Ask HN: Which companies have the best blogs written by their engineering team?

Depends what you want to get out of them. I find some are mostly focused around some of the more unique/cool challenges they come across (Google[1][2], Slack[3]), and others are more about how they solve the engineering challenges they face through software and/or about their dev process (Uber[4], Twitter[5]). Some are mix of the two (Dropbox[6], Netflix[7]).

[1] https://developers.googleblog.com/

[2] http://research.googleblog.com/

[3] https://slack.engineering

[4] https://eng.uber.com/

[5] https://blog.twitter.com/engineering

[6] https://tech.dropbox.com

[7] http://techblog.netflix.com/

Some more good ones that have not been listed yet.

https://code.facebook.com/posts/

https://medium.com/@Pinterest_Engineering

https://redditblog.com/topic/technology/

StitchFix do lots of interesting ML stuff, such as Chris Moody's lda2vec. Their algorithms page is really cool: http://algorithms-tour.stitchfix.com/#recommendation-systems

Curious why you don't like Cloudflare.

General Electric are at the forefront of industrial engineering and quite good at blowing their own trumpet.