As a former V8 engineer, I was actually relieved that they were not running V8. V8 would be overkill for their needs.
> JS runtimes are so widely used that they’re extremely well debugged and very fast.
This would be true if these systems weren't constantly changing, both because the language keeps evolving and the runtime techniques keep evolving.
The truth is that JS runtimes are extraordinarily complicated pieces of software, and they have bugs, sometimes very subtle ones. Sometimes bugs have been hiding for years, and sometimes they are new. This despite being developed by some of the best engineers I have ever worked with, being daily pounded on by billions of people, and fuzzers with thousands of cores.
> This would be true if these systems weren't constantly changing, both because the language keeps evolving and the runtime techniques keep evolving.
Seconded as a former SpiderMonkey engineer. As a safety guy, trusting an optimizing JIT is the stuff of my (professional) nightmares and the fact that the language keeps evolving, has semantics that very few people on Earth actually understand fully and that (very smart) developers keep cramming new optimizations within them.
Oh, and add to that the fact that they're pretty much all written in C++, which is already the stuff of nightmares for safety professionals, and that they rely on garbage-collectors that need to walk both JavaScript and C++ heaps.
I would trust a small, certified, non-optimizing implementation of a JS runtime much more than any of the juggernauts out there.
I'm not the v8 engineer, but I do maintain software that embeds v8. quickjs is a breath of fresh air compared to using v8. it's missing some features that v8 has (isolates, etc), but has an extremely fast startup, an api that doesn't change constantly, and is much much much smaller/easier to build.
> JS runtimes are so widely used that they’re extremely well debugged and very fast.
This would be true if these systems weren't constantly changing, both because the language keeps evolving and the runtime techniques keep evolving.
The truth is that JS runtimes are extraordinarily complicated pieces of software, and they have bugs, sometimes very subtle ones. Sometimes bugs have been hiding for years, and sometimes they are new. This despite being developed by some of the best engineers I have ever worked with, being daily pounded on by billions of people, and fuzzers with thousands of cores.