Smilen Lyubenov

Full Stack Developer

Full-stack developer with experience in startup, product, and service companies. Skilled in visualizing complex data, optimizing system performance, and maintaining scalable architecture. Strong background in team collaboration, project planning, and mentoring.

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Skills

Front-end

TypeScript

JavaScript

React

Angular

Jest

Vitest

HTML

CSS

Back-end

PHP

Next.js

NestJS

Laravel

MySQL

PostgreSQL

Node.js

Postman

Tools

Docker

AWS

JIRA

Cloudflare

Git

Linux

Figma

Claude Code

Cursor

Professional Experience

Full Stack Developer

June 2024 - July 2025

Dermatic Health - Boston, MA, USA

Delivered 60% of codebase for three client applications built from scratch, ensuring smooth user experience.
Developed 50% of backend APIs and integrated third-party identity provider for secure authentication.
Owned and enhanced core system enabling users to create complex custom forms for efficient data collection.
Researched and developed appropriate technologies to optimize app functionality and scalability.
Integrated AI-generated reports into frontend, enhancing data insights for users.
Led migration to React Native, boosting mobile app performance and user engagement.
Collaborated with architects, data scientists, and product managers to ensure high-quality application delivery.

Senior Fullstack Developer

February 2019 - May 2024

AtScale - Boston, MA, USA

Owned core integration tools connecting AtScale and third-party systems for seamless data communication.
Maintained and optimized backend functionality, improving system responsiveness by 20%.
Performed database maintenance and migrations using ORM frameworks, enhancing data reliability.
Created test plans and implemented automated CI/CD workflows, speeding up deployment cycles by 30%.
Led code reviews, improved workflows, and mentored junior developers.
Partnered with Product Owners and managers to translate requirements into technical features.
Collaborated cross-functionally with Engineering, DevOps, QA, and Data Science teams.
Acted as Deputy Team Leader, ensuring uninterrupted project delivery during leadership absences.
Facilitated Agile ceremonies, driving team coordination and sprint success.

Full Stack Developer

January 2017 - September 2018

IOIO.tv - Sofia, Bulgaria

Developing data APIs and optimizing system structure
Reduced build time by 15% through system deployment distribution
Integrating external services

Co-founder & Full Stack Developer

October 2017 - December 2023

Web4U - Sofia, Bulgaria

Building user-friendly client-side interfaces for 10+ projects.
Developing eCommerce web applications and CRMs using the MVC design pattern.
Participating in project planning and estimations.
Communicating with clients.
Designing front-end, back-end, and databases.

Education & Certifications

Education

Telerik Academy

Software Development Certification

January 2018 - February 2019

Technical University of Varna

Bachelor's, Computer Science

September 2013 - September 2017

Certifications

Meta UI/UX

Meta React Advanced

Meta React Native

EU Operational Program - Software Development

Recommendations

Director of Operations @ Linville Law Group

Elizabeth Morales-Ramos, MBA

Elizabeth was senior to Smilen but didn't manage Smilen directly • October 1, 2025

I had the opportunity to bring Smilen onto our team at Linville Law Group when we identified the need for deeper Salesforce development expertise. As the Director of Operations, I oversee the firm's broader operations, and Smilen has been working closely under our Director of Data, Jaclyn, to ensure our database and Salesforce environment run efficiently and remain compliant. From day one, Smilen impressed us with his attention to detail and strong problem-solving skills. He has played a key role in integrating Salesforce with our vendors, supporting them in navigating the Salesforce API, and creating clear documentation that has greatly improved the ease of our integrations. Beyond that, he has strengthened our system reliability by developing backup and management strategies, improved API security, and supported version updates with careful test refactoring. What I appreciate most is that Smilen doesn't just deliver "quick fixes." He takes the time to understand the larger picture, which has helped us better identify our long-term needs. Thanks to his contributions, we've made significant improvements that go beyond incremental updates and move us toward long-term progress. Smilen is not only technically skilled but also collaborative, reliable, and forward-thinking. He would be a tremendous asset to any team looking to go beyond surface-level improvements and make meaningful strides in Salesforce development.

Architect @ Dermatic Health

Trey Hoover

Trey managed Smilen directly • January 15, 2025

I had the pleasure of working with Smilen at Dermatic Health and was consistently impressed by his dedication and accountability. His thoughtfulness and attention to detail were evident in every solution he delivered. Smilen is proactive and always eager to grow—whether by learning new skills or stepping in to tackle challenges before they become issues. His initiative and strong work ethic made a significant impact on our team's success. Beyond his technical expertise, Smilen's positive attitude and collaborative approach make him a fantastic teammate. I highly recommend him to any team looking for a driven and solutions-oriented professional.

Mathematician and Frontend Architect @ AtScale

Martin Antonov

Martin managed Smilen directly • June 15, 2022

Smilen is an extremely reliable and hard-working developer. He takes on the most difficult of tasks, works quickly and efficiently and produces clean code. It has always been a pleasure, having him on team!

Let's Work Together

Based in Atlanta, GA. Available for full-time opportunities and consulting projects.

📧 web@greensmil.com

Professional Experience

Full Stack Developer

June 2024 - July 2025

Dermatic Health - Boston, MA, USA

Delivered 60% of codebase for three client applications built from scratch, ensuring smooth user experience.
Developed 50% of backend APIs and integrated third-party identity provider for secure authentication.
Owned and enhanced core system enabling users to create complex custom forms for efficient data collection.
Researched and developed appropriate technologies to optimize app functionality and scalability.
Integrated AI-generated reports into frontend, enhancing data insights for users.
Led migration to React Native, boosting mobile app performance and user engagement.
Collaborated with architects, data scientists, and product managers to ensure high-quality application delivery.

Senior Fullstack Developer

February 2019 - May 2024

AtScale - Boston, MA, USA

Owned core integration tools connecting AtScale and third-party systems for seamless data communication.
Maintained and optimized backend functionality, improving system responsiveness by 20%.
Performed database maintenance and migrations using ORM frameworks, enhancing data reliability.
Created test plans and implemented automated CI/CD workflows, speeding up deployment cycles by 30%.
Led code reviews, improved workflows, and mentored junior developers.
Partnered with Product Owners and managers to translate requirements into technical features.
Collaborated cross-functionally with Engineering, DevOps, QA, and Data Science teams.
Acted as Deputy Team Leader, ensuring uninterrupted project delivery during leadership absences.
Facilitated Agile ceremonies, driving team coordination and sprint success.

Full Stack Developer

January 2017 - September 2018

IOIO.tv - Sofia, Bulgaria

Developing data APIs and optimizing system structure
Reduced build time by 15% through system deployment distribution
Integrating external services

Co-founder & Full Stack Developer

October 2017 - December 2023

Web4U - Sofia, Bulgaria

Building user-friendly client-side interfaces for 10+ projects.
Developing eCommerce web applications and CRMs using the MVC design pattern.
Participating in project planning and estimations.
Communicating with clients.
Designing front-end, back-end, and databases.

Recommendations

Director of Operations @ Linville Law Group

Elizabeth Morales-Ramos, MBA

Elizabeth was senior to Smilen but didn't manage Smilen directly • October 1, 2025

Architect @ Dermatic Health

Trey Hoover

Trey managed Smilen directly • January 15, 2025

Mathematician and Frontend Architect @ AtScale

Martin Antonov

Martin managed Smilen directly • June 15, 2022