diff --git a/_posts/2024-09-27-diff-check-is-on-github-marketplace.md b/_posts/2024-09-27-diff-check-is-on-github-marketplace.md
new file mode 100644
index 0000000..5d91c98
--- /dev/null
+++ b/_posts/2024-09-27-diff-check-is-on-github-marketplace.md
@@ -0,0 +1,29 @@
+---
+title: "diff-check is on GitHub Marketplace"
+tags: project github-actions
+---
+
+Today, I cut the [first release (v1.0.0)][3] and [published diff-check to
+GitHub Marketplace][2].
+
+[`diff-check`][4] came out of seeing a common pattern of seeing side effects
+when another automated process would run, creating more work which wouldn't be
+seen at the time. It was really common when I was working on React Native
+projects (if you upgrade an `npm` dependency, you'll often get a change in the
+`Podfile.lock` that Dependabot wouldn't know about), but less frequently in
+projects using Appraisal (another project I maintain). I [previously wrote up
+how it works in the announcement blog post][1].
+
+With some help from [Oscar Gustafsson][5] (thank you!), he helped see some bits
+I'd got wrong and also pointed out some small ways in which we could improve
+the output too. Several weeks ago, [I'd also merged in a PR to use this on
+Administrate][6] and so now I'm pretty happy it's working.
+
+I'd love to hear if it works out for you!
+
+[1]: https://nickcharlton.net/posts/diff-check-github-action
+[2]: https://github.com/marketplace/actions/diff-check
+[3]: https://github.com/nickcharlton/diff-check/releases
+[4]: https://github.com/nickcharlton/diff-check
+[5]: https://github.com/oscargus
+[6]: https://github.com/thoughtbot/administrate/pull/2609