İlkay Aktaş, Developer in Ankara, Turkey
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İlkay Aktaş

Verified Expert  in Engineering

Java Back-end Developer

Ankara, Turkey
Toptal Member Since
June 9, 2022

İlkay has worked for over 14 years on the back end, mobile development, cloud projects, and supporting apps in production. As an AWS enthusiast, he has worked in the defense and finance domains. Additionally, İlkay has more than two years of experience managing an engineering team. He designed and developed many mobile and back-end applications and deployed them to the market.


Multitenancy, Auth0, Auth0 Management API v2, Java, React, Spring Boot...
Java, Kubernetes, Docker, Spring, Ansible, Vagrant, WebRTC, XMPP, Android, iOS
Microservices, Java, Spring, Apache Kafka, REST, WebRTC, Docker, Kubernetes...




Preferred Environment

IntelliJ IDEA, Visual Studio Code (VS Code), GitHub, GitLab, Postman, Jira, Bitbucket, Confluence, Slack

The most amazing...

...project I've worked on is a microservices architecture for a real-time communication platform that serves thousands of users.

Work Experience

Lead Software Engineer

2022 - 2022
  • Developed a platform that made companies log environment, social, and governance values to be tracked by investors.
  • Selected Chakra UI as a React library and implemented almost every screen using it.
  • Designed the back end as the hexagonal architecture and developed it in Spring Boot.
  • Configured all machines on AWS EC2 and deployed them to the cloud.
Technologies: Multitenancy, Auth0, Auth0 Management API v2, Java, React, Spring Boot, Amazon EC2

Team and Tech Lead

2021 - 2022
  • Designed a distributed server infrastructure that supported thousands of users.
  • Created Android and iOS applications, which run on a real satellite and 5G network.
  • Improved data transfer latency and packet drop on the satellite.
  • Succeeded in transferring a video over the satellite in less than 500 milliseconds (ms) latency and data or a message in less than 200 milliseconds (ms) latency.
Technologies: Java, Kubernetes, Docker, Spring, Ansible, Vagrant, WebRTC, XMPP, Android, iOS

Team and Technical Lead

2020 - 2022
  • Designed and developed near real-time messaging, data sharing, media streaming, video calls, and a conference platform as a technical lead.
  • Implemented an XMPP protocol to achieve text messaging and data transfer.
  • Implemented a WebRTC protocol to achieve video and voice streaming with a near real-time performance.
  • Added a map feature to track team members and detections on Google Maps, Esri Map, and Worldwind.
  • Prepared all on-premise infrastructure from scratch using Kubernetes, Vagrant boxes, and virtual environments.
  • Developed a CI/CD pipeline to deploy applications to on-premise infrastructure.
Technologies: Microservices, Java, Spring, Apache Kafka, REST, WebRTC, Docker, Kubernetes, Vagrant, Packer, Ansible, XMPP, CI/CD Pipelines, Jenkins, Clean Architecture, Android, Nexus, Esri, NASA WorldWind, Maps

Technical Software Leader

2021 - 2021
  • Developed a back-end software that injected all certificate fingerprints onto the Ethereum blockchain.
  • Created an Android application that retrieved fingerprints from the Etherium network during video calls over WebRTC.
  • Improved the weakness of WebRTC peer-to-peer communication using Ethereum smart contracts.
  • Added the secure video call feature to the Android application with WebRTC protocol.
Technologies: WebRTC, Java, Spring, Blockchain, Ethereum Smart Contracts, Amazon EC2, Android, Clean Code

Lead Software Engineer

2018 - 2021
  • Designed and developed an Android application that provided data sharing, text messaging, real-time voice communication using WebRTC, anomaly detection, and alarm management.
  • Designed a smart soldier system enriched with several sensors running on our custom Android operating system.
  • Designed the Android application in accordance with MVP and clean architecture.
  • Followed the reactive programming paradigm using RxJava.
  • Set a mesh network from soldiers to vehicles and headquarters.
  • Participated in all phases of this project, from the analysis to deployment.
Technologies: Java, Android, WebRTC, Session Initiation Protocol (SIP), IP Networks, Clean Architecture, Realm

Senior Software Engineer

2017 - 2018
  • Designed software that transformed monolith applications into microservices.
  • Designed the inter-service communication with REST API.
  • Developed a library for service registry and service discovery.
Technologies: Java, Spring, Hibernate, Microservices, Docker, MongoDB, Apache Camel, REST

Software Engineer

2009 - 2017
  • Worked as a team member on designing a near real-time, distributed, and data-centric C2 software used by the navy.
  • Developed track management and system management services using C++.
  • Integrated middle-range missiles for MBDA Italy and France and an underwater surveillance system integration for KDA Norway.
  • Participated in all phases of the software product lifecycle, from the offer, analysis, design, development, and testing to delivery.
Technologies: Java, C++, DDS, Hibernate, Swing, Linux, Red Hat Linux

Full-stack Developer

2008 - 2009
  • Developed a performance-based budgeting software for e-government platforms.
  • Developed the back end using Java, Apache iBATIS, JSP, Sybase, and MySQL.
  • Designed and developed the front end with the Ext JavaScript (Ext JS) framework.
Technologies: Java, JavaScript, Ext JS, Spring, Sybase, MySQL, Apache HTTP Server, Full-stack Development

Java Developer

2007 - 2007
University of Reading
  • Worked on a project managed by the civil engineering and management department of Reading University in the United Kingdom in collaboration with 11 universities worldwide.
  • Developed software that was a warehouse system for construction units. All construction units were followed by radio frequency identification (RFID) from the warehouse to the final building.
  • Participated in developing a Java-based MySQL module and an RFID Reading module.
Technologies: Java, Delphi, MySQL, RFID


This project was part of the master of science program. Sucre is a diabetes management platform that allows real-time data sharing and interactive communication between patients and doctors. I developed the front end in Android and the back end using Spring Boot. Also, I used the WebSocket APIs to provide instant data transfer between clients and servers.

Mobss KPSS Education Application

Mobss was a server-based Android application that allowed Turkish students to study for KPSS, a national exam, on their mobile devices. We designed and developed Android and iOS applications from scratch. We selected the Telerik platform as a cloud service that handled authentication, authorization, database, notification management, and email reminders. This was a startup attempt but, unfortunately, failed.

Annotation Processing to Generate Design Pattern Templates

This library generated builder pattern codes using the Java annotation processing feature. In those days, Lombok was not popular, and I should have found a solution to get rid of boilerplate codes in our projects.

Project Velodrome | Custom Mobile Architecture

After several years of experience in Android development, I decided to build a reference architecture application to have maintainable, reliable, readable applications in my future works. I envisaged this project as my base project and a start point for my next applications. The architecture was based on clean architecture rules, and the project structure is well organized. I enriched the project with activity templates. As a result, I use this project to produce and publish applications in less time than previously.

Quick Photo Filters

This is a Swift-based photo filtering application. As the product owner of the App Store, I designed, developed, and published this application from scratch. This application uses the Core Image framework and presents many preconfigured photo filters. Users are able to apply various filters to their photos in seconds.
2013 - 2018

Master's Degree in Medical Informatics

Middle East Technical University - Ankara, Turkey

2003 - 2008

Bachelor's Degree in Computer Science

Hacettepe University - Ankara, Turkey


REST APIs, RxJava, React, RxSwift, WebRTC, Auth0 Management API v2, Core Image, RxJava 2, ReactiveX


Docker Compose, Keycloak, AWS ELB, Amazon Cognito, Auth0, Vagrant, Ansible, Packer, Jenkins, AWS IAM, Amazon Simple Notification Service (Amazon SNS), IntelliJ IDEA, GitHub, GitLab, Postman, Jira, Bitbucket, Confluence, Slack, Amazon Virtual Private Cloud (VPC), Apache HTTP Server, Esri


Spring, iOS SDK, Spring Boot, Android SDK, Hibernate, Ext JS, Swing, Apache Camel


Java, C++11, Swift, JavaScript, C++, Delphi


Reactive Programming, Microservices, Agile Software Development, Unit Testing, Design Patterns, Service-oriented Architecture (SOA), Clean Architecture, Test-driven Development (TDD), DevOps, Object-oriented Design (OOD), REST, Clean Code


Amazon EC2, Docker, Android, Windows, Linux, Apache Kafka, Kubernetes, Nexus, Amazon Web Services (AWS), Visual Studio Code (VS Code), AWS Lambda, Red Hat Linux, Blockchain, iOS, Telerik


SQLite, Amazon S3 (AWS S3), Redis, PostgreSQL, MongoDB, Sybase, MySQL, Realm


Linux Shell Scripting, Aerospace & Defense, Android Architecture, Software Architecture, Solution Architecture, Amazon API Gateway, Hexagonal Architecture, Data Architecture, DDS, Medical Imaging, Full-stack Development, RFID, Session Initiation Protocol (SIP), IP Networks, XMPP, CI/CD Pipelines, Ethereum Smart Contracts, Multitenancy, Annotation Processors, NASA WorldWind, Maps

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