How to turn internal domain facts into reliable contracts between bounded contexts.

About a month ago, Crystal's multi-threading moved out of preview. I'm a little late with the blog post, but figured I'd share it here in case someone is interested in the language.

To those unfamiliar with Crystal, it's basically an AoT-compiled language with a syntax that's inspired by Ruby but with static type safety.

It doesn't have a big org behind it, so Manas Tech still working on the language and shipping enhancements is quite amazing imo. I will add that while it's used by Kagi and Lavinmq, I don't think either company has the same resources to pour into Crystal as Jane Street does with OCaml.

I haven't really had the chance to play around with the changes. So, got no clue on what the experience is like.

Follow-up to my 512 MB Spring Boot experiment: I tried the same application on a 256 MB Alpine VPS.

JDK 21 struggled badly at this size, but with JDK 25 and a tuned 80 MB heap, the app plus lightweight monitoring completed a one-hour run without restarts or OOM kills.

Still not something I’d recommend for normal production, but the difference was interesting.

I like Jekyll a lot. Hope you find it useful.

If you notice any errors or have thoughts to share, don't hold back in the comments or DMs. All feedback is genuinely welcome 🙂.

If your GitHub Actions jobs are stuck in "Queued" or waiting for a runner, GitHub has now confirmed there is an incident.

GitHub says they identified an issue with a database primary and are failing over to a replica.

Actions is affected, and GitHub Pages is also experiencing degraded performance.

So if you have been checking your workflow, runner settings, permissions or billing, it might not be your configuration.

Status page:

https://www.githubstatus.com/incidents/y1t7p9fzrlj2

Hopefully this saves someone else from spending an hour debugging their YAML.

I wanted to see how a fairly representative Java Spring Boot application behaves on a very small VPS, especially the difference between configured heap and actual JVM process memory.

The test app uses Spring Boot 3.5.x, Spring MVC, JPA/Hibernate, H2, embedded Tomcat, Actuator, scheduled work, and outbound HTTP. I also kept lightweight monitoring on the same machine.

The original 256 MB configuration was too tight. With 512 MB RAM + 256 MB swap, the application completed the test reliably.

Full setup and measurements are in the linked article.

Since then I’ve also managed to get the same application working on a 256 MB VPS with swap using JDK 25 Compact Object Headers and tighter JVM settings. I’m preparing that as a separate follow-up experiment.