We developed Hi-sap, a web server system that ensures the security in a server and has high performance when processing dynamic content. In existing servers, server embedded programs cannot be used safely in large-scale environments like a shared hosting service. These problems occur because server processes run under the privilege of a identical user. For example, server embedded interpreters are commonly used to improve performance in processing dynamic content, like weblogs and wikis. However, other customers that share the same server can steal, delete, and tamper with data files of weblogs and wikis. To solve these problems, we designed a new web server system, Hi-sap. In the system, web objects that are stored in a server are divided into partitions. Server processes run under the privilege of different users in every partition. We implemented Hi-sap on a Linux OS and tested the effectiveness of the system. Experimental results show that Hi-sap has high performance and scalability.