David

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[open contact info](look above in the "contact info" section)
David Guseinov
Java Backend Engineer | Spring Boot | Microservices | SQL | IoT & Smart
[open contact info](look above in the "contact info" section) Systems | Open to EU and Ukraine Remote Roles
LinkedIn Summary
I am a Java Backend Developer with hands-on experience building
Top Skills commercial software solutions for retail stores, cafés, and service
businesses.
Java
I specialize in designing reliable backend systems that automate
Web Development business processes, manage data efficiently, and integrate with hardware
and smart systems. My background combines software development,
IoT business automation, and IoT integration (KNX, Buspro), which allows me
to approach problems from both technical and operational perspectives.

Languages My core stack includes Java, Spring Boot, REST APIs, and MySQL. I
focus on writing clean, maintainable code and building scalable
Ukranian (Native or Bilingual) architectures.

English (Limited Working) In addition to development, I have experience as a Computer
Science and Mathematics teacher, which strengthened my analytical
thinking and ability to explain complex concepts clearly.

Currently based in Spain and open to backend opportunities
across the EU and Ukraine(remote).

Experience
Smart Home Systems Engineer (KNX / Buspro)

January 2025 - November 2025 (11 months)

• Designed and implemented smart building automation
systems for residential and commercial properties

• Configured and programmed KNX and Buspro
controllers

• Integrated lighting, HVAC, security, and multimedia
systems

• Worked with system architecture, wiring topology, and
device configuration Page 1 of 3

• Diagnosed and resolved integration issues between
hardware and software components

• Collaborated with contractors, electricians, and clients
to deliver customized automation solutions

• Improved energy efficiency and operational convenience
through automation scenarios
 September 2023 - January 2025 (1 year 5 months)

• Taught Computer Science and Mathematics to students
of different levels

• Developed structured lesson plans and educational
materials

• Explained complex technical and mathematical concepts
in a clear and practical way

• Prepared students for exams and олимпиадного
уровня задач

• Mentored students in programming fundamentals and
algorithmic thinking

• Fostered analytical thinking and problem-solving skills

Freelance / Contract
Java Backend Developer (Freelance / Contract)

November 2011 - January 2025 (13 years 3 months)

• Designed and developed backend systems for retail
stores, cafés, and small service businesses

• Built RESTful APIs using Java and Spring (Spring Boot)

• Designed and optimized relational databases (MySQL)

• Implemented business logic for sales management,
inventory tracking, and reporting

• Automated accounting and operational workflows to
improve business efficiency

• Integrated backend systems with POS hardware and
external services

• Refactored legacy code and improved system stability
and performance

• Communicated directly with business owners to gather
requirements and deliver tailored solutions

• Reduced manual accounting time by 40%

• Served 5+ active businesses

• WEB-develop

Computer Science
& Mathematics Teacher