filenames when the frontmatter is missing them, coerces everything to .md, and drops the WordPress/Posterous-era junk fields.
  • detect-linkposts.mjs does strict detection of the Posterous linklog bookmarklet shape (a leading anchor where the display text is the URL itself), and promotes the target URL to a link: frontmatter field. 475 posts matched.
  • htmlify-to-markdown.mjs runs turndown over the HTML bodies to get CommonMark out, strips the dead posterous.com images, unwraps the Posterous-specific div wrappers, and swaps those echoed leading anchors for markdown equivalents.

After the pipeline: 703 files are pure markdown, and one is a nested HTML table I chose not to fight with. It’s a Sean Connery personality quiz, because of course it is.

Linkblogs deserve a convention

The bit I actually like about this setup is the linkblog affordance. Any post with a link: field gets its title rendered as an outbound link on both the list and the post page, a small ∞ internal permalink so you can still link at my post rather than only at the destination, a visible (host) chip on the archive listing, and a → glyph so the eye can pick out a link post at a glance.

Daring Fireball has been doing this since forever. The pattern is well established and yet almost nothing supports it natively, which is a shame, because it’s a couple of lines of schema and a bit of template logic.

Design

The visual design is Catppuccin Mocha, a warm dark palette I’ve enjoyed elsewhere, plus JetBrains Mono throughout and a prompt-style header (qnm:~/path $ ▍) with a blinking block cursor. There’s a Latte toggle for when the sun’s out.

Nothing here is trying to look like a magazine. It’s meant to look like a terminal, because that’s where I spend most of my day.

Numbers

  • 704 posts built, going back to 2005
  • 0 npm audit vulnerabilities
  • 6.1 MB dist/, down from 13 MB on Gatsby
  • ~1 second clean build
  • 120 → 0 vulnerabilities reported by Dependabot

Deploying

The CI pipeline is embarrassingly simple:

- uses: actions/checkout@v7
- uses: withastro/action@v6
- uses: actions/deploy-pages@v5

That’s the entire deploy. GitHub Pages picks up the artifact and serves it. No branch to push, no third-party actions, no personal access tokens.

Should you migrate?

Probably, yeah. If your blog runs on anything that had its peak in the Gatsby era, the dep tree is bad news by now, and moving is cheaper than you think. Astro’s markdown pipeline is close enough to Jekyll’s that the port is mostly mechanical, a couple of hours if your archive is less chaotic than mine.

The pipeline scripts are pretty portable. If you’ve got a Posterous or Jekyll archive gathering dust somewhere, feel free to steal them.