I have been working as a freelance developer and accomplished the following activities:- crafted a high-performance Spreadsheet Engine with the full support of 450 well-known Spreadsheet functions in pure .NET (including modern functionalities like dynamic array formulas: SPILL feature)- crafted Number Format Library that 100% matches well-known Spreadsheet number formatting in .NET (C#)- improved performance and reached the best performance compared to the industry leaders (benchmarks made for comparison with best libraries)- crafted a lightweight, high-performance Javascript Engine (Interpreter) with pure .NET (C#). That is an open-source project: https://github.com/koculu/topaz- crafted a template engine similar to the Razor using Topaz Scripting Engine, that performs faster than ASP.NET Razor and delivers more flexibility for microservices architecture.- I have developed a web application using Dgraph database that delivers basic social network functionalities like following, sharing, messaging, and more. (Tech Stack: ASP.NET, Vue 3, C#, JavaScript, Dgraph, Redis, Docker)- I had the chance to help a few undergrad students with their Computer Science lessons and Homework- I work on a transactional and persistent LSM Tree written in .NET. https://github.com/koculu/ZoneTree

I have contributed to Aurea, USA through Crossover as a remote full-time contractor titled Chief Architect. Although, it was more like a full-stack Senior Developer Position with hands-on coding.Aurea's primary focus is modernizing live enterprise software.I had the chance to utilize and improve my C# (.NET), C++, and Javascript skills during my five years at Aurea.I have fixed 2000+ complex technical issues in various parts of the product that require an excellent understanding of the big codebase with different languages and business/customer requirements.I also utilized and improved my communication / technical leadership skills with the help of excellent colleagues from all around the world.In addition, I had the following responsibilities: - Detailed Code Reviews - Assure highest quality standards - Lead the release cycle of 16 different products - Enhance the Architecture Documents and Drawings - Manage / Refactor CICD pipeline - Dockerization - Moving legacy products to AWS Cloud. - Frontend - Backend - Database related development activities - Design and implementation of new features on top of existing products - Writing innovative tools to improve engineering teams to share information and enable newcomers to start development on day 1

I had the chance to participate development of MatrixIQ, leading financial trading platform's modern desktop application.My contribution was in the following areas:- Design and implement Special Spreadsheet Engine for Finance - Brought extensive .NET, WPF. experience- Implementation of a customizable and sophisticated user interface to display streaming Finance dataBetween 08.2015 and 10.2016 I continued my contributions part-time.

SmartMessage is a leading SMS and E-mail delivery company in Turkey. I have contributed in following areas:- implemented SmartMessage Excel integrated desktop application.- implemented customer support portal- utilized and improved my .NET, MVC, MVVM, MSSQL, ORACLE, Message Queue skills- made significant performance improvements on message delivery- fixed important bugs

Pagos, USA is a pioneer company that produces innovative Financial Products and Services. I have contributed to Pagos in following areas:- lead developer / architect of Pagos Spreadsheet Engine from version 4.1 to 5.1 during 5+ years- utilized and improved my C++, C# and Java skills- implemented XML parser and producer, Spreadsheet Chart Renderer, Spreadsheet Formula Parser- crafted Pivot Table engine (OLAP)- utilized and improved my multithreading programming skills- implemented hundreds of financial, mathematical and statistical functions- improved performance up to 25 times faster in execution and decreased memory usage to %20

I contributed as following:- crafted a mobile application framework, similar to Java SWT on desktop, using J2ME 2D graphics drawing API- developed a social-mobile application called Calcium- developed a mobile application Called Kanqa (both applications utilized the mobile framework)- contributed to J2EE server-side application

I contributed as following:- crafted a desktop application with Java SWT and OpenGL libraries- participated in the development to automate the manual keyword extraction from daily newspapers using OCR technology.- crafted Interpress Viewer application that is delivered monthly to the customers for their media tracking report

Part-time position focused on mobile games and applications with Java.