Show HN: NetDiag.Dev – Website Connectivity Diagnostics API (opens in new tab)

Originally I thought it would be cool to expose something like dstp over HTTP: a simple way to run low-level network diagnostics remotely via a REST API. Then I ditched dstp and rewrite every check with .NET. Then I added the obvious next step - run the same check from different geographic regions, because most real incidents aren’t local. I already had a few servers for side projects, so it was easy to try.

At some point I switched to full grug-dev mode and cut everything that wasn’t essential. No agents, no setup, no monitoring, no accounts. One request in, parallel checks from multiple places, raw results back. The goal is that you can curl it during an incident and immediately answer "is this broken everywhere, or just from here?"

There's also an OSS sidecar for people who want to self-host monitoring, but it still needs some tuning.

I'm not fully sure about the next step yet, probably a small paid tier to cover server costs and buy a coffee, but for now the public API has fairly generous limits even without an API key if you want to play with it