I consider Hacker News (news.ycombinator.com) to be a high-quality digital public sphere. Run by the prestigious seed-stage incubator Y Combinator, Hacker News surfaces user-submitted links and posts using an upvote and downvote system and allows users to comment on submitted content. Here is a screenshot of part of the front page:

In general, the content focuses on matters relating to the software engineering community, including news of startup funding and acquisitions, hot technical topics such as machine learning, and occasionally relevant political issues like net neutrality.

In terms of impact, I think Hacker News has done incredibly well. In general, with at least 200,000 unique visitors each day, including successful and well-connected individuals from across the tech community, it provides high visibility to important causes in the community. Many web startups report that they need to beef up their server infrastructure to prepare for launches on Hacker News, which can drive tens of thousands of people to their websites if they reach the Hacker News front page. A front-page appearance can put a startup on the radar of important venture capitalists and set the stage for a round of funding. Hacker News’ impact isn’t limited to putting startups in the limelight. It has also been used to publicize campaigns to raise money for prominent software developers struggling with illnesses and raise awareness of (supposed) injustices like the prosecution of hacktivist Aaron Swartz. A search for “Thank you HN” on the site yields posts by individuals thanking the community for helping them find jobs, and even one post from a father who said that Hacker News’ popularization of an article about his son’s undiagnosed medical issues led him to parents of other children with similar problems and eventually to a diagnosis.

In terms of productive discussion, Hacker News has been successful as well. The comment sections of front-page links are always filled with lively and informed discussion. When users launch their side projects or startups with “Show Hacker News” posts, other users provide useful feedback in the comments. If a project has already been done before, you can be sure that at least a few people who see the post will know and point that out. In general, people with a wide variety of experience across the technical stack frequent Hacker News, so new products will get critiqued from a number of angles, including front-end design, technical sophistication, product-market fit, and more. On expository articles about technical topics, users from industry, academia, and other communities will post their own experiences with those topics, adding further color to the articles and providing additional data to either support or refute their claims and generalizations.

This is not to say that Hacker News cannot be improved or has gone without criticism. Some have claimed that community members are too harsh in criticizing posted projects that are not very polished or clearly lacking in some areas. The authors of such projects, who are likely new to software development, may be so discouraged by the negative feedback that they become reluctant to work on software again. The maintainers of Hacker News have acknowledged this issue and implemented changes to the algorithm that surfaces comments to mitigate the problem. Another issue is that community members are generally of a similar political and ideological bent, so posts that espouse conservative values are unlikely to reach the front page. So, while the upvote and downvote system brings many benefits – likely the filtering of disrespectful or technically inaccurate content – it can also shelter users from opposing views.

In all, despite some minor shortcomings, Hacker News is a strong community and certainly the premier forum for topics related to software engineering and technology.