Selçuk Cihan, Software Developer in Istanbul, Turkey
Selçuk Cihan

Software Developer in Istanbul, Turkey

Member since June 9, 2018
Selcuk is a polyglot technologist with a focus on scalable backend services in the web ecosystem. As an ex-Amazonian, he crafts solutions by putting the customer first and ensuring operational excellence. Comfortable taking on work in any tech stack - though Serverless, Java, and Python have been a recurring theme in the past few years for him. Selcuk holds bachelor's and master's degrees in computer science.
Selçuk is now available for hire

Portfolio

  • Toptal client
    AWS, Serverless, Python, AngularJS
  • Amazon
    Java, Perl, AWS, Node.js, Linux, Spring, Agile, DevOps, PostgreSQL...
  • Intertech
    Microsoft .Net, C#, MSSQL, ElasticSearch, REST, Agile, Unit testing...

Experience

  • REST APIs, 5 years
  • JavaScript, 5 years
  • Java, 4 years
  • Python 3, 3 years
  • AWS DynamoDB, 3 years
  • Spring, 2 years
  • Perl, 2 years
  • AWS RDS, 2 years

Location

Istanbul, Turkey

Availability

Full-time

Preferred Environment

Node, React, Python, Unix, AWS, Serverless

The most amazing...

...project I've done is migrating from SQL to a managed NoSQL database without down time, involving three different services and over 20 different clients.

Employment

  • Software Developer

    2018 - 2019
    Toptal client
    • Created a public-facing web application with a serverless framework.
    • Created a serverless back end in Python on AWS Lambda and API Gateway.
    • Developed and maintained the front end, implemented with AngularJS.
    • Optimized cost resulting in more than 50% saving on the AWS bill.
    • Mentored developers and reviewed pull requests.
    • Improved performance by reengineering caching on CloudFront/S3.
    • Created serverless workflows using AWS Step Functions to integrate with external services.
    Technologies: AWS, Serverless, Python, AngularJS
  • Software Development Engineer

    2017 - 2018
    Amazon
    • 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
  • Senior Software Engineer

    2013 - 2017
    Intertech
    • 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 an award: https://www.bai.org/globalinnovations/awards/2017-winners/2017-internal-process-innovation-award.
    Technologies: Microsoft .Net, C#, MSSQL, ElasticSearch, REST, Agile, Unit testing, JavaScript, DevOps
  • Senior Software Engineer

    2011 - 2013
    Ziraat Teknoloji (formerly Fintek)
    • Designed and implemented workflow engine running on top of Oracle, serving over 100,000 workflow instances daily.
    Technologies: Microsoft .NET, C#, WinForms, WPF, Oracle
  • Software Engineer

    2010 - 2011
    AirTies Wireless Networks
    • 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
  • Software Engineer

    2009 - 2009
    CC Yazılım
    • 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

Experience

Skills

  • Languages

    JavaScript, Java, SQL, Python 3, Python 2, C#, Perl, C++, C
  • Libraries/APIs

    REST APIs, Node.js, React
  • Tools

    AWS CloudWatch, Amazon SQS, Amazon Cognito, AWS IAM, AWS CloudFormation, AWS Step Functions
  • Paradigms

    Unit Testing, DevOps, Agile, JAMstack
  • Platforms

    AWS EC2, AWS Kinesis, Linux, Docker, AWS Lambda
  • Storage

    AWS DynamoDB, AWS S3, NoSQL, AWS RDS, PostgreSQL, Oracle SQL, Microsoft SQL Server, Elasticsearch, MongoDB
  • Frameworks

    Django, Spring, Serverless Framework, AngularJS, Jest
  • Other

    AWS API Gateway, Tox, pytest

Education

  • Master's degree in Computer Engineering
    2008 - 2010
    Bogazici University - İstanbul, Turkey
  • Bachelor's degree in Computer Engineering
    2003 - 2008
    Bogazici University - İstanbul, Turkey
Certifications
  • AWS Certified Developer - Associate
    SEPTEMBER 2019 - SEPTEMBER 2022
    Amazon Web Services (AWS)
  • AWS Certified Solutions Architect - Associate
    SEPTEMBER 2019 - SEPTEMBER 2022
    Amazon Web Services (AWS)
  • AWS Certified Cloud Practitioner
    JUNE 2019 - JUNE 2022
    Amazon Web Services (AWS)

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