Quality Throughout the Software Development Lifecycle

Metadata

Field Value
Diagram title Quality Throughout the Software Development Lifecycle
Related chapter Chapter 4 — Quality Throughout the Software Development Lifecycle
Part Part I — Foundations of Modern Software Quality Engineering
MQE-BOK domain Domain 1 — Foundations of Modern Software Quality Engineering
Diagram type Lifecycle flow
Skill level Foundation
Model status Original MSQE lifecycle teaching framing; not an ISO or IEEE process definition
Version 0.1.0
Status Draft
Author MSQE Project
Last updated 2026-08-08

Purpose

Show where quality engineering happens: from idea and discovery through operation and learning. The visual emphasises lifecycle coverage and the presence of useful evidence at every activity.

Learning Objectives

After studying this diagram, the reader should be able to:

  • identify lifecycle points where a Quality Engineer can influence a decision; and
  • explain why operational learning must inform future discovery and planning.

Diagram Source

This Mermaid representation follows Chapter 4's modern software delivery lifecycle. It deliberately focuses on where quality work occurs; Chapter 5 separately explains the Continuous Quality Loop and when evidence changes decisions.

Diagram

flowchart TB
    Idea[Idea and discovery]
    Requirements[Requirements]
    Design[Architecture and design]
    Development[Development]
    Verification[Verification]
    Deployment[Deployment]
    Operations[Operations]
    Learning[Learning]
    Evidence[Relevant quality activities and evidence at every lifecycle activity]

    Idea --> Requirements --> Design --> Development --> Verification --> Deployment --> Operations --> Learning
    Learning -. informs future work .-> Idea
    Evidence -. supports .-> Idea
    Evidence -. supports .-> Requirements
    Evidence -. supports .-> Design
    Evidence -. supports .-> Development
    Evidence -. supports .-> Verification
    Evidence -. supports .-> Deployment
    Evidence -. supports .-> Operations
    Evidence -. supports .-> Learning

Textual Interpretation and Accessibility

The main path names the lifecycle activities: idea and discovery, requirements, architecture and design, development, verification, deployment, operations, and learning. The dotted evidence node applies to every activity, not only verification. The dotted arrow from learning to idea shows that lifecycle work is iterative and that an operational finding should influence a future decision.

Component Description

Lifecycle activity Typical quality contribution
Idea and discovery Clarify customer outcomes, consequences of failure, and initial uncertainty.
Requirements and design Make quality expectations, trade-offs, testability, and observability explicit.
Development and verification Produce focused implementation and integration evidence.
Deployment and operations Introduce change safely, observe customer impact, and recover from unexpected conditions.
Learning Turn evidence into a change to future requirements, design, or delivery practice.
  • Chapter 1 — What Is Modern Software Quality Engineering?
  • Chapter 5 — Shift Left, Shift Right & Shift Everywhere
  • Chapter 6 — Systems Thinking for Quality Engineers

Diagram Review Checklist

  • Lifecycle coverage is distinguished from the Continuous Quality Loop.
  • The model does not require a linear delivery method.
  • The Mermaid source provides an accessible textual representation.