Programmers write source code that compiles to programs, and users execute the programs to benefit from their features. While issue-tracking systems help communication between these two groups of people, feature requests have usually been written in text with optional figures that follows community guidelines and needs human interpretation to understand what to implement in which part of the source code. To make this process more direct, intuitive, and efficient, a streamlined interaction design called “User- Generated Variables (UGV)” is proposed. First, the users can declare parameters that they want to tweak in existing programs without reading or understanding the source code. Then, the system turns the proposal into variable declarations in the relevant part of the source code. Finally, the programmers are notified of the proposal and can implement the actual features to reflect changes in the variable value. The proposed interaction is implemented in two existing Web-based Integrated Development Environments, and its user experience is briefly tested with eight users and programmers. Its technical requirements, limitations, and potentials are discussed. The content of this paper with live demo will be available at http://junkato.jp/ugv.