Freelance Backend Developer

Information technology, automation & software development

Get in Touch

About Me

Who I Am

I'm a passionate backend developer with a focus on process automation, custom system design, and software architecture. Specialized in VBA, Python, and Java, with hands-on experience in building sales systems, inventory management solutions, and RESTful APIs.

What I Do

My goal is to join projects where I can apply my knowledge of automation, clean architecture, and object-oriented programming, contributing to operational efficiency, system scalability, and strategic decision-making through well-structured and high-impact technological solutions!

Why Work With Me

I bring a combination of technical expertise, problem-solving abilities, and communication skills to every project. I'm committed to continuous learning and staying updated with the latest technologies and best practices in backend development.

My Projects

SyncTube API

Development of a lightweight REST API for real-time multimedia content synchronization, aimed at collaborative interaction between users. Features include input validation, music persistence & download, and data control via JSON.

Python JSON FastAPI

POS System in Java (Work in Progress)

Modular system design using DDD, Clean Architecture, and JavaFX. Implements local persistence with SQLite and design patterns such as Repository, Factory, Observer, and others.

Java

JavaCodeBox

Utility package for automation and parallel processing in Java. Includes experimentation with concurrency, aspect-oriented programming (AOP), and structural design patterns.

Java

Knowledge & Experience

Technical Skills

Java

90%

Python

75%

Kotlin

20%

MySQL

90%

Git

85%

Programming Languages: Java (OOP, Concurrency, AOP), Python, VBA, Kotlin (basic)


Databases: MySQL/PostgreSQL, SQLite, Microsoft Access


Frameworks / Technologies: JavaFX, Swing, FastAPI, Java EE, Spring Boot, Javalin


Software Architecture: Clean Architecture, DDD, Hexagonal Architecture, MVC


Version Control & Tools: Git, GitHub (dependency management with Maven)


Automation & Office Integration: Macros, Office Scripting, Excel Dashboards


System Design: POS systems, inventory management, medical appointment systems, REST APIs


Languages: Native Spanish and intermediate English (B2)

Technical Training & Acquired Skills

Backend Development & Software Architecture

About

Solid foundations in OOP, DDD, MVC, Clean Architecture, and Hexagonal Architecture. Design of scalable systems (POS, REST APIs, utilities). Proficient with design patterns: Factory, Observer, Singleton, Strategy, and others.

Java & Kotlin

About

Development with Java SE, Swing, and JavaFX for GUI applications. Experience with concurrency, AOP, synchronized collections, and multithreading. Introductory knowledge of Kotlin and functional programming concepts. API development using Javalin/Spring Boot for POS systems (in progress).

Python and Task Automation

About

Automation of administrative tasks using Python and VBA. File handling, data structures, exception control, and web scraping. API development with FastAPI and JSON data manipulation.

Databases & SQL

About

Database design and SQL queries using MySQL/PostgreSQL, SQLite, and MS Access. Advanced query filtering, relational modeling, report generation, and custom data exports.

Education

Freelancer – Process Automation and Systems Management

November 2023 – Present

Automated administrative workflows using VBA and Python. Developed sales, purchasing, and inventory systems for small and medium-sized businesses. Built interactive dashboards, advanced forms, and custom macros in Excel. Acted as an external consultant on Java EE and REST API projects. Provided technical support and guidance to clients for optimizing and maintaining their systems.

Professional Excel (University Technical Degree – Ongoing)

About

Creation of interactive dashboards, custom macros, and advanced forms. Automation of repetitive tasks in inventory and sales systems. Integration of Excel with databases and advanced data analysis techniques!

Get In Touch

Contact Information

carlosemiliogranadaperez@gmail.com

+52 55 8172 7493

MEXICO