Networking
You Fixed CORS and the Browser Kept Failing for Ten Minutes
Access-Control-Max-Age caches the preflight decision, including the one that said no. Here is why your fix looked like it did not work.
Rohit Bhadani
I write about why software breaks and how people figure it out. Founder of Krova Cloud, building isolated microVMs on our own hypervisor. Years of Shopify theme work and shared hosting before that. If I have not reproduced it, I do not publish it.
MicroVMs
The CORS Header Is Present Twice and That Is Why It Fails
You added the header at the proxy, your framework was already sending it, and the browser now rejects both. Duplicates are invalid, not additive.
MicroVMs
Debugging Production Without Touching Production
The bug only reproduces with real state. Copying the database loses the parts that matter. Cloning the whole machine keeps them.
DevOps
Consumer Lag Is Not a Throughput Problem Until You Prove It Is
Lag climbing on one partition while the rest keep up tells you something specific. Here is how to read the numbers before you add consumers that cannot help.
MicroVMs
I Let an Agent Run rm -rf and Nothing Bad Happened
The question is not whether an autonomous agent will do something destructive. It is what the destruction can reach when it does.
JavaScript
The Dashboard That Got Slower the Longer You Left It Open
A single page app that was fine for an hour and unusable by the afternoon. Three wrong hypotheses, then a heap snapshot showed forty thousand detached DOM…
MicroVMs
413 Request Entity Too Large When You Already Raised the Limit
You raised the body size limit and the upload still fails. There are almost always two limits, and the one you changed is rarely the one rejecting you.
MicroVMs
The Service Is Running, Listening, and Completely Unreachable
curl works on the box and hangs from outside. Four places the packet can die, and how to tell which one killed it without guessing.
Networking
TLS Handshake Failures: the Error the Server Actually Sent
handshake failure, protocol version, unknown ca and bad certificate all mean different things. Here is how to get the real reason out of a connection that…
MicroVMs
The Domain Resolved Everywhere Except Where I Was Sitting
A CNAME that dig confirmed, a browser that refused, and a certificate stuck on pending. Three separate caches pretending to be one problem.
MicroVMs
Your Database Got Slower and Nothing in Your Code Changed
Query times doubling at unpredictable hours with no deploy and no traffic spike. When the cause is not in your process, it is usually not on your machine…
DevOps
Your systemd Service Will Not Start and the Logs Say Nothing
status=203/EXEC, status=217/USER, and the other exit codes that mean something specific. Here is how to read them and what each one actually points at.