From idea to first customer

A renewable energy startup had a clear vision: make it easy for homeowners to order and install solar panels. They had the industry expertise, the partnerships, and the demand. What they didn’t have was a single engineer.

They came to us with a product idea, some wireframes, and a lot of urgency. The market was moving fast and competitors were circling.

Here’s how we took them from zero to live.

The situation

The founders were domain experts — they knew solar installation inside and out. But they had never built a software product before. No CTO, no engineering team, no codebase. Just a notion doc and a burning need to ship.

They needed everything: a tech stack, a team, a development process, and a path to market. And they needed it yesterday.

What we did

I was part of a three-person engineering team from McKinsey embedded with the startup. My role was twofold: build the product and build the team that would eventually run it.

Phase 1: Setup the foundations

We didn’t start from scratch. Instead of building a custom platform from zero, we picked a flexible CMS as our base and extended it with custom features. This let us move fast without reinventing the wheel.

The first sprint was about getting something working end-to-end. Not pretty, not perfect — just functional enough to validate the flow.

Phase 2: Hire and onboard the team

While the other engineers built, I focused on hiring. We needed to find engineers who could eventually own this codebase without us. That meant looking for pragmatism over perfection, and ownership over experience.

We hired the first engineers, set up their development environment, and walked them through the codebase one module at a time. I trained them not just on the tech, but on how we worked: fast iteration, short feedback loops, ship and learn.

Phase 3: Manage the ecosystem

On top of the core platform, we needed custom apps for external partners — installers, logistics providers, and sales agents. I managed an external agency that built some of these integrations, making sure their output matched our quality bar and timelines.

Phase 4: Hand over and scale

The goal was always to make ourselves unnecessary. Over the next few months we gradually handed over ownership:

• First, the client engineers paired with us on features
• Then, they took over bug fixes and small features independently
• Finally, they owned entire workstreams while we reviewed and advised

By the time we stepped back, the internal team was running the show.

The result

• Went live with a working platform that let customers configure and order solar installations
• Custom landing pages for partners drove customer acquisition across multiple regions
• Scaled country-wide from zero to national coverage
• Internal team hired, trained, and fully owning the codebase within months

The founders went from “we need engineers” to “we are the engineering team.”

What I learned

The fastest path to production isn’t the most elegant architecture — it’s the one that lets you learn what actually matters. A CMS you can extend beats a custom platform you’re still building. Engineers who value shipping over perfection beat brilliant ones who overthink.

But the real unlock was treating team building as a parallel track to product building. Hire early, train continuously, and plan your own obsolescence from day one.