Andrés Pedraza Míguez
Senior Java & Kotlin Engineer | Remote Contractor Specialist
Professional Summary
Senior Backend Engineer with over 14 years of experience designing scalable systems, now leveraging a strong hybrid skill set in Java (Backend) and Kotlin (Mobile/Android). Proven track record working as a Remote Contractor for UK-based companies, delivering high-quality solutions in English-speaking environments.
Specialises in Java 21, Spring Boot, and Hexagonal Architecture, with recent hands-on leadership in Android Native (Jetpack Compose) projects. Known for stepping into complex, legacy environments to refactor code, mentor senior peers, and drive delivery. Passionate about software craftsmanship, automated testing, and solving critical business problems across the full stack.
Work Experience
Senior Java Developer (Acting Mobile Tech Lead) at Plexus Tech
Client: Inditex (Zara) | October 2023 – Present | Seville (Remote)
- Dual Role Strategy: Officially hired as a Backend Engineer but proactively took ownership of a critical Android App (Kotlin, Jetpack Compose) to mitigate delivery risks, effectively operating as a Fullstack Lead.
- Mobile Rescue & Architecture: Refactored unstable legacy Android modules, establishing clean architecture patterns and resolving critical production bugs that were impacting Zara's supply chain operations.
- Technical Leadership: Mentored senior team members on modern Kotlin practices and Jetpack Compose, significantly elevating the team's coding standards and reducing technical debt.
- Backend Core: Developed robust microservices using Java 21 and Spring Boot 3, enforcing an API-First strategy: used OpenAPI for mobile clients and AsyncAPI with Kafka & Avro schemas to guarantee type-safe integration with logistics partners.
- Quality Assurance: Enforced strict testing protocols (JUnit, Mockito, Traffic Parrot) across both backend and mobile codebases to ensure stability in a Dockerised Azure environment.
Main Project: Raw Materials (Inditex)
A critical initiative managing the logistics and distribution of raw materials across global Zara warehouses.
Tech Stack: Java 21, Kotlin (Android/Compose), Spring Boot 3, Apache Kafka, Docker, Azure, MongoDB, JUnit, Mockito, CI/CD pipelines.
Senior Java Developer at Brandworkz
February 2017 – August 2023 | London (Hybrid)
- Led the development of a core Java-based API within a multi-tenant microservices architecture for high-profile clients like Boeing, Dr. Martens, and Hitachi.
- Built a complete Reporting module from scratch and developed custom analytics visualizations using Elasticsearch and Kibana.
- Implemented OAuth2 authorisation and significantly enhanced API security with granular user roles.
- Automated deployment pipelines using Bash scripts, CRON jobs, and Jenkins.
- Actively involved in architectural decisions, strategic planning, and onboarding new hires.
Main Project: Brandworkz SaaS
A Digital Asset Management (DAM) platform used globally by enterprise clients.
Tech Stack: Spring Boot, Spring Cloud, Spring Security, AWS (EC2/S3/RDS), Elasticsearch, Redis, PostgreSQL, Swagger, OpenAPI 3, Liquibase.
Freelance Backend Developer (Contractor at Brandworkz)
February 2022 – August 2023 | Remote
- Successfully transitioned from full-time employee to independent contractor, demonstrating strong self-management and reliability in a 100% remote setup.
- Focused on performance optimisations and backend support during critical system upgrades.
Back-end Developer at Locassa Ltd
July 2015 – November 2016 | London (On-site)
- Managed the full software lifecycle: planning, implementation, deployment, and maintenance for multiple client startups.
- Built back-office applications and led client demos and requirement gathering sessions.
- Mentored junior developers and introduced new frameworks to improve development efficiency.
Projects: Ziferblat, Minted, Inkvite, Jarvis, Vesta Fitness, Rounds on Me.
Tech Stack: Spring Boot, Thymeleaf, REST APIs, MySQL, OAuth2, AWS (Elastic Beanstalk, S3, EC2).
October 2014 – May 2015 | Seville (On-site)
- Gathered requirements and authored technical analysis documents for government modernization projects.
- Led configuration, testing, and deployment in integration environments.
Tech Stack: iBatis, Spring, Struts, PL/SQL, Apache Tomcat, Maven.
January 2012 – September 2014 | Seville (On-site)
- Delivered new functionalities for the "HAPR" system (Telematic Authorisation) for the Junta de Andalucía.
- Optimised database performance using advanced PL/SQL scripts.
- Applied Scrum methodology in an agile team environment.
Tech Stack: Hibernate, iBatis, Spring, JSP, PL/SQL, Subversion.
Junior Oracle/Java Developer at Ayesa
April 2011 – December 2011 | Seville (Part-time)
- Developed GUI prototypes and maintained legacy systems for public healthcare and social services projects.
Tech Stack: Oracle Forms, PL/SQL, Hibernate, Spring, JSF.
Skills
- Languages: Java (Expert), Kotlin (Advanced), Dart (Intermediate)
- Core Frameworks: Spring Boot 3, Spring Cloud, Microservices, Hexagonal Architecture
- Data & Messaging: Apache Kafka, MongoDB, PostgreSQL, MySQL, Oracle, Redis, Elasticsearch
- Cloud & DevOps: Docker, Kubernetes, Azure, AWS (EC2, S3, RDS), Jenkins, CI/CD, Git
- Testing & Quality: JUnit 5, Mockito, TDD, Integration Testing
- Other: API-First Design, OpenAPI Generator, AsyncAPI, OAuth2, Liquibase, Gradle
Education
HNC in Administration and Information Technology
IES Punta del Verde, Graduated 2011
- Focused on software development and database management.
- Capstone project combining Java and SQL technologies.