Ask HN: Companies Encouraging Work/Life Balance

On the back of the discussion around the "Less Stress, More Productivity" article (https://news.ycombinator.com/item?id=12320188), I'm curious which companies actively work to keep their employees on < 40 hours a week?

Please include company name, website, and any other details you'd like to include (why you try to work shorter hours, what's your experience with hiring/retention, are you hiring currently, etc).