Ask IH : Best places for growth marketing knowledge

Ok, each one of us needs to 'get out of the building' once we have that spanking new MVP ready. This may be for feedback or to validate our assumptions or for folks to try out what we've created or for potential customers to pay for our offering.

I'm wondering what are some of the forums, blogs, subreddits, slack channels, medium publications or websites that you find yourself returning to frequently when you think about letting the world know about what you've created?

Not looking for one awesome post or growth hack but something consistent over a period of time like IH, YC news that one may visit consistently to develop a broader perspective.

I'd add one that I visit regularly : https://www.groovehq.com/blog/startup-journey