Inventory of goods is one of several important factors in a company, whether engaged in trading or manufacturing. It is important for inventory to be controlled and supervised in the recording and calculation of inventory, this is because inventory can affect financial reporting. If the amount of inventory is too large (overstock), on the other hand, if the inventory is a little, it will have an impact on the lack of inventory (stockout). The purpose of this research is to develop an inventory control system using the moving average method and the development of an Extreme Programming (XP) system. The moving average method in inventory prediction is more effective because this method compares current and previous data. To develop the system, the Extreme Programming (XP) system development method is used. This method has advantages including: fast process, time and cost efficiency, low risk, flexibility and easy to implement. From the test results using black box testing by testing the functionality, the system shows the system has met expectations with a value reaching 100%. Meanwhile, for testing with the DeLone and McLean models which measure the success of information systems, the score reaches 81.37%.

Public complaints are essential for the government to see how successful it is in carrying out activities. Public complaints are an essential element for local agencies because complaints are aimed at correcting the shortcomings of the activities that have been carried out. The absence of an electronic complaint system will hamper the complaint reporting process, so repairing deficiencies in government agencies will be hampered. The delay in repairing deficiencies in the agency will, of course, also affect the services provided to the community. The government can certainly use technology development to improve public services from the government to the community. This study discusses the development of an online-based public complaint system with the website-based Extreme Programming (XP) method that the public can access so that complaint reports can be submitted in real-time. The results of testing the complaint system from the usability side show an average value of 88.7% in the excellent category, so the application is feasible to use and as needed.

The school financial information system if managed very well will be an advantage in the implementation of activities and become a good spearhead for an educational institution. The current problem of processing school financial administration data is ineffectiveness and efficiency in the processing of school financial data, so it greatly affects the speed in determining a decision by high-level school management. The purpose of this research is the application of the user experience design model in making the modeling of the school financial information system very effective which folds system users in every system design starting from the stages of understand, research, sketch, design, implementation, and evaluate. The results of the school financial information system modeling test using a user experience design model for testing system functionality using blackbox testing got a value of 100% according to the functionality of the system, and the test results of Web Quality 4.0 got a value of 87.69% having excellent criteria from usability testing conducted on users.