stuff

gistfile1.txt

Not all of them are blogs (some are weekly newsletters)

http://rubyweekly.com/
https://rubythursday.com/
http://rubyfacets.com/
http://blog.appsignal.com/
https://www.toptal.com/developers/blog/tags/ruby
http://www.nateberkopec.com/ (blogs about ruby and other stuff)
http://solnic.eu/ (author of ROM, dry-rb gems etc)
https://twin.github.io/
https://aaronlasseigne.com/posts/
https://blog.codeship.com/ (mixed content not only about ruby)

other than that I lookup https://www.reddit.com/r/ruby/new 2 times a week :)

For non ruby stuff I'm subscribed to https://this-week-in-rust.org/ and also lookup https://www.reddit.com/r/rust/new/ quite often