Lorenzo Duran — Senior Software Engineer

Expertise in Full Stack Web, Back-End Web.

Last verified on May, 2026

Core Skills

Bio Summary

Senior Software Engineer with 11+ years building scalable web applications using JavaScript/TypeScript, React, Node.js, and Express. Expertise in designing high-performance RESTful APIs, improving data retrieval by 35% and reducing response times by 30%. Strong database experience (PostgreSQL, MySQL, MongoDB, DynamoDB) with proven optimization gains. Skilled in TDD with Jest and Mocha, achieving 90%+ coverage and reducing defects. Experienced in Agile, CI/CD, microservices, serverless architecture, and mentoring engineers.

Technical Skills

Programming Languages	JavaScript, TypeScript
JavaScript Frameworks	Express, Node.js, React
Databases & Management Systems / ORM	AWS DynamoDB, MongoDB, MySQL, PostgreSQL
Cloud Platforms, Services & Computing	AWS, Azure
Amazon Web Services	AWS DynamoDB, AWS SAM
Methodologies, Paradigms and Patterns	Agile, microservices, MVC, Observer, OOP, TDD
Collaboration, Task & Issue Tracking	Atlassian Confluence, Atlassian Trello, Jira
Deployment, CI/CD & Administration	CI/CD, GitLab CI
QA, Test Automation, Security	Code Review, Cypress, Jest, Mocha
Virtualization, Containers and Orchestration	Docker
Version Control	Git, Github Actions
SDK / API and Integrations	GraphQL, RESTful API
Soft Skills	Mentor Aptitude

Work Experience

Senior Software Engineer - ScienceSoft (RESTful API and Backend Services Development)

Duration: Jan 2023 – Present
Summary: Development of scalable backend services and RESTful APIs to optimize communication between front-end and back-end systems, improve data processing efficiency, and refactor legacy systems for better maintainability and scalability.
Responsibilities:

Designed and developed RESTful APIs to integrate front-end and back-end systems.
Built scalable backend services using Node.js and Express.
Implemented unit testing with Jest and Mocha to ensure high code coverage.
Participated in code reviews and CI/CD pipelines for quality integration and deployment.
Refactored legacy systems using MVC and Microservices design patterns.
Collaborated in agile environment including sprint planning and retrospectives.
Mentored junior engineers on best practices.
Maintained and optimized PostgreSQL and MongoDB databases.
Researched and implemented new technologies to stay current with industry trends.

Technologies: JavaScript, TypeScript, Node.js, Express, PostgreSQL, MongoDB, Jest, Mocha, RESTful APIs, MVC, Microservices, CI/CD, Agile

Senior Software Engineer - Unqork (Full-Stack Web Application Development)

Duration: Jul 2017 – Dec 2022
Summary:

Development and optimization of full-stack web applications using React and Node
js, focusing on improving user satisfaction, API performance, and code maintainability with design patterns and TypeScript

Responsibilities:

Developed full-stack web applications using React and Node.js.
Designed and optimized REST APIs for faster data retrieval.
Applied design patterns such as Singleton and Factory to improve code maintainability.
Utilized TypeScript to enhance type safety and code quality.
Conducted unit testing and implemented Test Driven Development (TDD).
Collaborated with engineering team to design and launch new features based on customer feedback.
Assisted in integrating MongoDB to enhance system flexibility and scalability.

Technologies: JavaScript, TypeScript, React, Node.js, MongoDB, RESTful APIs, Singleton, Factory, TDD, Jest, Mocha

Software Engineer - Yeti (Dynamic Web Applications and API Development)

Duration: Jun 2013 – Jun 2017
Summary: Building dynamic web applications and maintaining RESTful APIs to improve user experience and data flow, while optimizing database queries and collaborating with cross-functional teams to enhance product features.
Responsibilities:

Built dynamic web applications using JavaScript and React.
Designed and maintained RESTful APIs for smooth client-server data flow.
Optimized MySQL queries to improve database performance.
Participated in code reviews to improve code quality.
Collaborated with designers and product managers to launch features increasing customer retention.

Technologies: JavaScript, React, MySQL, RESTful APIs

Education

University of Texas
Bachelor of Science in Computer Science
Sep 2008 – Mar 2013

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