Building Business Success: Web Projects and Technical Architectures
Hello. I am Fernando. I am originally from Spain, but I've lived in Berlin
for the last decade. I am an experienced full-stack web developer with more than
20 years of substantial background building big and small web products. I can help you
build the web product and technical architecture your business needs.
Full-stack senior web developer specializing in Ruby on Rails and associated technologies.
Coming from Spain, I’ve been in Berlin for a long time. I’m a Ruby lover, I draw children’s books, and I’ve been building video games since 2022. I’ve been into Rails since version 0.8, I was one of the organizers of Euruko Barcelona 2009. Matz was wearing his socks when the airplane lost his baggage at Euruko Poland. I had postal correspondence with Why the Lucky Stiff before his disappearance. I’m the creator of fantasy, an open-source library designed to introduce children to programming using Ruby.
I started my programming career at 11 years old using the BASIC language of MSX. I have programmed in Assembler, C, C++, Pascal, Visual Basic, and Java. I moved to Rails after being captivated by its community and culture (make the programmer happy). I also have extensive exposure to Python, JS, C#, and GDScript. I started working for a big company, but most of my career has been in startups. My last adventure was co-founding a company here in Berlin, watching it grow as CTO from 2 employees to 80 in 7 years. I went through investment rounds, technical audits, and finally a successful exit in 2022.
I’ve seen things you people wouldn’t believe. MySQL tables with over 5 billion records. Databases surpassing 16TB. Schema migrations in production that last for days, without downtime. Rails architectures with over 30 services, hundreds of servers, and dozens of databases. AWS monthly invoices over €60K. Setting up 30 web applications running locally to replicate production workflows. Making code changes directly on production servers. Battling against click farms. Debugging JavaScript errors that only occur for users in China.
I am more into Minitest than Rspec, double quotes than single quotes, Authlogic than Devise, “if” than “unless”, long variable names than abbreviations, raw JS than TypeScript, raw CSS than Sass, Bootstrap than Tailwind, REST than GraphQL, VueJS than React, Ubuntu than Debian, nano than vim, Docker Compose than Swarm, and I am afraid of Kubernetes. I prefer Darkmode over Lightmode. I prefer Sundays over Saturdays, rivers over beaches, 2D games over 3D, a good book over a TV series, and silence over music.
My current main interest is integrating AI LLMs (OpenAI) into real-world use cases or business workflows. I’m curious about what the people at Hugging Face are offering and how I can make use of it. I am building an application to leverage an LLM for natural language conversations with my database (RAG architecture), using Ruby and the limited libraries available for this. On my radar for my next research is experimenting with Kamal for deployment orchestration.
I specialize in getting web projects off the ground, guiding them from design concept to fully functional applications. I focus on ensuring production quality while maintaining fast development cycles and rapid feedback loops (deliver fast and iterate). As a senior developer position, I have worked for startups, large corporations, and personal entrepreneurial ventures, contributing either as an individual developer or as part of engineering teams of varying sizes, often taking on leadership roles and influencing architectural decisions.
Most recently, as Co-founder and CTO of a rapidly growing technology company, I was hands-on directing the implementation from scratch of an architecture that now supports more than 100K requests/min and a business of 8 figures yearly—leading the technology decisions of a team of ~80 members. The architecture was acquired in 2022 by an international company.
While my primary expertise lies in Rails applications, I have solid exposure to the entire web development stack.
Over time, I’ve been responsible for a range of tasks, including prototyping, implementing CI-based deployment processes, managing cloud-based servers, front-end development, agile/scrum team management, collaboration with product teams, C-level executive decision-making, microservices architecture implementation, handling high-traffic sites, fraud prevention, performance monitoring, observability and telemetry, autoscaling, managing terabyte-sized databases, down-time-less extensive database migrations, and API design.
I have extensive experience with various languages such as Python, C#, and Java, as well as familiarity with modern JS frameworks like ReactJS and VueJS.
… However, Ruby remains what I enjoy working the most.
Beyond my technical skills, I possess a keen understanding of business needs, demonstrating the ability to make pragmatic decisions and prioritize business growth and success. I excel at collaborating closely with product, sales, and leadership teams, offering alternatives when necessary, and knowing when to make compromises.
Throughout my career, I’ve had the privilege of working alongside incredibly talented individuals from whom I’ve learned and grown. I owe much of my knowledge and skills to the exceptional teams I’ve been a part of and the broader open-source and web development communities, particularly those centered around Ruby.
Right now I was doing my exit interview at Latana (Dalia Research), and the interviewer asked me something like,
"What was the best thing about your time at Latana?". I said I was very grateful to have had the opportunity to work with Fernando.
Fernando is a great engineer who managed to build a great architecture that could handle thousands of requests,
huge data volumes, and multiple development teams working in parallel. Fernando has a good balance between speed and quality of development. During my work in Latana, Fernando got several projects up and running in a very short time, all thanks to his intelligence and his ability to find low hanging fruits. It's important to mention, that he was equally (or even more) contributing to the codebase, despite him being a CTO of the company. I remember how he rewrote one of the most important components of the system over weekend in order to optimise it :)
But more than his hard skills, I'm inspired by the way Fernando cares and respects the people he works with. Fernando felt when I needed
help and never refused it, even if it interfered with his priorities. Another of Fernando's exceptional traits is appreciating the work of others.
Fernando always noticed the achievements of others and publicly expressed his appreciation for them.
I had the honor and pleasure to work closely with Fernando for several years and I’m convinced that he is the most talented Engineer I’ve ever met. At that time he was the CTO of the company I joined and I could witness him building an impressive and complex distributed architecture from the ground up, an architecture that scaled flawlessly over the years up to millions of users sessions through several microservices and API integrations with third party partners. His talent in designing an elastic resilient and versatile system from the very start was what made possible for the company to keep growing exponentially and expand their business without technical constraints.
He is a well rounded engineer, he’s a passionate rubyst and a true talent in full stack development with Rails, but he is also able to jump into every technology and learn it in no time.
From design to hands-on coding up to infrastructure and operations, Fernando was the main driver of every technical solution of the company and a reference and inspiration for every employee inside and outside of the technical department.
He has an impressive talent for finding effective technical solutions to every kind of business requirement or issue and when designing software his style is clean, effective and simple. Through Fernando I learned the value of always being 100% committed to finding the most simple yet effective solution for every requirement. Instead of showcasing his talent through over-engineering or choices of hyped but unnecessary technologies, his main focus was always on delivering features that carry business value in the most agile, simple and maintainable way. You can always trust Fernando to deliver what the business needs, in the most effective way possible.
He was a very loved and appreciated leader in our company, his leadership style is direct and radically honest, Fernando is never afraid of speaking his mind or engaging in a difficult conversation if there’s an issue to solve.His authenticity has always inspired respect and admiration among his coworkers. At the same time his approachability and sense of humor make every interaction with him extremely enjoyable.
Above anything else, I consider him the most important mentor I had in my professional life. His ability and passion to transmit knowledge clearly, as well as an incredible amount of patience and dedication to the mentor role made possible for me and other developers joining the company to learn and grow immensely.
No matter the kind of problem or necessity, Fernando is always 100% committed to helping and delivering real value and I’m sure that this will be of immense benefit to every project or company he will work with.
I can recommend Fernando as a very experienced software architect and tech leader.
He has very good business knowledge and always pushes to understand product and business needs before offering a technical solution. As a product manager, I was always happy to have him as a sparring partner because he could meaningfully challenge given assumptions and help to find the easiest way to test them.
Fernando is also a very talented software architect, the core system that he developed at Dalia proved itself to be scalable and easy to maintain. Fernando always thinks holistically about the system and tries to foresee future changes, at the same time he is very pragmatic and strives for simplicity. The combination of these traits allows him to create the best solutions for the business.
Fernando also is a great person to work with. He is honest and direct and at the same very empathetic and cheerful.
Fernando is probably the most gifted and complete engineer I have ever worked with. When I joined Dalia he was the one-man engineering team, handling everything from frontend, backend to DevOps. During that time he not only maintained the platform but built new features that allowed the company to grow from a few hundred to millions of users.
Fernando combines his excellent engineering skills with a holistic view of the product he is working on. He does not only think in features and tickets but has a keen interest and ability to understand the context of his work. This character trait makes him an invaluable asset to any team as he can really bridge the gap between technology and business.
Fernando has a curious and creative mind and is always trying out new technologies and ways to approach a problem. However, when it comes to building a solution he will not make any compromises and always choose the technology that best fits the problem - he is 100 % results driven.
I have personally benefited greatly from Fernando’s leadership and mentorship qualities. When I joined Dalia as a junior data scientist he always dedicated time to share his technical knowledge with me, even in hectic situations. He has a great way of challenging people to improve themselves and their work. When you present your ideas to Fernando you know that they will be better and more refined afterwards.
Apart from that Fernando has a great character and humor which make him very easy to work with. He has a natural way of creating a great environment for the people around him. I remember many moments where he defused a stressful or tense situation with a funny remark or joke.
Fernando was essential to the team and contributed significantly to the success of our company. He has a very strong work ethic and unparalleled analytical and problem-solving skills.
Fernando is dedicated, self-motivated, methodical, and very capable. He had the vision to see the benefits and the passion to turn that into a competitive advantage for Dalia Research GmbH. I could always depend on him to set the best example as CTO at Dalia Research GmbH.
Fernando is one of the most insightful and effective engineers and engineering leaders I have ever worked with. He constantly strives to get the best possible understanding of the business needs of the product and then turns them into software at a breath-taking speed.
A lot of people preach an "agile" or a "lean" approach to building products but Fernando actually lives those principles. He is always on the lookout for the simplest way to test an idea or a hypothesis and constantly pushes the people around him to do the same. But even when the time comes to make something complex and technically challenging he is there to translate the complicated requirements into easy-to-understand concepts.
The data-reach high-load products and systems that Fernando built at Dalia over 5 years ago practically on his own continue to serve the company and being built upon which is a testament to his ability to create software architectures with a long-term scalability in mind.
He is an incredibly patient listener and communicator and just an extremely nice colleague to be working with.
Fernando has been a key mentor and inspiration for me as a co-founder of Dalia.
There is few people that ever impressed me as much as Fernando - he is someone that radiates curiosity and uniquely combines playfulness and creativity, with extreme professionalism, detail-orientation and precision.
He built an impressive technology infrastructure at Dalia from scratch that enabled us to reach millions of people in 100+ countries in real-time, which allowed us to disrupt the consumer insights world at a rapid pace.
Fernando continuously manages to understand the business challenges that technology is helping solving, and he inspires a team pf 30+ engineers at Dalia to do amazing work.
Fernando is a force of nature, not only with his intellect, but also his values and personality.
True to his builder nature, we were building a wooden raft and riding it together on the Spree. Our time together set me up for a great career, and brought me unforgettable memories.
Fernando has been one of the core factors for the success of our main product AppBounty. His technical expertise in combination with his structured
way of approaching new challenges makes him a one man army for Ruby development. Additionally, he is a fun guy to work with. I would always hire him again.
Fernando cares about his job like only a craftsman can do, combining an endless curiosity which makes ...
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Raúl Murciano · Senior Software Engineering Manager at Heroku
Fernando cares about his job like only a craftsman can do, combining an endless curiosity which makes him a quick learner with a
pragmatic point of view to achieve results quickly. In addition he is a great team player and an extraordinary person to have around.
The truth is that meeting and working with Fernando has been a pleasant surprise: He arrived in to La Coctelera Team because he
wanted to learn and he was excited with the project, and after a few months he turned into a vital piece of the team, he has helped us to carry out tasks and really complex implementations, which have shown that this is a great professional and a wonderful person.
Fernando is a highly talented and professional analyst, developer and linux system administrator. He is always looking for the best way to accomplish specifications and deadlines,
and it is a pleasure to have him in our development team. He has worked successfully for Grupo Planeta developing critical projects.
I've had the opportunity and the privilege of working with Fernando on
several projects: Ceac,
Vitra ...
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Francisco Muñoz · Chief Digitalisation Officer at INPACS GmbH
I've had the opportunity and the privilege of working with Fernando on
several projects: Ceac,
Vitra and AdialOffice. On any of it he has been a key piece for the success
of the project thanks to his involvement and commitment with each project, his
technical skills for development, his contributions for improve it, and his
continuous concern with the satisfaction of the final user once the project
is ongoing.
One of the best things end of 2010 was Fernando joining to work with us
for a few months - on a professional level he immediately provided great value
to our team, on a personal level he was a great guy to have on the team. We'll
miss him lots and would recommend him to any future employer.
