From a technical perspective it hasn't been long enough for systemic failure to happen, financial failure might happen sooner. Think about how much day to day

From a technical perspective it hasn't been long enough for systemic failure to happen, financial failure might happen sooner. Think about how much day to day effort is spent on keeping systems you work on running. Not new feature development or bug fixes or running reports or weird user errors but actual effort to keep the system "up". Its not much from my perspective. It will take time, perhaps long periods of time, before the tech stack starts aging past EOL dates for supporting elements it runs on (OS, DBs, messaging stacks, web frameworks, etc.) If twitter runs on their own built hardware vs. cloud services that are maintained by others then they probably have even more runtime because another entity won't be rolling cluster and other upgrades to their infrastructure. The gloom and doom predictor people won't want to admit that twitter can train and staff up people over time so that site reliability won't be a factor. What should concern folks here is non-technical management at other places thinking they can do things like this as well. Don't think for a minute that what we do is specialized to the point that they can't let you go immediately.