I followed along and it didn't work because of a typo. I found out it was a typo when I contacted by email. I got a quick response and it was resolved well. The lecture content was also good because I could follow along to create a bulletin board. It was an e-government standard framework that companies actually use, and the development method was almost the same, so it was good. The only regret was that the last lecture only had materials and was not a follow-along lecture, but it was enough. And I asked for the company code, but I didn't know that you would answer that either. I think this price is cheap. I like it. The library source code is also attached, and I like it even more because you can copy and use it. I learned a lot at a cheap price.