Software engineer and team lead, passionate about distributed systems, backend architecture, and the intersection of traditional finance and blockchain.

Currently leading distributed teams at ioBuilders while actively building backend systems for the tokenization of financial instruments, bridging legacy financial infrastructure with blockchain networks and digital asset platforms.

Previously developed software for 200k+ daily active users at Amazon, contributing to Kindle across Android, e-reader firmware, and iOS.

Experience

Team Lead & Backend Software Engineer @ ioBuilders · May 2023–Present · Remote

Leading distributed teams building backend systems for tokenization of financial instruments and tokenized deposits.

  • Built nine microservices from scratch supporting digital asset platforms at production scale.
  • Implemented a DynamoDB retry strategy that significantly reduced Internal Server Errors.
  • Led CloudFront integration overcoming infrastructure limitations imposed by external customers.
  • Tech: Go, Java, PostgreSQL, DynamoDB, Redis, Kafka, gRPC, AWS, Kubernetes.

Software Development Engineer @ Amazon · Mar 2020–Mar 2023 · Madrid, Spain

Shipped features to millions of Kindle users across Android, e-reader firmware, and iOS.

  • Led Android development of a Bluetooth-based setup feature used by 200k+ users/day.
  • Built key features for Kindle Scribe, Amazon’s first e-reader with handwriting support.
  • Conducted interviews and led on-call rotations across all three roles.

Software Engineer @ Deloitte Digital · Jan 2018–Mar 2020 · Madrid, Spain

Delivered web portals and backend services for large enterprise clients across international teams.

  • Developed enterprise portals with Oracle WebCenter Sites and Spring Framework.
  • Automated deployment pipelines with Jenkins and integrated PWA capabilities into existing portals.
  • Built analytics dashboards with Google Tag Manager and Klipfolio.

Software Engineer Intern @ YBVR · Aug–Dec 2017

Built a multimedia content manager for internal and external services, and contributed to live broadcasting infrastructure for sports events.

Education

BSc in Software Engineering · Universidad Complutense de Madrid · 2013–2018

Final project: Multi-platform recipe search and management app · Grade: 9/10.

Skills

Languages: Go, Java, Kotlin, Swift, Objective-C, Python, JavaScript, C++, C

Databases: PostgreSQL, SQL Server, MySQL, DynamoDB, Redis

Messaging & Streaming: Apache Kafka, RabbitMQ, gRPC

Infrastructure: AWS, Kubernetes, CloudFront, Jenkins, GitLab CI

Practices: Hexagonal architecture, event-driven design, RESTful APIs, GraphQL, microservices, on-call, technical ownership

Recommendations

“Carlos is one of the most consistently inquisitive and curious Software Engineers I have worked with, able to take on a variety of challenges in a wide range of development environments and succeed as a consistent, reliable, and friendly teammate. From iOS to Android to Linux based devices I witnessed Carlos consistently contribute to the team, take on difficult tasks others avoided, and deliver meaningful results. Carlos became known as our data expert and helped deliver critical insights along with building new experiences for our customers.”

Sam Donnelley, Senior Engineering Manager @ Amazon

“I had the chance to work closely with Carlos on one of our company’s projects and what I can remember is the quality of the code and documentation that Carlos produced. Each discovery made by his investigations was the subject of serious documentation from which the whole team could benefit. Having Carlos on your team is a privilege.”

Raymond Pokorny, Senior SQA Analyst

“Carlos and I worked at Amazon in the same team for the past 6 months. He is a bar raiser on documentation, clean code and maintainability of code bases. He can work on solving hard problems in different platforms, from iOS and Android, to software for dedicated devices. He is a great team mate, always available to teach new things to his colleagues and with a great sense of ownership.”

Melissa Muñoz, Software Engineer @ Amazon

See more in my LinkedIn profile