I like building things that still work five years from now.
I'm Yohan Hernández, a senior full stack software engineer. I build websites, online stores and digital products end to end, and the person who answers your messages is the same one writing the code.

I'm from Cuba, and I've made my living from software for 13 years. I didn't start with screens but with what sits underneath them: my first years were in IT security in the banking sector, dealing with networks, servers and backups that had to be restored when something failed. That's where I learned that the parts nobody sees are the ones holding everything up.
Once I realized I could build things instead of just protecting them, I moved to the web and never looked back. Since then I've worked for companies in the United States, Spain, Ecuador and France, and I've usually joined projects someone else had started. Some could be carried forward with confidence. Others had to be rebuilt because nobody dared touch them. The difference was rarely the technology. It was the decisions made in the first few weeks.
Today I work as an engineer at QA-BIT, and in my own time I take on direct clients and build products like Stockvenza. That's why I only take on a few projects at once: I'd rather give each one the attention it deserves than fill up my calendar.
What you get working with me
No account managers or project managers in between. Technical questions get answered the first time, and changes of direction get settled in one conversation.
I build with version two in mind, not just version one. What's small today can grow without a rewrite.
The code, domain and service accounts are yours from day one. If someone else takes over tomorrow, nothing depends on me.
You're not paying for overhead, offices or middle layers, just the work. Every quote is tailored to the scope.
How I work
- 01Read first, then change
Before touching a line of an existing project, I go through all of it and note what it's made of and what's been sitting untouched.
- 02Simple first
No building for a million users when there aren't ten yet. Architecture grows with the product. I explain how in how to design software architecture that won't die in 2 years.
- 03Technology with a track record
Mature tools with active communities for whatever can't fail. The experimental stuff goes only where it genuinely adds something.
- 04Nothing reaches production untested
Changes are tested away from the live site. Only what has already worked somewhere else reaches your website or store.
- 05Every decision explained
In business terms and in writing, so you can decide without needing to code.
Where I've been
- 2025 – presentQA-BIT (Spain)
Software engineer at the agency, plus my own projects in my spare time.
- 2023 – 2025AGL Tech Solutions (US)
Front-end tech lead. A platform that builds AI sales assistants for any website, plus apps for events.
- 2022 – 2023Kynsoft (Ecuador)
Management systems: payment integration and appointment booking for a public institution, and migrating a course-management system off Odoo in two months.
- 2020 – 2022BFS Tracking System (US) and QA-BIT (Spain)
A freight and transport management system, a bus-trip booking engine and custom WordPress sites, including one for a public employment agency.
- 2013 – 2020From security to the web
IT security in the banking sector, webmaster for a media outlet writing my own WordPress plugins, and a complete WooCommerce store for TalenCuba (France).
What I build with
University of Informatics Sciences (UCI), 2013
Web development follows me home, honestly: I enjoy sketching out products and building pages just to see how they turn out. When the laptop closes, I play baseball, watch soccer, and when there's time, a game of chess or a movie. Chess, come to think of it, isn't far from my job: whoever thinks two moves ahead wins.
Shall we talk about what you want to build?
Send me a message about what you have today and what you'd like to have. You'll get a reply from me, not an autoresponder, and an honest answer on whether I can help or who would do it better.