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Full-stack developer with hands-on experience building production-ready web applications using React, TypeScript, Spring Boot, and PostgreSQL. Passionate about clean architecture and fluid user experiences, focused on delivering complete solutions from idea to deployment. Currently pursuing the 6th semester of Software Engineering at the University of Cartagena. Looking for a remote junior or internship role to contribute to real products and grow quickly by working with a team and scalable systems.…Full-stack developer with hands-on experience building production-ready web applications using React, TypeScript, Spring Boot, and PostgreSQL. Passionate about clean architecture and fluid user experiences, focused on delivering complete solutions from idea to deployment. Currently pursuing the 6th semester of Software Engineering at the University of Cartagena. Looking for a remote junior or internship role to contribute to real products and grow quickly by working with a team and scalable systems.

Julián Martínez Espitia

Full Stack Developer, Web Developer, Back-End Developer, +3

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Full-stack developer with hands-on experience building production-ready web applications using React, TypeScript, Spring Boot, and PostgreSQL. Passionate about clean architecture and fluid user experiences, focused on delivering complete solutions from idea to deployment. Currently pursuing the 6th semester of Software Engineering at the University of Cartagena. Looking for a remote junior or internship role to contribute to real products and grow quickly by working with a team and scalable systems.…Full-stack developer with hands-on experience building production-ready web applications using React, TypeScript, Spring Boot, and PostgreSQL. Passionate about clean architecture and fluid user experiences, focused on delivering complete solutions from idea to deployment. Currently pursuing the 6th semester of Software Engineering at the University of Cartagena. Looking for a remote junior or internship role to contribute to real products and grow quickly by working with a team and scalable systems.

Available to hire

Full-stack developer with hands-on experience building production-ready web applications using React, TypeScript, Spring Boot, and PostgreSQL. Passionate about clean architecture and fluid user experiences, focused on delivering complete solutions from idea to deployment.

Currently pursuing the 6th semester of Software Engineering at the University of Cartagena. Looking for a remote junior or internship role to contribute to real products and grow quickly by working with a team and scalable systems.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Intermediate

Intermediate

Language

Spanish; Castilian

Fluent

English

Intermediate

Work Experience

Full-stack Programming Instructor at Self-employed

January 1, 2026 - January 31, 2026

Designed and delivered a structured 4-week online bootcamp on Java and Spring Boot for beginner and intermediate students. Created hands-on labs covering REST APIs, Spring Security, JWT, and CORS, enabling students to deploy secured backend services. Led live sessions with real-time code reviews and curated learning resources, guiding students from fundamentals to building basic CRUD applications.

Design & Programming Instructor (Java & Spring Boot Bootcamp) at Self-employed

January 1, 2026 - Present

Created and delivered a structured 4-week online bootcamp on Java and Spring Boot. Prepared live coding sessions and hands-on labs covering REST APIs, Spring Security, JWT, and CORS, enabling students to deploy first secured backend services. Led live sessions with real-time code reviews and curated learning resources, guiding students from fundamentals to building basic CRUD applications.

Electoral Technology Technician at Registraduría Nacional - Colombia

January 1, 2024 - December 31, 2024

Operated biometric authentication devices to verify voter identities during the 2024 Colombian territorial elections. Ensured accurate and secure registration while handling sensitive personal data under strict confidentiality protocols. Coordinated with electoral staff to resolve incidents quickly and maintain continuous operation of the voting process at assigned stations, reducing identity-verification errors.

Electoral Technology Operator (Biometric Authentication) at Registraduría Nacional - Colombia

January 1, 2024 - December 31, 2024

Operated biometric authentication devices to verify voter identities during the 2024 Colombian territorial elections. Ensured accurate and secure voter registration by handling sensitive personal data under strict security and confidentiality protocols. Coordinated with electoral staff to resolve incidents quickly and maintain continuous station operation.

Freelance Web Developer & Software Engineer at Self-employed

January 1, 2024 - Present

Designed and shipped 5+ full-stack web applications for clients using React/Next.js, TypeScript, and Spring Boot. Delivered responsive landing pages, dashboards, and e-commerce solutions with GSAP animations, improving user engagement. Owned end-to-end delivery: gathered requirements, defined architecture, modeled PostgreSQL/Supabase schemas, implemented REST APIs, and handled production handoff with documentation. Integrated third-party services such as JWT/Auth.js authentication, payments, and external REST APIs to automate manual client processes and reduce operational effort.

Sales Associate & Customer Support at Retail / E-commerce Nacional

January 1, 2023 - January 1, 2024

Managed product catalog, inventory records, and pricing data across in-store and online channels to keep customer-facing information accurate. Supported promotional campaigns and tracked basic metrics to identify best-selling items and adjust stock levels. Provided customer service in Spanish and basic English through multiple channels, improving satisfaction and repeat purchases.