✅ What is Requirement Engineering?
Requirement Engineering (RE) is the process of defining, documenting, and maintaining the requirements in the engineering design process of a software system.
It ensures the software meets the needs of its users and stakeholders before development begins, reducing costly changes later.
🔹 Why is Requirement Engineering Important?
Helps build the right product.
Reduces rework, cost, and project failure.
Improves communication among stakeholders.
Forms the foundation for design, development, and testing.
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<h2>Requirement Engineering Process</h2>
<p>Five stages that turn stakeholder needs into a managed, verifiable specification.</p>
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<div class="rf-flow" id="rfFlow">
<div class="rf-step is-open" data-index="0" tabindex="0" role="button" aria-label="Requirement Elicitation">
<div class="rf-index-row"><span class="rf-dot" style="background:#2ecc71"></span><span class="rf-num">01</span></div>
<h3 class="rf-title">Elicitation</h3>
<p class="rf-blurb">Collecting requirements from stakeholders.</p>
<div class="rf-detail">
<p class="rf-detail-row"><span class="rf-label">Techniques</span>Interviews, questionnaires, observations, brainstorming, use cases.</p>
<p class="rf-detail-row"><span class="rf-label">Output</span>Raw list of needs and expectations.</p>
</div>
</div>
<div class="rf-step is-open" data-index="1" tabindex="0" role="button" aria-label="Requirement Analysis">
<div class="rf-index-row"><span class="rf-dot" style="background:#f1c40f"></span><span class="rf-num">02</span></div>
<h3 class="rf-title">Analysis</h3>
<p class="rf-blurb">Evaluating and analyzing gathered requirements.</p>
<div class="rf-detail">
<p class="rf-detail-row"><span class="rf-label">Goals</span>Resolve conflicts, clarify ambiguities, prioritize requirements.</p>
<p class="rf-detail-row"><span class="rf-label">Output</span>Structured, categorized requirements.</p>
</div>
</div>
<div class="rf-step is-open" data-index="2" tabindex="0" role="button" aria-label="Requirement Specification">
<div class="rf-index-row"><span class="rf-dot" style="background:#3498db"></span><span class="rf-num">03</span></div>
<h3 class="rf-title">Specification</h3>
<p class="rf-blurb">Documenting requirements clearly and unambiguously.</p>
<div class="rf-detail">
<p class="rf-detail-row"><span class="rf-label">Output</span>SRS (Software Requirement Specification) document.</p>
</div>
</div>
<div class="rf-step is-open" data-index="3" tabindex="0" role="button" aria-label="Requirement Validation">
<div class="rf-index-row"><span class="rf-dot" style="background:#9b59b6"></span><span class="rf-num">04</span></div>
<h3 class="rf-title">Validation</h3>
<p class="rf-blurb">Confirming requirements are ready to build from.</p>
<div class="rf-detail">
<p class="rf-detail-row"><span class="rf-label">Checks</span>Correct, complete, feasible, verifiable.</p>
<p class="rf-detail-row"><span class="rf-label">Methods</span>Reviews, inspections, prototyping.</p>
</div>
</div>
<div class="rf-step is-open" data-index="4" tabindex="0" role="button" aria-label="Requirement Management">
<div class="rf-index-row"><span class="rf-dot" style="background:#e74c3c"></span><span class="rf-num">05</span></div>
<h3 class="rf-title">Management</h3>
<p class="rf-blurb">Tracking requirement changes through the project lifecycle.</p>
<div class="rf-detail">
<p class="rf-detail-row"><span class="rf-label">Tools</span>Version control, traceability matrix, change request process.</p>
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});📄 Types of Requirements
Type | Description | Example |
|---|---|---|
✅ Functional | What the system should do | “System should allow login” |
✅ Non-functional | How the system should perform | “Should respond within 2 seconds” |
✅ Domain | Specific to industry or field | “Banking rules for transactions” |
✅ User Requirements | From the user’s point of view | “User should be able to reset password” |
✅ System Requirements | Detailed behavior and interactions | “System shall encrypt all data” |
🔍 Real-Life Example:
You’re building a food delivery app.
Functional: Allow users to place orders.
Non-functional: App must load in < 3 seconds.
User requirement: Easy-to-use interface.
Domain: Compliance with FSSAI standards.