About David
Senior Software Engineer with 20+ years of experience in backend development on the JVM, specialized in Java/Spring, reactive systems and microservices, with strong focus on SOLID design, refactoring legacy platforms and performance. You have worked across banking, retail, energy, travel, education and public sector projects, designing and implementing greenfield architectures, improving existing systems and leading POCs, always applying TDD, clean code and cloud‑native best practices. I'm also active in AI and developer productivity tooling, building my own POCs with Python, Langchain, CrewAI and Ollama, and frequently mentoring teams, reviewing code and introducing modern practices in CI/CD, observability and documentation.
Spanish
Native or bilingual
English
Fluent
French
Conversational
Remote only
Primarily works remotely
Experience
- ApiumhubSenior Software EngineerFebruary 2021 - March 2023 (2 years and 1 month)Barcelona, SpainHotel booking management project: distributed micro-monolith system for booking purposes. All backend projects were proxies between SAP/CMS servers & web/apps clients. Code reviewer, mentoring and a lot of refactoring legacy code towards functional, KISS, SOLID, and YAGNI. Methodologies & architectures: MVC, Hexagonal, TDD, DDD, Scrum, Jira, CI/CD, GitLab, Docker.• - Java: Maven, Spring, Java11 , Redis• - Clojure: Lein, Clojure, Elasticsearch, Mysql, Redis.
- Energy ToolsSenior Software EngineerApril 2020 - January 2021 (9 months)Terrassa, CT, SpainMaven/Java/Spring/MVC/REST-API/Mongo, Angular2, Gitlab, Scrum.Refactoring java legacy code: removing technical debt & bad practices, applying SOLID/MVC, etc. (decoupling layers & components, abstraction, complexity, generics, complex hierarchy…).Tomcat memory leak fixing (closing resources, better implementation for Garbage Collector, etc).Sonar+TDD architecture set up (unit & parallel integration testing: selenium, junit5, mockito).Complete cache impl. refactor/fix with tomcat parallel deployment (created Infinispan GitHub issue).AWS S3 resilient implementation for different environments (dev, staging, production).CI/CD: Gitlab workflow improvements (MR, pipes, releases) & release automation via bash vs GitLab API.Readme’s & Wiki: created (inexistent/obsolete) technical documentation.Issue fixing, new functionality implementation, UX improvements.
- ASM Web ServicesSenior Software EngineerApril 2018 - September 2019 (1 year and 5 months)Viladecans, CT, Spain1 . Scala projects: dynamic-pricing-platform project (sbt, jquery/ui, play, scala, akka actors, mssql, redis)• - Integration tests architecture, development & dockerization (JUnit, Selenium, Scala).• - Project refactor removing: complexity, layers/libs coupling, duplicated code (Scala, ScalaStyle, Sonar, good practices).• - POC serialization with Avro, ProtocolBuffers, ...Transversally to projects & technologies: application of SOLID principles with refactorings, mentoring for junior roles, creating inexistent documentation (GitLab wiki & readme's).
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Education
- FPII Informática de Gestión (Vocational Training II- Information technologies). Formación Ocupacional MicroelectrónicaFPII Informática de Gestión (Vocational Training II- Information technologies). Formación Ocupacional Microelectrónica
- Curso UML(Centro de formación BIT2000Curso UML