MARCOSMONTERO
Head of Engineering • Founding Engineer
Architecting high-fidelity digital systems from first principles.
As Head of Engineering and Founding Engineer at Fynza, I am architecting the financial backbone of the Experience industry — designing the 0→1 fintech infrastructure that translates booking data into liquidity for Tour Operators across global Booking Systems and OTAs, built on AWS CDK, Turborepo, tRPC, and Prisma at a scale engineered for millions in transaction volume.
Before Fynza I was Founding Tech Lead at Enso Coliving, where I replaced a fragmented legacy stack with a unified PropTech engine handling booking, payments, and verification in one flow — €30,000/month MRR within 30 days of launch.
Beyond technical leadership, my approach is shaped by a fascination for traveling and exploring diverse cultures, broadening my perspective on global technology interaction and fostering unique problem-solving insights. You can explore my selected work and side projects in my portfolio. I also write about these intersections on my blog, where I share technical and personal reflections from my engineering journey.
The Edge
Architecture before the team is hired
The decisions made in week one decide whether the codebase still works at engineer #20. I draw the seams early — adapter layers, canonical data models, IaC from day zero — so the platform survives scope changes, not just the first demo. At Fynza that's AWS CDK, Turborepo, tRPC, and Prisma; at Enso it was Supabase + Next.js holding booking, payments, and verification in one flow.
Pattern recognition over framework worship
Mensa member, but the part that matters is the habit: I look for the underlying shape of a problem before reaching for a tool. Most legacy stacks aren't broken because of bad code — they're broken because someone solved the wrong problem cleanly. I optimize for the right problem first.
Signal over noise
I trained as a sound engineer before I trained as a software engineer. Both jobs reduce to the same thing: cut what's in the way, amplify what matters. I apply it to interfaces (no decorative state), codebases (delete > add), and roadmaps (one bet at a time).
First-engineer pace
First engineering hire at Fynza. Founding Tech Lead at Enso. The job is to ship the first version fast and pick the constraints — review patterns, CI/CD, IaC, SOC2 / ISO 27001 readiness — that make engineer #2, #5, and #20 ship faster, not slower. €30k/month MRR within 30 days at Enso is the version of this I can show on paper.
Fynza
Head of Engineering · Founding Engineer
First engineering hire at a fintech building the financial backbone of the Experience industry. Architecting a 0→1 platform that translates booking data into liquidity for Tour Operators across FareHarbor, Ventrata, Viator, and GetYourGuide.
- Designed a proprietary Adapter layer aggregating global Booking Systems and OTAs into a canonical source of truth for risk evaluation.
- Spearheaded a Turborepo + AWS CDK (IaC) + tRPC + Prisma stack engineered for millions in transaction volume.
- Establishing SOC2 / ISO 27001 technical readiness and leading a specialized external engineering team.
Enso Coliving
Founding Tech Lead / Architect
Replacing a legacy fragmented tech stack, I architected a unified PropTech engine that handled property management, payments, and user verification in a single flow.
- Enabled €30k/month revenue launch within 30 days of rollout.
- Architected a scalable Supabase + Next.js infrastructure supporting rapid expansion.
- Implemented a high-conversion qualifying flow reducing manual ops by 70%.
Mindera
Senior Frontend Architect
Led the digital transformation of enterprise-scale legacy systems into modern React architectures, serving millions of users across international markets.
- Architected the migration of legacy monolithic infrastructures to modern React + TypeScript stacks.
- Drove mobile innovation by leading React Native adoption for strategic client products.
- Established high-standard CI/CD pipelines and component libraries used across multiple global teams.
Nomoko
Senior Frontend Engineer
Pioneered high-performance 3D visualization layers for urban digital twins. Optimized Three.js rendering pipelines to handle massive datasets on the browser.
- Architected 3D visualization layers using Three.js and React Three Fiber.
- Optimized rendering pipelines for large-scale urban spatial data.
- Improved mobile performance by 40% through custom shader optimization.
Cesce
Software Engineer
Developed secure and regulatory-compliant financial interfaces for one of Spain's leading credit insurance agencies.
- Built mission-critical fintech modules with a focus on data integrity and security.
- Collaborated on the modernization of internal risk assessment tools.
- Integrated complex financial APIs with real-time validation layers.
Engineering Philosophy
Code as a Liability
Every line of code is a maintenance burden. I optimize for deletions and lean architectures that prioritize business agility over technical vanity. Simplicity is the ultimate sophistication.
User-Centric Rigor
Performance isn't just a metric; it's respect for the user's time. I build systems that feel instant and reliable under any load, with a focus on perceived performance and accessibility.
