What about this project made it L6? Is it because it was a high priority for execs? Is it because you had to get a lot of buy-in from external team(s) in the Chrome org?
It's the combination of it being an exec priority + the industry consensus at the time being "It's impossible". If you deliver a high-priority project that any engineer can glance at and have an immediate idea how to solve, that's L4 work. (Say, you're shuffling data from protobuf to a bunch of Javascript on screen.) If you deliver a high-priority project that most engineers are declining to work on or saying "It can't be done", that's L6 work. If you deliver a high-priority project and then publish it externally and then the rest of the industry actually says "Woah, this is revolutionary and really valuable to us" and then Doug Cutting clones it over at Yahoo and releases it as open-source and spawns a whole sub-industry, that's L9 work.
This is all for IC engineering. I actually prefer to think of the ladder in organizational terms which also encompass management, but the sub-thread here is specifically interested in what it takes to be an L6+ IC.
