Technical co-founder vs founding engineer: what is the difference?

A technical co-founder is a founder with shares who owns the technology of the company. A founding engineer is one of the first employees and builds within the decisions of the founders. The technical co-founder makes those decisions and answers for them to the other founders and to investors.

The two seats side by side

What a technical co-founder does

The business founders win customers and raise money. The technical co-founder decides what gets built and on which systems. This founder builds the first version of the product and leads the developers who join after the first round. A technical co-founder carries the risk of the company together with the other founders.

What a founding engineer does

A founding engineer writes code for most of the week. A founder or a CTO sets the direction. The employment contract names a salary, often with options on shares. When the team grows, the founding engineer takes part in the interviews with new developers.

Where the CTO title fits

CTO is a job title. In many young companies the technical co-founder carries it. A company that fills the position after a funding round hires a startup CTO as an employee. That CTO decides how the product is built and who builds it. In a small team the CTO writes code as well.

Which of the two a team needs

A team in which somebody already decides the technology hires a founding engineer. A team without that person looks for a co-founder or a CTO.

Before a technical partner signs, founders settle eight questions for a technical co-founder. Four of them concern both seats:

1. What exists already: a prototype, code from a freelancer, a spreadsheet?
2. Who holds the code, the domain and the cloud accounts today, and do they move to the company?
3. Who decides on the product, the technology, hiring and spending?
4. How many hours a week do the founders and the new partner put in, and from which date?

Shares, vesting and the shareholder agreement belong to the founders and their lawyer.

My work in the technical seat

I am an IT expert for data platforms in Frankfurt. For more than twenty years I have built software and led the teams behind it.

At a Frankfurt fintech I was Head of Decentralized Finance and Node Operations, then Chief Information Officer with procuration. I led business-critical teams and held the IT budget. I ran blockchain nodes in several data centers and wrote the concept of a real-time market data product.

At a company that built a global real estate database I was developer and CTO. I programmed the websites and the databases, hired people and led the teams.

In several due diligences I examined IT systems, teams and products, for buyers and for sellers.

Today AI agents speed up my work. On a client’s platform Claude and Codex work under the same rules as the developers. Agents and developers there have created more than 300 RESTful API endpoints and made more than 8,000 commits. A person confirms production changes.

I take on technical roles like these as a freelancer or as a permanent employee.