Senior Full-Stack Engineer
React.js, Node.js, TypeScript, APIs, and reliable production systems.
I'm Gabriel Fernandez, a Senior Full-Stack Engineer with 17+ years of experience building web applications and APIs with TypeScript, React.js, Next.js, Node.js, and NestJS.
My recent work spans end-to-end product engineering across web applications, APIs, and operational systems — shipping features, building integrations, improving reliability, mentoring developers, and delivering production software that holds up under real-world operations.
Toronto, Canada
Open to remote full-time opportunities.
About
I build product systems that stay understandable and dependable as they grow.
My focus is modern full-stack product work with React.js, Node.js, TypeScript, and APIs. I work across frontend, backend, and delivery concerns, and I care about clear architecture, maintainable code, and shipping software that teams can safely build on.
In practice that means shaping solutions with product and design, implementing features, improving integration boundaries, writing and reviewing code carefully, and supporting production after release.
The kinds of systems I've built include:
- Web applications and APIs: Product features and backend services for day-to-day business workflows.
- Integrations and operational tooling: Webhooks, background jobs, retries, and API integrations that keep systems dependable.
- Operational and internal systems: Admin tools, workflow platforms, reporting systems, and business-critical product operations.
Teams usually rely on me for:
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End-to-end ownership from discovery through production delivery
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Reliable systems work around APIs, queues, retries, CI/CD pipelines, and operational workflows
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Clear communication, strong code review, and mentoring support for other developers
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AI-integrated product workflows and infrastructure automation (Docker, CI/CD, Terraform) for faster, safer delivery
Selected work
Recent systems and product work
A few examples that show React, Node.js, APIs, integrations, and reliable delivery in real operating environments.
Valor Distributions
Led end-to-end delivery of a headless storefront and the backend services behind it. Built Node.js services processing 2,000+ webhook events daily with idempotency and retries, stabilized systems to 99.9% uptime, and implemented CI/CD pipelines that doubled release speed while mentoring 7+ engineers.
Built Node.js services processing 2,000+ webhook events daily across 18+ workflows with idempotency and retries.
Stabilized systems to 99.9% uptime and implemented CI/CD (GitHub Actions + EKS/Terraform) that doubled release speed.
Mentored 7+ engineers, introduced automated testing that reduced regressions by 50%, and cut onboarding time in half.
React
TypeScript
Node.js
NestJS
PostgreSQL
Redis
Docker
Terraform
GitHub Actions
Solutis Tecnologias
Led modernization of a large, SLA-driven government platform from Java to TypeScript/Node.js services and React apps. Built APIs, dashboards, and reporting flows for mission-critical operations supporting 100+ daily users with 100% SLA compliance across multiple contracts.
Built APIs, dashboards, and reporting flows for mission-critical operations, meeting 100% SLA compliance.
Automated repetitive workflows, reducing manual actions by 50% and speeding up response time across high-volume queues.
Led a 6-person team and mentored junior engineers into production-ready contributors, cutting onboarding from 8 weeks to 1.
TypeScript
Node.js
React
PostgreSQL
MongoDB
REST APIs
Real-time Reporting
Youtaf
Led development of a service marketplace platform, owning frontend architecture and API clients across React and Vue with TypeScript. Built secure payment integrations, managed a 5-person team, and optimized infrastructure to reduce costs by 80% while improving performance by 30%.
Built secure payment flows (PayPal, PagSeguro) with SDKs and webhooks, reducing payment failures by 60%.
Created an API client library that cut partner integration time by 8 weeks, accelerating onboarding.
Tuned containerized deployments to reduce infrastructure costs by 80% and improve page load time by 30%.
React
Vue.js
TypeScript
Node.js
MySQL
Docker
REST APIs
Payment Integrations
How I work
What teams can expect from me
I fit best where product delivery, engineering quality, and operational reliability all matter.
End-to-end ownership
I work across discovery, implementation, release, and production support rather than treating delivery as only frontend or only backend work.
Reliable product systems
I pay close attention to integration boundaries, operational workflows, tests, safe releases, and the kinds of production details that reduce surprises later.
API and integration depth
A lot of my strongest work sits where products meet external systems: APIs, webhooks, background jobs, retries, AI-driven workflows, and the internal tools that keep operations moving.
Steady collaboration
I like working closely with product, design, and other engineers, and I bring a calm review style with mentoring support when teams need senior guidance.
Core technologies
Technologies I use most for product engineering and backend delivery
The stack below reflects the tools I use most often for React, Node.js, API, and operational systems work.
Get in touch
Hiring for a senior React/Node engineer?
If you're hiring for a senior full-stack role focused on React, Node.js, APIs, and reliable product delivery, I'd be glad to connect. Recruiters, hiring managers, and product teams are all welcome to reach out.
contact.me.gabriel.fernandez@gmail.com
+1 647 563 9688
You can also find me here: