Hi, I'm Celal.
I'm a Backend Software Engineer
I'm a backend software engineer working for Marktplaats, specializing in building scalable backend systems in microservice architecture and refactoring legacy codebases to modern technologies.
Furthermore, I graduated 🎓 in Computer Science at 🏛️T
U Delft
During my studies, I worked on a variety of projects that deepened my passion for building things with code. I love turning ideas into real, working products that people can interact with and enjoy. I'm always open to connect — let’s get in touch 🤝!
About.
I'm Celal Karakoç 👋, a Backend Software Engineer at Marktplaats and a Computer Science and Engineering graduate from TU Delft. Over the past year, I've been working on production backend systems at scale, gaining hands-on experience with distributed services, databases, cloud infrastructure and event-driven systems.
My work has ranged from migrating services from Java and Spring to Scala, improving data retention, reliability, observability, and CI/CD pipelines across backend services. I enjoy working on problems where there’s more to consider than just writing code: understanding how systems behave in production, keeping them maintainable, and finding practical ways to improve their performance, reliability, and operational cost.
I've worked across a variety of technologies including Java, Scala, Spring, Kafka, RabbitMQ, Kubernetes, MySQL, Datadog, Terraform, Thrift, gRPC and a plethora of other technologies. Working in a large production environment has taught me a lot about designing and maintaining reliable services, collaborating across teams, and dealing with the realities of evolving software systems. I'm always interested in learning something new and getting a deeper understanding of the systems I work with.
Before starting my career as a software engineer, I explored a wide range of projects during my studies, from web and backend development to C++, Unity, and a medical hand-simulation project at a TU Delft startup. I also experimented with entrepreneurship by trying to build a company with two friends. Those experiences gave me the freedom to explore different areas of software and helped shape the way I approach new problems today.
When I'm not coding 👨💻, I enjoy cycling 🚲, bouldering 🧗♂️, fitness 🏋, doing city trips ✈️ and watching movies 🎥.
I'm always looking for new challenges and opportunities to learn and grow as a developer. If you're interested in working together or have any other questions, please don't hesitate to get in touch! 🔗
Using currently
Exploring currently
Used in the past
Experience.
Developing and maintaining backend services for Marktplaats’ marketplace platform. Migrated core components from Java/Spring/Hibernate to Scala/ScalikeJDBC, removed deprecated APIs and legacy code across multiple services and improved database and data-retention processes. Worked on migrating services towards k8s and optimized storage cost and query performance reducing the retention period and enabling the deletion of tens of millions of ads without down-time for the end-user. Worked with Kafka and RabbitMQ for event-driven processing, including retry mechanisms and monitoring. Maintained testability and CI/CD pipelines, and worked across Thrift and gRPC APIs. Added Datadog metrics and dashboards for marketplace and media services, improving observability across the image-processing pipeline. Contributed to 120+ merged PRs across 27 repositories, collaborating on changes spanning APIs, infrastructure, databases, and microservices.
Engaging in intensive training programs and earning certifications to strengthen backend development skills. Focusing on building expertise in microservices, Cloud, observability and scalable system design.
I worked 3 years at a clothing store in Rotterdam Centre, providing personalized assistance to customers, enhancing their shopping experience and driving repeat business. My commitment was recognized with the "Employee of the Month" award, highlighting my consistent performance and contribution to the store's success.
I worked at my university as an assistant for varying courses, such as Computer Organisation, Algorithms and Datastructures and Data Mining. I helped with grading students and answering their questions.
Perception Neuron is a cutting-edge motion capture technology developed by Noitom, a leading innovator in the field of motion capture. For my Software Project I, with a group of students, had to help this company with one of their products, called AXIS Neuron for about 3 months.
MaxEncode was a company that I, with two other people, worked on when I was self-employed. We together tried to excel this company from the ground up and ultimately failed doing so. Still, I learned quite a bit, mostly regarding Laravel, and I don't plan on giving up just yet.
Education.
Projects.
This is a repo to show all my Frontend creations on frontendmentor.io. FrontendMentor is a website that simulates real-life working conditions. It gives you a design file and expects you to code it, with all the specifications.
Learn more >
![An image of the [WIP] JellyCash (Client) project.](/_next/image?url=%2Fproject-imgs%2Fjellycash0.png&w=2048&q=75)
![An image of the [WIP] JellyCash (Server) project.](/_next/image?url=%2Fproject-imgs%2Fjellycash1.jpg&w=2048&q=75)
![An image of the Oğuz Bezorgd [WIP] project.](/_next/image?url=%2Fproject-imgs%2Foguz_logo.png&w=2048&q=75){kind=logo}
