The Hidden Link Between Toyota’s Shusa and Today’s Product Engineer in Software

In software circles, we’re seeing a growing interest in the Product Engineer — someone who blends engineering skill with product intuition. On platforms like productengineer.org, this role is celebrated as the evolution of software engineering in product-led organizations.

But this idea isn’t new. In fact, Toyota was already doing this in the 1980s.

Meet the Shusa (主査), Toyota’s legendary Chief Engineer — and arguably the original product-minded engineer.

🧑‍💻 What’s a Product Engineer in Software?

In modern software development, a Product Engineer is someone who:

• Writes code with a deep understanding of user needs.

• Works closely with designers, PMs, and business stakeholders.

• Takes ownership of product outcomes, not just feature delivery.

• Thinks in systems, balancing trade-offs in UX, scalability, cost, and time-to-market.

It’s a hybrid role — equal parts builder, problem solver, and product thinker.

🚗 What Did Toyota Do Differently?

In Toyota’s vehicle development model, each car (like the Camry or Prius) was led by a Shusa — a cross-functional technical leader who:

• Owned the vision and delivery of the entire product.

• Navigated engineering, manufacturing, customer needs, and business trade-offs.

• Operated outside of functional silos, orchestrating the whole system.

• Made final decisions on what features mattered and how they were delivered.

The Shusa wasn’t a project manager. They were a technical leader with product responsibility — just like what we’re trying to create with Product Engineers in software.

So What Can We Learn in Software?

1. Stop Treating Engineers Like Code Monkeys

When engineers understand why a feature matters, they make better decisions. Like the Shusa, Product Engineers should be exposed to the customer early and often.

2. Create Space for Outcome Ownership

Rather than handing engineers a fixed spec, involve them in defining the problem. Think “build the right thing” — not just “build it right.”

3. Design Teams Around Cross-Functional Thinking

Toyota teams reported to both their functional heads and to the Shusa. In software, a Product Engineer should collaborate across product, design, infrastructure, and even marketing to ensure alignment.

4. Trust Engineers With Business Trade-offs

Too often, business decisions are hidden from developers. But Product Engineers (like Shusas) need to balance technical debt, velocity, and value — and they can, if you trust them.

💡 Real-World Software Example

At many startups and tech companies (like Stripe, Airbnb, or Netflix), the best engineers don’t just code — they ship impact. They know how to say:

“This API change saves support 10 hours/week.”

“This onboarding redesign increases conversion by 15%.”

“This latency improvement improves user engagement.”

That’s not just great engineering — it’s Shusa thinking in software.

Software Is a System, Not a Stack

Toyota’s Shusa showed us the power of technical leaders owning the product end-to-end. In software, we often think of systems in terms of microservices, components, and layers — but a real system includes the user, the business, and the team.

By embracing the Product Engineer mindset, we build great products :

• With care.

• With purpose.

• With the customer in mind.

Maybe it’s time to bring a little bit of Shusa mindset into our tech teams.