Wix Mid Fullstack developer- Wix Boost interview questions

System design interview with two parts. 1. Talk about project you did 2. system design question about implementing shopping cart functionallity in early stage wix Had 2 interviweres 1 of them was a junior with 2 years of experience as the shadow interviewer who called me wrong mistakenly and told me I dont know the technology. They thought my project was "over complicated" even though it is a valid, practical and very good