Senior Java Developer2022 - PRESENTVolvo Cars
Technologies: Java, Spring Boot, Apache Kafka, Kafka Streams, Kafka Connect, Schema Registry, Event Sourcing, Event Driven Development, GitHub Actions
- Developed a set of microservices responsible for managing the subscription backbone for the Volvo Cars company.
- Used Github Actions to ensure code quality, create the binary, and run the application on the Kubernetes environment.
- Contributed to the event-sourcing infrastructure of microservice applications. Kafka was used as the main storage of subcription-related data by leveraging Kafka Streams.
- Created Kafka Connect tasks for synchronizing the Postgres database by using Kafka topics.
Senior Back-end Developer | DevOps2021 - 2022Caravelo
Technologies: Java, Vue, REST, SOAP, API Integration, Integration, Payment APIs, Adyen Payments, Bluefin Payments, KillBill Framework, KillBill, PostgreSQL, Swagger
- Implemented and maintained RESTful web services with the HK2 framework for the company's core application, which is responsible for the lifecycle of subscriber accounts and tickets.
- Integrated several payment solution providers (Adyen, Bluefin, and Redsys) and developed payment plugins for the Kill Bill platform (Killbill.io).
- Created pipelines (including the Canary strategy) for mission-critical apps, using AWS EC2, AWS ECS, AWS CodeDeploy, and Amazon CloudFront for GitLab CI.
- Developed a full-stack application for customer management services using Vue and Java web services.
Senior Full-stack Developer | Architect2020 - 2021ASELSAN
Technologies: Java 8, React, Redux, Kubernetes, Red Hat OpenShift, Spring Boot, Hibernate, Liquibase, PostgreSQL, C4 Architecture Model, SCADA, Industrial Internet of Things (IIoT), DNP3, Modbus Protocol, IEC 62304, Elasticsearch, RabbitMQ, Domain-driven Design (DDD), Helm
- Developed a microservice-based application for a SCADA solution with a Spring Boot framework to provide back-end services.
- Built a front-end application for a SCADA solution with a React framework using Redux functions.
- Managed a Kubernetes and Red Hat OpenShift platform for the development and maintenance of the solution using predefined operators.
- Architected the microservice and a DDD (domain-driven design)-based distributed solution which provides a highly available-and-resilient service for the energy sector.
- Implemented IoT protocols like DNP3, Modbus, or IEC for the communication between SCADA system and RTU (remote terminal unit) devices.
- Developed and maintained a Helm chart for a robust and automated operational workflow.
Senior Back-end Developer2020 - 2020National Consumer Panel (via Toptal)
Technologies: Java, IBM WebSphere, Spring, Hibernate, Web Services, JAX-RS, GitLab
- Oversaw the development activities for the companies' web service applications which were built with Java using Spring and Hibernate frameworks.
- Maintained the application with bug fixes and configuration management for a GitLab codebase.
- Executed a database script for a data migration and development purposes using DBeaver.
- Deployed a package on a WebSphere 8 application server.
Senior Back-end Developer2020 - 2020CashCloud, Inc. (via Toptal)
Technologies: Microservices Architecture, AWS, Git, Web Services, Dropwizard, Amazon EC2 (Amazon Elastic Compute Cloud), AWS IAM, AWS Elastic Beanstalk, Amazon Web Services (AWS), Java
- Developed a RESTful integration on the Java Dropwizard project to connect with a new bank service.
- Created an admin endpoint to manage SSL certifications on the fly.
- Enhanced the company's AWS IAM usage to give people the correct permissions with their created roles.
Experienced Software Developer | Technical Team Leader2017 - 2020Turkish Airlines
Technologies: Microservices Architecture, log4j, Oracle WebLogic Application Server, Git, Agile Software Development, Web Services, Spring, Microservices, Dynatrace, IBM MQ, WebLogic, JUnit, Couchbase, Kubernetes, OpenShift, Hibernate, Spring Boot, Java
- Led the middleware web-services team of 12 engineers which implemented the comprehensive heap dump/thread dump analyses using MAT, Dynatrace, and Java Flight Recorder to detect memory leaks and class loader leaks.
- Oversaw a digital transformation project which involved converting a backbone monolithic web service application to microservices with the Spring Boot 2 framework and a migration from WebLogic to Redhat OpenShift.
- Enriched a CI/CD pipeline to increase operational quality by adding a binary build, Docker image creation, regression tests, and deployment to Redhat OpenShift with zero downtime.
- Created an in-house service virtualization tool for robust CI/CD pipelines. It was a Spring Boot project and supported HTTP, JDBC, and IBM MQ protocols.
- Built an abnormality detection system that analyzed error increase rates and detected abnormalities. We used the Spring Cloud Data Flow Kubernetes framework and combined RNN (recurrent neural network) and standard deviation for better performance.
Senior Back-end Developer2018 - 2019Freelance
Technologies: log4j, Git, Web Services, Spring, MySQL, Hibernate, Spring Boot, AWS Elastic Beanstalk, Amazon Web Services (AWS), Java
- Developed a set of microservices to provide RESTful ticket and reservation lifecycle methods with the Spring Boot framework and deployed on AWS EC2 and Elastic Beanstalk.
- Created high coverage unit tests to ensure code quality.
- Built a pipeline to create application binaries from a GitLab source and then deployed to AWS EC2 and Beanstalk environments.
Java Software Developer2013 - 2017Turkish Airlines
Technologies: Web Services, JAX-RS, JAX-WS, IBM MQ, WebLogic, JUnit, Hibernate, Spring Boot, Java
- Built a backbone middleware web-services project used by sales channels like website and mobile applications. The main integration was with a reservation system using IBM MQ 8. It was deployed to WebLogic 12c with a custom Jenkins deployer plugin.
- Composed enhanced unit tests for microservices with JUnit, REST Assured, Wiremock, and Spring Boot capabilities.
- Developed a front-end application with the JSF framework and Spring/Hibernate frameworks. The pages were used by analysts and business teams.
Software Quality Engineer2012 - 2013Turkcell
Technologies: SoapUI, JUnit, Java
- Carried out full lifecycle tests for Turkcell's billing rating charging mediation systems.
- Developed JUnit tests for billing and agency applications.
- Created quality reports for billing and agency applications.
Part-time Software Developer2010 - 2011Bosch and Siemens Home Appliances
- Developed ASP.NET pages for call center operations.
- Created and maintained SSRS (SQL Server Reporting Service) reports with complex SQL queries.
- Contributed to the development stages of .NET back-end components.