About

John Contreras

Founder, CTO, and product engineer.

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The story

I've been shipping software for more than fifteen years. I started as an engineer and kept getting pulled toward the whole problem: the product, the people, the business. Along the way I've been the head of product, the VP, the CTO, and the founder.

In 2014 I co-founded MoveSpring, a corporate wellness platform, and Stridekick, a fitness social app. At MoveSpring I wrote the first line of code, helped grow the company past 30 people, and took it from idea to profitability to an acquisition by Reward Gateway in 2022. I stayed on through 2024 to lead the product integration. Stridekick is still running today.

I've also led architecture and development in healthcare, sports betting, ecommerce, and finance. Different industries, same job: turn a messy business problem into software that holds up.

Today I build my own products, write about what I'm learning, and work with a small number of founders and teams as a fractional CTO or hands-on builder. AI is part of every step. It doesn't replace judgment. It amplifies it.

Years shipping software
15+
Companies co-founded
2
Acquisition
1
Users reached
3M+

Experience

What I bring

Leadership

  • Fractional CTO
  • Hiring and team building
  • Product strategy
  • M&A integration

Engineering

  • TypeScript
  • React and Next.js
  • React Native
  • Swift and SwiftUI
  • GraphQL
  • Docker

AI

  • AI-assisted engineering
  • Agents and skills
  • LLM product integration
  • Workflow automation

Building now

  • Avocado. AI-powered nutrition tracking.

    avocado.app
  • Thesis. Lyric videos, timed to the word.

    thesis.app
  • Custom Heroes. Personalized storybooks starring your kid.

    customheroes.ai
  • Unboxery. Compare supplements by what's in them.

    unboxery.com
  • Doodle Name. AI business naming with live domain checks.

    doodle.name

What I believe

Code is cheap. Engineering isn't.

AI made writing code nearly free. Knowing what to build, how to structure it, and how to keep it simple is where the value moved.

Read Is Coding Dead?

Choose the stack for the product.

React Native was the right call for a startup that needed speed. With AI shrinking the cost of code, native is worth another look.

Read React Native Was the Right Call

Teach your tools how you work.

Capture your patterns once, as skills and conventions, and every session after that starts smarter.

Read Making Sense of AI Agent Skills

Hiring, building, or stuck on a big call?

Whether it's a role, a project, or a second opinion, I'm happy to talk it through.