Stephen Garcia — Senior Full-Stack Engineer

Expertise in Full Stack Web, Cloud Infrastructure Engineer.

Last verified on May, 2026

Core Skills

SQL

5 yr.

Bio Summary

Senior full-stack engineer with 6+ years of experience delivering scalable B2B platforms using React, Node.js, and SQL (PostgreSQL/MySQL).
Expertise in designing and optimizing REST and GraphQL APIs with OAuth 2.0 authentication, improving backend response times by up to 40%.
Proficient in deploying micro-applications on Google Cloud Platform (Cloud Run, Cloud SQL) ensuring 99.9% uptime and automated scaling.
Strong background in computer science with Master’s and Bachelor’s degrees from University of Belgrade.
Skilled in CI/CD automation, webhook integrations, and resolving critical production issues, reducing release cycles by 30% and support tickets by 25%.

Technical Skills

Programming Languages	JavaScript, TypeScript
JavaScript Frameworks	Node.js, React
JavaScript Libraries and Tools	React Hooks
Databases & Management Systems / ORM	MySQL, PostgreSQL, SQL
UI Frameworks, Libraries, and Browsers	CSS3, HTML5
Cloud Platforms, Services & Computing	GCP
Amazon Web Services	AWS CloudTrail
Google Cloud Platform	Cloud run
Deployment, CI/CD & Administration	CI/CD
Virtualization, Containers and Orchestration	Docker, Terraform
Version Control	Git
SDK / API and Integrations	GraphQL, OAuth, RESTful API, Shopify API
Platforms	Shopify

Work Experience

Senior AI Engineer - DeepL (Customer-facing micro-applications and backend APIs)

Duration: June 2023 - Present
Summary:

Development and delivery of customer-facing features and backend APIs using React, Node
js, and GraphQL, deployed on Google Cloud Platform to support secure integrations for over 10,000 users with high availability and scalability

Responsibilities:

Delivered weekly customer-facing features using React, Node.js, and GraphQL.
Designed and implemented REST and GraphQL APIs with OAuth 2.0 authentication.
Built and maintained SQL schemas (PostgreSQL, MySQL) and optimized queries.
Deployed micro-applications on Google Cloud Platform (Cloud Run, Cloud SQL).
Integrated webhooks and event-driven flows for real-time data synchronization.
Collaborated with CTO to define requirements and iterate on prototypes.
Owned end-to-end feature delivery including deployment and monitoring.
Debugged and resolved critical race conditions and implemented robust error handling and logging.
Implemented fine-grained IAM policies to secure cloud resources.

Technologies: React, Node.js, GraphQL, REST APIs, OAuth 2.0, PostgreSQL, MySQL, Google Cloud Platform, Cloud Run, Cloud SQL, webhooks, Git

Software Engineer - Revolut (Production features and API development for financial platform)

Duration: April 2022 - May 2023
Summary: Development and deployment of production features and APIs for a high-scale financial platform serving over 100,000 active users, including migration of legacy APIs to GraphQL and integration with third-party services.
Responsibilities:

Developed and shipped production features using React, Node.js, and TypeScript.
Built GraphQL and REST endpoints with secure OAuth 2.0 flows.
Designed and optimized PostgreSQL schemas for analytics dashboards.
Implemented responsive UIs with HTML5, CSS3, and React.
Automated deployment pipelines on Google Cloud Platform using Git and CI/CD.
Created webhook handlers for real-time transaction notifications.
Led migration of legacy REST APIs to GraphQL.
Investigated and resolved bottlenecks in order processing service.
Maintained collaborative workflows with Git branching and pull requests.
Supported e-commerce integrations including Shopify Admin API and Billing API.

Technologies: React, Node.js, TypeScript, GraphQL, REST APIs, OAuth 2.0, PostgreSQL, HTML5, CSS3, Google Cloud Platform, Git, CI/CD, Shopify Admin API, Billing API, webhooks

Backend Developer - HTEC Group, Serbia (B2B SaaS platform backend development)

Duration: September 2018 - March 2022
Summary: Backend development and maintenance of REST APIs and backend services for B2B SaaS platforms and e-commerce clients, focusing on API security, performance optimization, and cloud deployment.
Responsibilities:

Built and maintained REST APIs with Node.js and JavaScript.
Designed relational schemas and wrote complex SQL queries for PostgreSQL and MySQL.
Implemented OAuth 2.0 authentication and authorization flows.
Developed backend services integrating payment gateways and order management systems.
Optimized backend performance by profiling and refactoring SQL queries.
Created and maintained API documentation and error handling patterns.
Supported frontend teams with GraphQL schema design and resolver implementation.
Debugged and fixed webhook delivery issues ensuring idempotency.
Deployed services on Google Cloud Platform and managed infrastructure with Docker and Terraform scripts.
Used Git for collaborative development and code reviews.

Technologies: Node.js, JavaScript, REST APIs, OAuth 2.0, PostgreSQL, MySQL, GraphQL, Google Cloud Platform, Docker, Terraform, Git

Education

Master's degree, Computer Science
University of Belgrade
2018 - 2020
Bachelor's degree, Computer Science
University of Belgrade
2014 - 2018

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