An open-source online judge system based on Python and Vue. Based on Docker; One-click deployment. Separated backend and frontend; Modular programming; Micro service. ACM/OI rule support; realtime/non-realtime rank support. Amazing charting and visualization. Template-problem support. More reasonable permission control. Multi-language support: C, C++, Java, Python2, Python3. Markdown & MathJax support. Contest participants IP limit(CIDR). You can control the menu and chart status in rankings.