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I am a detail-oriented software engineer with 2+ years of experience designing, developing, and maintaining backend software solutions in fintech. I specialize in Java and Spring Boot, RESTful API development, and collaborative Agile delivery. I enjoy troubleshooting production systems, participating in code reviews, and delivering high-quality software in fast-paced environments. I’m comfortable working independently while contributing effectively to distributed teams to meet project goals and deadlines. Outside of work, I’m passionate about music and technology—playing guitar and drums, exploring practical uses of large language models, traveling, and long-distance running. I’m excited to continue growing my skills in distributed teams and contributing to impactful fintech solutions.…I am a detail-oriented software engineer with 2+ years of experience designing, developing, and maintaining backend software solutions in fintech. I specialize in Java and Spring Boot, RESTful API development, and collaborative Agile delivery. I enjoy troubleshooting production systems, participating in code reviews, and delivering high-quality software in fast-paced environments. I’m comfortable working independently while contributing effectively to distributed teams to meet project goals and deadlines. Outside of work, I’m passionate about music and technology—playing guitar and drums, exploring practical uses of large language models, traveling, and long-distance running. I’m excited to continue growing my skills in distributed teams and contributing to impactful fintech solutions.

Celso del Castillo II

Back-End Developer, Full Stack Developer, Web Developer, +2

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I am a detail-oriented software engineer with 2+ years of experience designing, developing, and maintaining backend software solutions in fintech. I specialize in Java and Spring Boot, RESTful API development, and collaborative Agile delivery. I enjoy troubleshooting production systems, participating in code reviews, and delivering high-quality software in fast-paced environments. I’m comfortable working independently while contributing effectively to distributed teams to meet project goals and deadlines. Outside of work, I’m passionate about music and technology—playing guitar and drums, exploring practical uses of large language models, traveling, and long-distance running. I’m excited to continue growing my skills in distributed teams and contributing to impactful fintech solutions.…I am a detail-oriented software engineer with 2+ years of experience designing, developing, and maintaining backend software solutions in fintech. I specialize in Java and Spring Boot, RESTful API development, and collaborative Agile delivery. I enjoy troubleshooting production systems, participating in code reviews, and delivering high-quality software in fast-paced environments. I’m comfortable working independently while contributing effectively to distributed teams to meet project goals and deadlines. Outside of work, I’m passionate about music and technology—playing guitar and drums, exploring practical uses of large language models, traveling, and long-distance running. I’m excited to continue growing my skills in distributed teams and contributing to impactful fintech solutions.

Available to hire

I am a detail-oriented software engineer with 2+ years of experience designing, developing, and maintaining backend software solutions in fintech. I specialize in Java and Spring Boot, RESTful API development, and collaborative Agile delivery. I enjoy troubleshooting production systems, participating in code reviews, and delivering high-quality software in fast-paced environments. I’m comfortable working independently while contributing effectively to distributed teams to meet project goals and deadlines.

Outside of work, I’m passionate about music and technology—playing guitar and drums, exploring practical uses of large language models, traveling, and long-distance running. I’m excited to continue growing my skills in distributed teams and contributing to impactful fintech solutions.

Skills

Experience Level

Expert

Expert

Expert

Expert

Expert

Expert

Expert

Language

English

Fluent

Work Experience

Software Engineer at Maya Philippines, Inc. (formerly Paymaya)

September 1, 2023 - Present

Designed, developed, and maintained backend software applications using Java and Spring Boot, supporting financial workflows and high-volume transaction processing. Collaborated with team members to define, design, and deliver new backend features, contributing to incremental and production-ready releases. Troubleshot and debugged issues across development and production environments, implementing fixes and improvements to enhance application stability and performance. Built and maintained RESTful APIs, ensuring performance, quality, and responsiveness of backend services. Improved critical API performance by 40% through Redis pipeline optimization and efficient serialization techniques. Participated in peer code reviews, contributing to best practices, maintainable code, and consistent engineering standards. Documented technical designs, implementation details, and operational considerations to support maintainability and knowledge sharing. Worked effectively in an Agile, distributed