How to eat an elephant in pieces: task decomposition in the development of complex IT products

We tell you why a team needs task decomposition and how you can divide product development tasks.

What is decomposition

Figuratively speaking, decomposition is the ability to “eat an elephant in pieces”, that is, to divide a large task into several small ones and perform them one by one, achieving the intended result. But in IT things work a bit more complicated, because in software development tasks are rarely so homogeneous.

Key features of decomposition in IT:

1. Unequal tasks – the parts into which a project is divided often differ significantly in complexity and scope of work.
2. Preserving integrity – when dividing, it is important not to forget the overall meaning and properties of the “elephant” (the entire project).
3. Automation – developers often seek to automate repetitive tasks rather than perform them manually.
4. Flexibility – the requirements for the final product can change and it is important to take this into account when decomposing.

“When dividing a large product into smaller tasks, the team must not lose the overall vision. It’s like with the metaphorical elephant: if you get too close, you can only see the trunk and mistake it for a snake. It’s important to keep perspective and remember that you are working on a whole product, not a set of disparate parts”,

– Ksenia Filippova, Product Owner SimpleOne SDLC

Decomposition plays an important role in IT product development, helping teams deal with complex tasks more effectively:

1. Accurate time estimation: By breaking down a large task into smaller parts, a team can more accurately estimate how much time each step will take. This helps to plan project timelines more realistically
2. Adherence to the “one task, one sprint” rule: in Agile-development, there is a rule: a task must be achievable within one sprint, usually no more than 4 weeks. Decomposition helps break down large tasks so that they fit within that time frame.
3. Risk Assessment: small tasks are easier to analyze for potential problems. This allows you to identify risks in advance and prepare for them.
4. Prioritization: decomposition often makes it clear which requirements are really important and which can be done without. This helps to narrow down the scope of work and focus on the essentials. When the project is broken down into parts, it is easier to understand which tasks are most important and where it is best to start.
5. Better understanding of tasks: the team will have a deeper understanding of tasks if they are small and detailed – this will have a positive impact on the quality of development.

Decomposition makes a complex development process more manageable and transparent. It allows the team to see both the big picture of the project and specific steps to its realization. It is a key tool for successful management of IT projects of any scale, ensuring efficiency, flexibility and quality of development.

What can be decomposed

During the IT product development process, various elements of a project are decomposed. The hierarchy of elements depends on what is accepted in the team, usually these are:

1. Epics are large blocks of work that typically cover a significant portion of the product’s functionality.
2. Features are more specific product features or capabilities that are included in epics.
3. User Stories and Tasks – these elements are on the same level. User stories describe specific product usage scenarios, while tasks describe the technical steps to realize them.
4. Subtasks – the smallest units of work into which tasks can be broken down for more detailed planning.

Roles at different levels of the hierarchy:

• Product Owner (Product Owner) works at the epics and features level: he/she collects requirements, conducts market analysis and forms the main directions of product development.
• Analyst works with the Product Owner to create user stories for each feature, detailing requirements.
• The development team works with stories, tasks, and subtasks. For example, when conducting a code review, subtasks can be created to fix identified issues.

Principles of decomposition

While there are no strict rules for decomposition, there are a number of principles that help break down tasks effectively:

• Logical isolation

Each decomposed task should represent a logically complete piece of work.

• Moderate scope

Tasks should not be too small or too large. The optimal size is what the team can accomplish in a single sprint (usually no more than 4 weeks).

• Value to the user

Each task should carry some value to the end user.

• Testability

The result of the task must be measurable and verifiable.

• Independence

Tasks should be as independent of each other as possible so that the team can work on different parts of the project in parallel.

• Flexibility of implementation

The task should not contain a specific way of implementation – the team should have space to discuss and choose the best solution.

• Comprehensibility for the team

Decomposed tasks should be clear and understandable for all team members.

INVEST criteria are often used to evaluate the quality of User Stories decomposition:

These criteria help ensure that the decomposed tasks are optimal for the work and meet the project goals.

It is also important to keep balance in mind when decomposing:

• Don’t break down tasks too finely so that the overall vision of the project is not lost.
• Don’t leave tasks too large that are difficult to estimate and accomplish in a single sprint.

Methods of decomposition

There are several basic ways of task decomposition in the IT product development process. The choice of a particular method depends on the specifics of the project, the preferences of the team and the features of the product being developed.

It is important to note that these methods are not mutually exclusive and can often be combined within a single project. Flexibility in the approach to decomposition allows you to effectively structure the work and ensure that all participants in the development process understand the tasks.

Functionality

This method involves breaking down the task based on the functionality of the product. For example, when developing a task management system, you can distinguish such parts:

• project creation and management;
• user and role system;
• creation and editing of tasks;
• comments and discussion system;
• notification system;
• reporting and analytics.

Each of these parts is a separate functionality that can be developed and tested independently, but together they form a complete task management system.

By user role

Decomposition is done by considering the different roles of the users of the system. For example, when developing a code management and continuous integration (CI/CD) system, the following roles and corresponding functionality can be identified:

1. Developer:
   • cloning repositories;
   • creating and managing branches;
   • commit and push changes;
2. Reviewer code:
   • viewing changes in pull-requests;
   • add comments to code;
   • approving or rejecting changes;
   • starting additional checks;
3. DevOps Engineering:
   • configuring CI/CD Pipelines;
   • manage deployment environments;
   • configuring automated tests;
   • monitoring build performance;

This decomposition allows to clearly define the functional requirements for each role in the technical context of software development and lifecycle management.

By interface

This method involves breaking down the task based on the elements of the user interface. For example, when developing a control panel for a server monitoring system, the following components can be identified:

1. Top navigation bar:
   • server selection menu;
   • buttons for quick access to the main functions;
   • general system status indicator
2. Side panel with detailed information:
   • list of active servers;
   • filters for sorting servers;
   • quick search by name or IP address.
3. Main data display area:
   • CPU, RAM and disk load graphs;
   • table of current processes;
   • real-time log files;

This decomposition allows developers to focus on individual interface elements, ensuring consistent and logical implementation of all dashboard components.

Based on CRUD operations

Decomposition based on basic data operations: Create, Read, Update, Delete. For example, this is how you can decompose user management functionality in an e-commerce system:

1. Create:
   • development of a new user registration form;
   • validation of input data (email, password, personal information).
2. Read:
   • display of personal information (name, email, delivery address);
   • display user’s order history
3. Update:
   • creation of a form for editing a profile;
   • the ability to change the password with confirmation by email;
   • update delivery address;
4. Delete:
   • delete related data (orders, reviews, favorite products);
   • sending confirmation of account deletion to email.

This way of decomposition allows you to structure the work on the functionality, ensuring that all user data actions are fully covered.

Use Scenarios

This method involves separating the main use case and alternative branches. For example, when creating a task management system, the main scenario might be “Create and manage a task”:

1. user creates a new task;
2. fills in a description, assigns an executor and sets a deadline;
3. task appears in the list of active tasks;
4. the executor updates the status of the task as it progresses;
5. when completed, the task is marked as completed.

Alternative script branches may include:

• changing the task priority;
• adding a comment to the task;
• reschedule the due date;
• create a subtask;

By product module

Decomposition can be performed on the basis of logical modules of the system – first the product is divided (decomposed into modules), and then each module is divided into separate tasks. For example, to develop a CRM-system, the following modules may be allocated:

1. contact management module;
2. sales module;
3. marketing module;
4. customer service module;
5. analytics and reporting module;
6. integration module;
7. administration module;
8. mobile access module.

Each module makes up a logically isolated part of the product – this method is similar to process decomposition.

List of tasks divided by product modules in the SimpleOne SDLC

Task decomposition in a development management system

Effective task decomposition and management requires a user-friendly development management system. SimpleOne SDLC provides tools for working with task hierarchy and supports the decomposition process:

• flexible structure of task types: epics, fics, user stories, tasks, subtasks;
• ability to create links between tasks of different levels;
• convenient interface for visualizing the hierarchy of tasks;
• support for different views: lists, kanban boards;
• tools for estimating and scheduling tasks;
• the ability to flexibly customize workflows to meet the needs of the team.

Task Hierarchy in SimpleOne SDLC

SimpleOne SDLC enables the effective application of decomposition principles, providing transparency into the development process and helping teams better manage complex projects.

Resume

Task decomposition is a tool that allows you to effectively manage complex IT product projects. By breaking large tasks into smaller pieces, teams can more accurately estimate work time, reduce risk, and improve the quality of the final product. The key to successful decomposition is striking a balance between detail and maintaining the overall vision of the project.

A team can choose any decomposition method: from breaking down by functionality to breaking down by user scenarios. The choice of approach depends only on the specifics of the project and the team.

To simplify the decomposition process, it is worth controlling tasks with a development management system, such as SimpleOne SDLC – this will help provide transparency in the links between tasks, user stories and epics.