Design Task Management System
Last Updated: January 22, 2026
What is a Task Management System?
A task management system is a software tool that helps individuals and teams plan, organize, assign, and track tasks in an efficient and structured manner. It plays a key role in improving productivity, accountability, and collaboration especially in fast-paced, team-driven environments.
Loading simulation...
Popular tools like Trello, Asana, and ClickUp are examples of task management platforms designed to streamline workflows and improve team efficiency.
In this chapter, we will explore the low-level design of a task management system in detail.
Lets start by clarifying the requirements:
1. Clarifying Requirements
Before starting the design, it's important to ask thoughtful questions to uncover hidden assumptions, clarify ambiguities, and define the system's scope more precisely.
Here is an example of how a discussion between the candidate and the interviewer might unfold:
Candidate: Should tasks support hierarchical structures, like subtasks within parent tasks?
Interviewer: Yes, tasks should be able to have subtasks. A parent task can only be marked complete when all its subtasks are done.
Candidate: What states can a task be in? Just open and closed, or something more detailed?
Interviewer: Tasks should have four states: TODO, IN_PROGRESS, DONE, and BLOCKED. There should be rules about which transitions are valid.
Candidate: Should we track task history? For example, when status changed or who it was assigned to previously?
Interviewer: Yes, we need an activity log that records key events like creation, status changes, and assignment changes.
Candidate: How should users find tasks? Do we need full-text search or just filtering?
Interviewer: Simple filtering is fine. Users should be able to filter by status, priority, and assignee.
Candidate: Should tasks have due dates and priorities?
Interviewer: Yes, tasks should have optional due dates and a priority level: LOW, MEDIUM, HIGH, or CRITICAL.
Candidate: Can tasks be organized into lists or projects?
Interviewer: Yes, tasks belong to task lists. Users can have multiple task lists.
Candidate: How should I handle input? Console interface or hardcoded demo?
Interviewer: To keep things focused on design, you can hardcode a demo sequence showing the key features.
After gathering the details, we can summarize the key system requirements.
1.1 Functional Requirements
- Users can create, update, and delete tasks
- Tasks have a title, description, due date, priority, and status
- Tasks can have subtasks; parent tasks complete only when all subtasks are done
- Tasks can be assigned to users
- Tasks support tags for categorization
- Tasks can have comments
- The system should track activity history (creation, status changes, assignment changes)
- Users can filter tasks by status, priority, and assignee
- Tasks belong to task lists
1.2 Non-Functional Requirements
- The design should follow object-oriented principles with clear separation of concerns
- The system should be modular and extensible to support future features
- The code should be thread-safe for concurrent access
- The components should be testable in isolation
Now that we understand what we're building, let's identify the building blocks of our system.