org_web/posts/career/requirements-features.org

Requirements, features, user stories, tasks, walking skeletons

• Requirements
• Epic
• Features
• User Stories
• Tasks
• Walking Skeleton
• Hierarchy Overview
• Example from work:

Requirements

• Definition: High-level descriptions of what the system must do or how it should behave.

• Types:

  • Functional: Specific behaviors (e.g., “The system must allow users to reset passwords”).
  • Non-functional: Quality attributes (e.g., performance, security, usability).
• Agile Context: Requirements are often evolving and are captured incrementally through user stories and feedback loops.

Epic

An epic is a high-level objective or initiative that’s too big to complete in a single sprint. It represents a major business goal or capability and is broken down into smaller deliverables:

• Purpose: Organise related work under a common theme.
• Scope: Broad and strategic; spans multiple sprints.
• Example: “Enable secure user access” could be an epic that includes login, signup, password reset, and multi-factor authentication. “An epic serves to manage tasks. It's a defined body of work that is segmented into specific tasks (called ‘stories’) based on the needs/requests of customers or end-users"

Features

• Definition: Distinct pieces of functionality that deliver value to users.
• Scope: Larger than user stories but smaller than epics.
• Example: “User profile management” could be a feature encompassing login, profile editing, and avatar upload.

User Stories

• Definition: Short, simple descriptions of a feature told from the perspective of the user.
• Format: “As a [user], I want [goal] so that [reason].”
• Purpose: Helps teams focus on user needs and prioritize work.
• Agile Role: Central to backlog grooming, sprint planning, and iterative delivery.

Tasks

• Definition: Technical or operational steps needed to implement a user story.
• Granularity: Smallest unit of work, often assigned to individual team members.

• Example: For a story like “User can upload avatar,” tasks might include:

  • Create upload UI
  • Validate image format
  • Store image in database

Walking Skeleton

• Definition: A minimal, end-to-end version of the system that includes the core architecture and basic functionality.
• Purpose: Validates the system’s structure early and allows incremental development.
• Agile Benefit: Enables early integration, testing, and feedback while avoiding big-bang delivery.

Hierarchy Overview

Level	Description	Agile Artifact
Vision	Broad business goals	Epics
Feature	Functional chunks of value	Features
User Need	Specific user goals	User Stories
Implementation	Technical execution steps	Tasks
Skeleton	Minimal working system	Walking Skeleton

Here is a summary of the agile hierarchy:

Level	Example	Description
Epic	Enable secure user access	Broad goal spanning multiple features
Feature	User Login	Functional unit delivering user value
User Story	“Log in with email/password”	Specific user goal within the feature
Task	Build login form, connect to backend	Technical steps to implement the story

Example from work:

<2025-10-09 Thu> The user story creation we did for a particular made up project (not the proudest but team voted on this sadly).