That doesn't help with non-deterministic failures and I've also yet to see a true "write once, run anywhere" system ever. It may be 99% "write once, run anywhere" but there's always that 1% edge case.

Exactly. This just reminds me of "works on my computer". Building locally is more advantageous for developing CI workflow, but I want to be as close to prod as possible and doing that on snowflake developer workstations is an exercise in futility.

[delayed]

All flakiness I’ve observed in code I’ve written has been dominated by things like “this job isn’t getting enough cpu cycles and the test assertion is too aggressive in such a scenario” or “lack of CPU cycles is triggering a race condition” or “statistical test X isn’t written robustly”. Not sure how containers solve these problems. My point being that this tool solves some problems for some teams and maybe for a lot of teams that struggle with this problem, but hard problems remain and this isn’t a silver bullet for that. You can’t outsource stability of the project-specific test infrastructure which is where most of the cost lies these days I think.

Nix solves all these problems for good. It's a monster of a system, but if you're migrating anyways then might as well migrate to the real deal, not to some fly-by-night half-baked thing that gets you halfway there.