Selçuk Cihan

• Developed serverless web application on AWS.
• Created serverless workflows using AWS Step Functions to integrate with external services.
• Optimized cost resulting in more than 50% saving on AWS bill.
• Improved performance by reengineering caching on CloudFront/S3.
• Mentored developers and reviewed pull requests.

Technologies: Python, Serverless, Lambda, API Gateway, DynamoDB, Cognito, Datadog

• Developed and maintained the orchestration platform that processes Amazon’s catalog updates. The platform is able to handle tens of thousands of TPS, enabling the finest and largest catalog on earth. Uses Kinesis as the backbone and routes updates to the catalog to relevant downstream services.
• Added further functionality to a Node.js service which is a high TPS REST service for diff analysis.
• Refactored an orchestration engine which consumes Kinesis and calls downstream services such that the application can be started without any dependencies, thus enabling performance testing of the core.
• Supported the reconciliation engine (Java 8) that generates the retail catalog.
• Carried out live migrations of several web services without downtime. Successfully deprecated multiple legacy services in an effort to simplify the overall architecture and enable catalog growth.

Technologies: Java, Perl, AWS, Node.js, Linux, Spring, Agile, DevOps, PostgreSQL, ElasticSearch, JavaScript, Docker

• Supported the workflow engine (C#, Windows service) serving banking applications such as loans, customer complaints etc.
• Set up elastic to index workflow engine documents, enabling powerful search mechanisms for the end user.
• Designed and implemented a workforce management system that empowers the bank’s operation center. The application uses Microsoft’s solver foundation to solve the task assignment problem. This project got BAI global innovation award.

Technologies: Microsoft .Net, C#, MSSQL, ElasticSearch, REST, Agile, Unit testing, JavaScript, DevOps

• Designed and implemented workflow engine running on top of Oracle, serving over 100,000 workflow instances daily.
• Served as scrum master and mentored junior developers.

Technologies: Microsoft .NET, C#, WinForms, WPF, Oracle

• Implemented Teletext for the IPTV set-top box using C++.
• Developed a subtitle parser in C.
• Implemented a high-performance transport stream parser in C.

Technologies: C, C++, Busybox, Linux, RTSP, IPTV, Python, Perl, Teletext

• Designed and implemented a cross-platform desktop client in C++ utilizing wxWidgets GUI toolkit. The client database is SQLite.
• Designed and implemented the corresponding backup server in Java (J2SE). An application-level protocol is implemented for client-server communication, secured via SSL (OpenSSL). Stored files are encrypted (AES).
• Designed (visual design excluded) and implemented a web portal for serving online backup users. Users can download/browse backed up files through the portal. MySQL, Apache web server, and django framework are utilized.

Technologies: Java, C++, wxWidgets, Python, Django, wxPython, OpenSSL, MySQL, Apache web server, Django, SQLite