Well there was a post few year back with title "Best-architected open-source business applications worth studying?" : https://news.ycombinator.com/item?id=14836

Well there was a post few year back with title "Best-architected open-source business applications worth studying?" : https://news.ycombinator.com/item?id=14836013 https://news.ycombinator.com/item?id=14836013