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David (Valera) Valera melendez

Senior Full-Stack Developer

David Valera melendez
Maikammer, Germany

Experience

Nov 2023 - Present
2 years 3 months

Senior Full-Stack Developer

AL-KO Geräte GmbH

  • Architected and executed complete enterprise migration of legacy hosting infrastructure to AWS Cloud platform for an international e-commerce network with 22 dedicated online shops.
  • Optimized and improved existing OXID eShop platform across 22 country-specific domains, significantly improving load speeds and user experience through advanced performance optimization techniques.
  • Implemented comprehensive AWS infrastructure with CloudFormation for automated deployments, RDS Aurora database clusters, OpenSearch analytics, Docker containerization, and auto-scaling mechanisms for traffic handling.
  • Developed full-stack solutions with backend PIM/CRM integration for multilingual product management and frontend internationalization with country-specific routing, currency handling, and localized user experiences.
  • Collaborated in a 6-developer team for an enterprise e-commerce platform serving 22 international markets.
  • Technologies: AWS CloudFormation, OXID eShop, Docker, RDS Aurora, OpenSearch, Auto-Scaling, PIM/CRM Integration, Internationalization, Performance Optimization, E-Commerce.
  • Achieved successful architecture and execution of complete enterprise migration and dramatic improvements in load speeds and user experience across all domains.
Sep 2022 - Jun 2023
10 months

Senior Frontend Developer

Deutsche Bahn

  • Developed an innovative Kanban board system for real-time train status display and management with Angular enterprise architecture.
  • Built a modern frontend for live tracking of all trains in the German rail network from scratch, handling massive data streams and complex visualization requirements.
  • Implemented robust fail-safe frontend mechanisms to ensure continuous operation of rail infrastructure with automatic recovery protocols.
  • Collaborated with a 16-developer team in the Plan Korridor department, maintaining high code quality through comprehensive Jasmine unit tests.
  • Focused 100% on Angular-based frontend engineering for railway operations and infrastructure management.
  • Technologies: Angular, TypeScript, Jasmine, Enterprise Architecture, Real-Time Systems, Kanban Boards, Data Visualization, Fail-Safe Systems, Live Tracking.
  • Delivered enterprise-grade frontend solutions for transport systems with zero critical incidents.
Oct 2021 - Aug 2022
11 months

Senior Software Architect

ADVOCATE SOFTWARE

  • Led software architecture and served as team lead for a modern cloud-based law firm management platform from scratch using Angular, NestJS, Ionic, and Electron.
  • Designed an end-to-end encrypted security framework with multi-layer authentication, secure data transmission, and compliance with legal industry standards.
  • Created elegant UI/UX tailored for attorneys, including a web-based document editor, case management workflows, client portals, and comprehensive firm management tools.
  • Managed a cross-platform development team of 10 frontend and backend developers to deliver advanced legal software with real-time communication systems.
  • Implemented internal chat system using @nestjs/websockets for real-time collaboration between attorneys.
  • Technologies: Angular, NestJS, Ionic, Electron, @nestjs/websockets, TypeScript, Security Frameworks, Cloud Platforms, UI/UX Design.
  • Successfully delivered the complete law firm management platform and implemented an end-to-end encrypted communications system meeting legal compliance standards.
Jan 2021 - Sep 2021
9 months

Senior Frontend Developer

HZD

  • Developed high-security frontend applications for government sector clients, including the 'Elster' tax office system, using Angular and Bootstrap CSS with BFSG accessibility compliance.
  • Built a secure frontend for police authorities enabling encrypted information transmission with multi-layer authentication and advanced privacy measures.
  • Created frontend interfaces for housing allowance forms, implementing government security standards, encrypted data transmission, and regulatory compliance frameworks.
  • Ensured highest security clearance levels for sensitive government data, enforcing strict data protection regulations and audit trails.
  • Technologies: Angular, Bootstrap CSS, TypeScript, BFSG Accessibility, Government Security, Encrypted Transmission, Multi-Layer Authentication, Compliance Frameworks.
  • Delivered secure tax office and police communication frontends with zero security incidents and full accessibility compliance.
Jan 2020 - Dec 2020
1 year

Senior Full-Stack Developer

BIONTECH

  • Architected and developed an enterprise CRM management system from scratch with Angular, Bootstrap CSS frontend and Java Spring Boot backend for pharmaceutical operations.
  • Created comprehensive REST APIs for importing XML documents from SAP, enabling seamless data integration between legacy systems and the new CRM platform.
  • Built the PharmaPilot system including customer management, invoice processing, order management, and inventory control tailored to pharmaceutical workflows.
  • Collaborated with a team of 12 senior developers in an agile environment, conducting rigorous code reviews and automated testing.
  • Designed scalable system architecture for complex pharmaceutical data workflows and regulatory compliance.
  • Technologies: Angular, Java Spring Boot, Bootstrap CSS, REST APIs, SAP Integration, XML Processing, CI/CD, Agile Development.
  • Successfully delivered the PharmaPilot CRM system and seamless SAP integration for real-time data synchronization in healthcare operations.
Jan 2017 - Dec 2019
3 years

Full-Stack Developer & UI/UX Designer

CONCEPT STUDIO

  • Developed secure card ordering frontend with React and Tailwind CSS and Java Spring Boot backend for a banking client.
  • Built a claims reporting and management system from scratch for an insurance client.
  • Created an employee management system with Laravel backend and advanced check-in/checkout functionalities for a CRM client.
  • Implemented technology stack selection, system architecture planning, and scalable NestJS backend on AWS.
  • Contributed to UI/UX design initiatives and provided Swagger API documentation for all projects.
  • Technologies: React, Tailwind CSS, Java Spring Boot, NestJS, Laravel, AWS, Docker, MySQL, Swagger, Microservices.
  • Delivered a scalable microservices architecture on AWS, reducing deployment time by 70% and zero security incidents in production.
Jan 2014 - Dec 2016
3 years

Full-Stack Developer

IT-CAP STUDIO

  • Developed a comprehensive travel booking platform with Laravel backend and Angular frontend featuring advanced reservation management, hotel listings, and booking workflows.
  • Created professional UI/UX designs and responsive interfaces for travel agency platforms.
  • Built mobile applications with Ionic framework for cross-platform booking functionalities.
  • Integrated third-party APIs for hotel listings, flight bookings, and real-time price updates.
  • Optimized database performance for complex booking queries and multi-criteria search operations.
  • Technologies: Laravel, Angular, PHP, JavaScript, MySQL, Ionic, HTML5, CSS3, Bootstrap, REST APIs.
  • Improved booking conversion rates by 60% and reduced booking errors by 80% through automated test frameworks.
Jan 2012 - Nov 2013
1 year 11 months

Java Backend Developer

United Realty Ltd

  • Developed backend systems with Java and Spring Framework for enterprise real estate management platforms.
  • Built RESTful APIs for property listings, price comparison tools, and agent management features.
  • Implemented MySQL database solutions for real-time market analyses and user management.
  • Designed scalable architecture for high-volume real estate data processing and integrated MLS and third-party APIs.
  • Technologies: Java, Spring Framework, MySQL, REST APIs, Hibernate, Maven, Apache Tomcat.
  • Delivered scalable backend handling 10,000+ listings and improved property search response times by 60%.
Jan 2011 - Dec 2011
1 year

Junior PHP Engineer

INTERBANK

  • Developed and maintained banking web applications with PHP, MySQL, and JavaScript for secure financial transactions.
  • Implemented payment processing modules and transaction validation systems for thousands of daily transactions.
  • Collaborated on database design and optimization for financial data processing and storage.
  • Ensured compliance with banking security protocols and conducted code reviews.
  • Technologies: PHP, MySQL, JavaScript, HTML/CSS, Apache, SVN.
  • Launched secure online banking interfaces processing millions of dollars daily with zero security incidents.

Summary

Comprehensive summary of my 10+ years of experience in developing enterprise applications, cloud migration, and team leadership as a Senior Full-Stack Developer.

Skills

My Development Approach Is Based On Proven Software Development Principles And Modern Technologies. I Place Great Value On Clean Code, Test-driven Development, And Continuous Integration.

  • Agile Development With Scrum/kanban
  • Test-driven Development (Tdd)
  • Clean Code Principles
  • Microservices Architecture
  • Devops And Ci/cd
  • Code Reviews And Pair Programming

Languages

Spanish
Native
German
Advanced
English
Advanced
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