Build a web app to streamline employee shift scheduling and management

We're looking for a developer to build a shift management system (a browser-based web app) for a company with 10–50 employees. [Overview] We currently manage shift scheduling manually (using Excel, chat tools, etc.) and would like to move this to a web app to improve efficiency. [Key Features] - Employees can submit their shift preferences - Admins can create, adjust, and review shifts - Confirmed shifts can be viewed and shared in a list format - User account management with role separation (admin / general staff) Note: Detailed requirements are not yet finalized — we'd like to work through them together after the contract starts. At this stage, only the general direction is set. [What We Have in Mind] - Accessible via browser on both PC and smartphone - Able to handle growth in user numbers without performance issues [What We'd Like You to Propose] - Your recommended tech stack (framework, database, etc.) - A rough development timeline and approach - Relevant past work or portfolio examples [Budget & Process] - Estimated budget is around 100,000–300,000 JPY (roughly $650–$2,000 USD), though this can be discussed based on your proposal - We'd like to start with a requirements discussion to align expectations before moving into full development Note: Day-to-day communication will primarily be conducted in Japanese, but we're open to working with freelancers who can communicate clearly in English as well. Feel free to reach out with any questions or proposals.