Costin Stefan

My website is now part of 512kb.club - a curated list of sites whose total size is under 512KB. That’s it. Half a megabyte. Even less, actually, because my blog was reported at 410K. In 2026, when even basic websites are rebuilt as React applications, that almost feels rebellious. Modern websites routinely ship multiple megabytes of JavaScript, tracking scripts, animations, fonts, and frameworks just to render a few paragraphs of text. We’ve normalized shipping entire applications to display a landing page. ...

So recently I had to play with BGP after a very long time. I have a router that connects to external via an eBGP session. It gets default route from there and it advertises the originating prefixes. All worked great until I wanted to advertise a new /24 subnet. The problem was that I have this subnet split into many /27s on different SVIs, and even though I’ve included it in the prefix-list to be advertised over the BGP session, this would not come up. ...

In this one I will show you how I improved the performance of a WordPress site using CloudFlare Caching and PHP FPM pool settings. But a bit of context. I have 2 WP websites running on the same VPS behind nginx, with 2 different conf file. Pretty standard deployment so far. On this VPS I have root access, so I’m able to play a bit more with other stuff, not just standard cPanel settings. ...

As part of my freelancing business, I recently had to fix a space issue on a Windows machine. And the issue was caused by a very large text file. I know the Linux way of emptying a file, which is to redirect STDIN to the file. But on Windows I had to find a way to do it. Of course I tried the easy way and I thought that AI would be able to provide a quick answer. ...

So I had a really interesting issue recently where one of our app devs was complaining that he can’t get the container ID from within the container in a new environment. For context, there’s a setup with 3 identical environments on the customer side and a local lab that was recently replaced. I’ve deployed a new Openshift cluster (version 4.14. will become important later) to replace another lab environment in a different location. ...