Ask HN: Is There a “Glassdoor” for Engineering?

I'm wondering if there's a service that gives me an unbiased / anonymous perspective of what it's like to be an engineer at a company.

There's Glassdoor, but that's mostly about culture and a general sense of the vibe and career trajectory at the company.

Technical blog posts published by companies are definitely interesting and provide a glimpse of what interesting things one might work on, but they also have the hidden agenda of wanting to attract talent, so of course they're only going to shine a positive light on the company.

I want to know specifically how an engineer feels about company "x". And how engaging the work is, and what technical management is like at company "x".

Does this exist?