The Essence of Software Development and Engineering: Lessons from Levi's Jeans and Power Plants

In 1853, during the California gold rush, Levi Strauss turned unsold canvas into hundreds of pairs of trousers, creating the world‑famous Levi's denim brand.

Levi’s fortune from jeans proved that a simple product can become a lasting success.

When people ask the author what he does, he answers "software engineering" and often receives the reply, "Can you develop an app for me?" He now uses the Levi’s story to illustrate what software engineering really means.

Engineering is the application of mathematics, empirical evidence and scientific, economic, social, and practical knowledge in order to invent, innovate, design, build, maintain, research, and improve structures, machines, tools, systems, components, materials, and processes.

Software engineering addresses how to do software development effectively, borrowing methods, experiences, and knowledge from science, economics, sociology, and everyday practice.

First, what is software development?

The Essence of Software Development

Software development is simply the process of creating software, but unlike manufacturing a car—once a car leaves the factory it cannot be remelted—software undergoes many "re‑melting" cycles before release.

Cars are shipped as finished products; apps on your phone are updated repeatedly, each version having passed through a production line again. The production line in software corresponds to compilation, packaging, and continuous integration (CI). Most of the time developers are designing rather than assembling; the actual “workers” are compilers, CI systems, and other automated tools.

Therefore, managing programmers like factory workers is misguided; they need to create, not merely assemble pre‑made parts, making traditional waterfall management uncomfortable.

So how should software development be done? The answer lies in choosing the right "pair of jeans" for the job.

The Essence of Software Engineering

A story from a training session illustrates the concept: an elderly instructor placed a kettle, alcohol lamp, water, a blade, a small motor, and a bulb on a table, boiled water, generated steam, turned the blade, and lit the bulb—demonstrating a simple power plant.

He explained that depending on the fuel (coal, natural gas, nuclear, water), the plant becomes a coal‑power plant, gas‑power plant, nuclear plant, or hydro plant. The complexity of real power projects serves two purposes: safety and efficiency.

In software engineering, "safety" is interpreted more broadly as "quality".

Because most of the development process is in the design phase, a deterministic approach—fixed requirements, complete design, and 100% execution—does not work. Agile methods such as Scrum, Kanban, extreme programming, and continuous integration were created to build highly adaptable systems that can handle uncertainty.

Efficiency in software is achieved not by rigid standardization but by rapid, coordinated transitions between high‑efficiency states.

Quality is illustrated with two anecdotes: a barber’s varying service for the same price and Toyota’s high reliability despite a higher failure probability after the warranty period. Quality means keeping deviation small within defined standards.

In software, establishing standards and continuously checking deviations—through CI, test‑driven development, coding guidelines, and automated deployments—ensures quality. Continuous improvement is also required; testing alone only checks deviations, it does not raise quality.

Architectural approaches such as micro‑services, SOA, testability, and deployability further support both efficiency and quality.

---

The author finally shares a link to a friend’s article on software development and invites readers to follow the "devopshub" WeChat public account for more DevOps and R&D integration information.