This has been posted several times and there are tons of comments:

[1]: https://news.ycombinator.com/item?id=18146438 [2]: https://news.ycombinator.com/item?id=18138328 [3]: https://news.ycombinator.com/item?id=18145645 [4]: https://news.ycombinator.com/item?id=18138990 [5]: https://news.ycombinator.com/item?id=18141328