Yasin is available for hire

Yasin Şahin

Verified Expert in Engineering

Software Developer

Ankara, Turkey

Toptal member since May 11, 2022

Expertise

Java Spring Boot Algorithms Database SQL Spring PostgreSQL Hibernate Data Mining C JavaScript MongoDB

Bio

Yasin is an engineer with 13 years of experience in the entire software development lifecycle, including architecting, estimating, leading, implementing, documenting, testing, and deploying scalable applications. He excels with Java technologies and enjoys working on blockchain and AI projects. He has managed teams developing products used by millions for large enterprise companies such as airlines and government. Previous roles have included R&D and software development director.

Portfolio

Medyasoft IT Group

Java, Java 8, Apache Kafka, Jira, Agile, Agile Transformation, Scrum

ePlatform (Medyasoft IT Group)

Algorithms, Java 8, PostgreSQL

ePlatform (Medyasoft IT Group)

Databases, Java 8, PostgreSQL, Jira

Experience

Computer Science - 15 years
Java - 13 years
REST - 10 years
Hibernate - 5 years
Spring - 5 years
Java 8 - 5 years
Spring Boot - 4 years
Spring Data JPA - 3 years

Availability

Part-time

Preferred Environment

Java 8, Spring, Spring Boot, Java

The most amazing...

...project I've delivered was for the revenue administration of one of the largest projects in the country and awarded for being the fastest-growing company.

Work Experience

Software and R&D Director

2021 - 2021

Medyasoft IT Group

Managed three IT groups with nine teams and 60+ engineers. Teams worked on projects for massive companies and products.
Contributed to a Bigforce product replicated to commercial databases to PostgreSQL near real-time. Implemented SQL Server to PostgreSQL replication by using CDC.
Oversaw project teams working on more than 20 projects for large enterprises such as Turkish Airlines, Turkcell Tech, Turkish Red Crescent, and Ministries.
Started the company's agile transformation. Different Agile approaches were applied to various teams such as Scrum and Kanban.

Technologies: Java, Java 8, Apache Kafka, Jira, Agile, Agile Transformation, Scrum

Software Development Director

2019 - 2021

ePlatform (Medyasoft IT Group)

Received the fastest growing IT company award in national IT 500 foundation.
Managed over 40 engineers who were working on different development and product teams.
Solved the performance issues of critical projects developed for the government and published publicly.

Technologies: Algorithms, Java 8, PostgreSQL

Lead Engineer

2018 - 2019

ePlatform (Medyasoft IT Group)

Managed multiple teams and organized SDLC for healthy growth by adding engineers to the project.
Set up a monitoring environment for live systems with JVM statistics and DB transactions.
Analyzed high-level functional requirements and converted them into architectural boundaries, and implemented critical modules such as user management.

Technologies: Databases, Java 8, PostgreSQL, Jira

Co-founder and Technical Lead

2013 - 2019

Ming Ltd.

Actualized a product idea with a government support program.
Developed an application and SaaS solution for lawyers and legal offices to make the daily routine of tracking cases simpler and easier.
Delivered an application end-to-end, from designing and developing phases to deployment and live support operations.

Technologies: Java 8, ZKoss, JavaScript, HTML5, Amazon EC2, Amazon S3 (AWS S3), Amazon RDS

Team Lead

2017 - 2018

ePlatform (Medyasoft IT Group)

Led to the development team for the Defter-Beyan System project of revenue administration in Turkey.
Analyzed technical and functional requirements to clarify necessities.
Designed system architecture used by millions with a 20,000+ TPS database load.

Technologies: Java 8, Spring, Spring Boot, React, PostgreSQL

Teaching and Research Assisstant

2009 - 2017

Hacettepe University

Gave tens of computer sciences courses to undergraduate students.
Consulted the hospital management of the university's medical faculty.
Researched P2P networks, anomaly detection in time series, and machine learning.

Technologies: Algorithms, Computer Science, Databases, Data Mining, Data Structures, C

Experience

Ledger Declaration System (Defter-Beyan Sistemi)

https://www.defterbeyan.gov.tr/tr

The Ledger Declaration System (DBS) is one of the government's most pivotal public projects. It meticulously manages the income and expenses of small taxpayers, generating highly sensitive and fault-tolerant financial declaration documents. The system serves over 3 million users, handles over 20,000 database transactions per second, and supports up to 50,000 concurrent users. I initially led the project as the team leader and was subsequently promoted to manager.

ISG-Katip

ISG-KATIP was a modernization and redevelopment project for the Ministry of Labor. This was a huge project developed for 35 million users. It keeps the tracks about occupational health and safety of all workers and companies in Turkey. The ISG-KATIP system consisted of a rule engine, scheduled task engine, and custom workflow engine. I was the technical lead of the project and solved most of the performance issues.

Bigforce

A data replication tool from commercial databases to PostgreSQL near real-time. It is based on the change data capture records of databases. It is also possible to migrate applications with databases with minimum downtime. I researched and designed the product's architecture.

SIYAP

An application for lawyers and law offices to make daily routines simpler and easier to track cases and executions with a SaaS solution. I implemented an OCR module with Tesseract and a file encryption module to protect highly critical records by managing keys for custom access management. The application ran on AWS, such as EC2, RDS, and S3. I delivered an application end-to-end, from designing and developing phases to deployment and live support operations.

Education

2013 - 2022

Near Completion of PhD in Computer Science

Hacettepe University - Ankara, Turkey

2009 - 2013

Master's Degree in Computer Science

Hacettepe University - Ankara, Turkey

2005 - 2009

Bachelor's Degree in Computer Science

Hacettepe University - Ankara, Turkey

Certifications

NOVEMBER 2019 - PRESENT

Academy of Leadership Certificate

Bogazici University

Skills

Libraries/APIs

React, JDBC, Spring REST, Java Servlets

Tools

Jira, RabbitMQ, Weka

Languages

Java, Java 8, SQL, C, JavaScript, HTML5

Frameworks

Spring Boot, Spring, Hibernate, ZKoss, JSON Web Tokens (JWT), ZK

Paradigms

REST, Agile, Scrum, Model View ViewModel (MVVM)

Storage

Databases, PostgreSQL, Spring Data JPA, MongoDB, Amazon S3 (AWS S3), Hazelcast, RDBMS

Platforms

Apache Kafka, Unix, Amazon EC2

Other

Computer Science, Algorithms, Data Structures, Operating Systems, Time Series Analysis, Data Mining, Leadership, Agile Transformation, Amazon RDS, Message Queues, Optical Character Recognition (OCR), P2P, Trusts, Machine Learning

Collaboration That Works

How to Work with Toptal

Toptal matches you directly with global industry experts from our network in hours—not weeks or months.

Share your needs

Discuss your requirements and refine your scope in a call with a Toptal domain expert.

Choose your talent

Get a short list of expertly matched talent within 24 hours to review, interview, and choose from.

Start your risk-free talent trial

Work with your chosen talent on a trial basis for up to two weeks. Pay only if you decide to hire them.

Top talent is in high demand.

Start hiring