Developing TARS which is a high-frequency cryptocurrency trading system taking advantage of momentary price differences in crypto exchanges.

- TapPay: Host Card Emulation system for Yapi Kredi Bank, which allowed customers to use their Android smartphones to make contactless NFC payments. I implemented a backend system consisting of several modules (Spring Boot applications) that handle card digitization and tokenization, HSM integration, payment authorization and SDK lifecycle and more. For the client part, I developed an easy-to-use payment SDK that can be integrated to any Android banking application. The SDK and backend system supported MasterCard and Visa which are the most widely used schemes in Turkey. - Yapi Kredi Bank Mobile and World Mobile Apps: I implemented several screens, components for native Android and native iOS, and their backend developments using Spring MVC and Java. - MRZ Scanner Android SDK: To read ID cards and passports using Firebase ML Kit- React Native Libraries for Seal and Octopus security products: For banks developing hybrid applications.

- Yapı Kredi Investment World Web App: I developed several screens, main components and their backend developments using React and Spring. I also implemented several backend architecture related structures. - Yapı Kredi Internet Banking: I developed SOAP web services for other departments; several screens and their backend developments using jQuery and Spring. I migrated some old applications from Oracle Application Server(OC4J) to IBM WebSphere.

Developed: Google App Engine(Standard Environment) applicationsUsed: Python(2.7), JS(jQuery), Boostrap, PostgreSQL, Google NoSQL DB

Developed: A twitter auto-reply bot (@havabot) of the weather service www.iklim.coUsed: Python(2.7), Google NoSQL DB