While listening to the Perfect Guide lecture, I was curious about the certification and testing, and the environment configuration that was more helpful for practical work. It was a lecture worth the name. I was preparing to change from Spring development to view development and was afraid of the spa development that I was encountering for the first time, but after finishing the curriculum, I am full of confidence and I feel regretful about the front-end development that I had been doing. I am very grateful for the class. Thank you.