Plenty of engineers on the market can work professionally in C. Only a small amount of people can write Cobol (or is willing to given that is almost useless). That alone is a good reason to consider Cobol a legacy language and throw away a codebase written in Cobol.
Using DynamoDB in 2025 is such a weird proposition. Horrible dev experience, no decent clients/libs, complex pricing, weird scaling in/out mechanism, slow, it only works well for well defined use-cases.
Possibly because they capture the video from xvfb or similar (they run a headless browser to capture the video) so at that point the decoding already happened (webrtc?)
Nice article which matches my experience when it comes to optimizing for performance: Linux defaults are never good defaults and you don't need webscale or anything before you get bitten by them.
To make a few examples: on many distributions you get 1024 as the file limits, 4KB of shared memory (shmall) and Nagle's algorithm is enabled by default.
Another thing that we noticed at work (shameless plug to getstream.io) when it comes to tail latency for APIs / HTTP services:
- TLS over HTTP is annoyingly slow (too many roundtrips)
- Having edge nodes / POPs close to end-users greatly improves tail latency (and reduces latency related errors). This works incredibly well for simple relays (the "weak" link has lower latency)
Running workers ourselves was the last resort, we tried everything else but it was impossible to get fast (and consistent) build times otherwise.
In a way we are now going to get charged for Github's poor execution on Actions.