Xavier Mas Leszkiewicz

CEO & Co-Founder at BlueberryBytes

Xavier Mas Leszkiewicz

Technology Leader, Entrepreneur, Software Engineer and Music Producer

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About

Who I Am

Highly strategic technology leader with a proven track record of building innovative solutions. Driven by a methodical approach to problem-solving and a commitment to excellence. Entrepreneur, Software Engineer, and Music Producer with over a decade of experience transforming business challenges into technological opportunities.

Location

Dubai, UAE

Experience

Career Path

CEO & Co-Founder

BlueBerryBytes

November 2024Present

At BlueBerryBytes, I lead the technological vision and execution, driving innovation across multiple projects. My role encompasses architecting scalable solutions, overseeing engineering teams, and ensuring the seamless integration of AI-driven and cloud-native technologies. With expertise in full-stack development, mobile, AI, Big Data, and high-performance backend systems, I design and implement robust infrastructures that power our products. I also work closely with product, marketing, and business teams to align technology with strategic goals, optimizing performance, security, and user experience.

January 2025Present

CTO of BeApolo

January 2025Present

CTO of Dress Up Your infinite wardrobe Website: https://app.dressupstore.it/

Senior Full-Stack Engineer

Lumenalta

September 2024

Delivered high-impact technical solutions as a consultant for enterprise clients. Architected and implemented comprehensive software solutions utilizing React, Ionic, NodeJS, SQL, AWS, and GCP. Collaborated with cross-functional teams to translate complex business requirements into scalable and maintainable code. Provided technical leadership and mentorship to junior developers while ensuring adherence to best practices and coding standards.

Senior Full-Stack Engineer

Elliptic

January 2023

Engineered sophisticated UI and backend systems for blockchain analytics in the cryptocurrency sector. Developed an intuitive application enabling users to navigate and analyze transactions across multiple blockchains including Bitcoin and Ethereum. Implemented dynamic data visualization components to present complex blockchain data in an accessible format. Collaborated with security and compliance teams to ensure adherence to financial regulations while maintaining optimal performance.

Senior Software Engineer

Full on Net (Telefonica)

May 2022

Led the strategic consolidation of LATAM and Spain infrastructure for all IPTV events, resulting in significant operational efficiencies and cost reductions. Architected and implemented a unified system using Python, Java, MongoDB, Kafka, Kafka Streams, Celery, and Behave. Designed and deployed scalable microservices architecture to handle high-volume streaming events across multiple regions. Collaborated with international teams to ensure seamless integration while maintaining service reliability during the transition.

Co-Founder and CTO

Relevanzz

July 2020

Established and led a technology startup as CTO and Co-Founder, gaining comprehensive insight into all aspects of business operations. Directed strategic initiatives across technology, marketing, sales, and business development to drive company growth. Spearheaded the end-to-end product development lifecycle, from conceptualization to market launch. Orchestrated all technical aspects including product design (UI/UX), infrastructure architecture, and software development. Built and managed cross-functional teams while establishing agile development methodologies to ensure efficient product delivery.

Software Engineer - Machine Learning POD

eDreams ODIGEO

July 2019

Architected and implemented robust backend infrastructure to support advanced machine learning initiatives for Europe's largest online travel company. Collaborated closely with data scientists to optimize and deploy ML models into production environments. Designed scalable systems capable of processing and analyzing large volumes of travel data to enhance customer experience. Utilized Java, Python, Docker, Maven, Kafka, Kubernetes, Kibana, and Elastic Search to build high-performance, resilient systems that powered data-driven decision making across the organization.

Java Developer - BI Revamp

eDreams ODIGEO

February 2018

Led the comprehensive revamp of business intelligence systems, utilizing Java, NoSQL, SQL, and Maven to process and analyze large-scale datasets. Assumed end-to-end ownership of the project lifecycle from initial architecture design through production deployment. Engineered efficient ETL processes to transform and consolidate data from multiple sources into actionable business insights. Implemented performance optimizations that reduced data processing time by 40% while improving data accuracy and reliability.

Java Developer and IT Security

SIA Group. Sistemas Informáticos Abiertos

January 2017

Managed critical identity and security infrastructure in a high-stakes government environment, overseeing protection for more than 250,000 user identities. Orchestrated complex application migrations while enhancing security protocols and system performance. Developed and optimized scripts using Oracle Identity Manager to streamline identity management processes. Implemented robust security solutions utilizing diverse technologies including Active Directory, Oracle database, Visual Basic, Siteminder (SSO), Spring, and Struts frameworks to ensure compliance with stringent government security standards.

Education

Academic Background

May 2023

Postgraduate in Quantum Engineering

UPC School. School of Professionals & Executive Development

July 2016

Big Data Management & Analytics

UPC School. School of Professionals & Executive Development

March 2015

Bachelor degree in Audiovisual Systems

UPC. Universitat Politècnica de Catalunya

February 2015

Bachelor Thesis

Technische Universität Berlin

Object Tracking with multiple cameras using real-world coordinates