Ahmet Karakaya
Verified Expert in Engineering
Software Developer
Ahmet is a software engineering architect, team lead, and expert in communication technologies. He is skilled in Java, Python, Java Native Interface (JNI), Kafka, Cassandra, and Redis. Ahmet excels in finding solutions for the biggest problems in distributed systems, such as linear scalability, performance utilization, and concurrency.
Portfolio
Experience
Availability
Preferred Environment
Java, Spring Boot, Apache Kafka, Redis, Git, Agile Software Development, High-load, WebRTC, Python 3
The most amazing...
...project I've guided was the development of the BiP messaging application platform with 50 million users.
Work Experience
Senior Full-Stack Architect Developer
Yaacov Silberman
- Designed and Sip Platform and Proposed some alternative solutions.
- Investigated and proposed Sip/webrtc devices specific to kids.
- Having business discussions with the client, who is an entrepreneur.
Senior Full-stack Java Developer
MUFG Investor Services - Main
- Provided solutions for the investment industry on a global scale. They offer a range of services, from middle-office outsourcing to custody, fund administration, foreign exchange, and others.
- Developed features and fixed bugs for a finance web application tool. PrimeNG and Angular 12 are used. Built unit tests for each change, using Jasmine and Karma.
- Created features and fixed bugs on many Java 11 microservices. Developed unit and integration tests.
- Created and edited unit and IT test cases, fully complying with scenarios.
- Made new back-end functionalities and services. Also created a UI with Angular.
- Resynced an Angular project using its forked version. Created the Gitlab rebase branch from a forked repository, using the rebase branch as an upstream on the other project and managing a huge code propagation.
Back-end Developer
PhysIQ, Inc.
- Developed plugins and tools with Python and Kotlin on this platform.
- Created CI/CD pipelines on GitLab and created scripts.
- Performed load testing and analyzed the results with backend team. Found out improvement points and ensure the actual capacity.
Team Lead
Turkcell Technology
- Led the team at the design, implementation, and deployment phases to meet customer expectations for a secure and seamless video conferencing solution. It is a WebRTC-based solution.
- Assisted with program and project management, along with customer requirement analysis.
- Managed domestic and foreign team members working remotely, following agile development practices.
- Built a team with new hire interviews. Attended technical sessions to improve team talents.
- Investigated open-source solutions and prepared MVP products for demonstration purposes.
- Attended code review and technical discussion meetings to share experiences.
- Designed and implemented REST APIs to integrate with third parties, which had their own business logic and wanted to incorporate a video conferencing solution.
Team Lead
Turkcell Technology
- Managed the instant messaging platform VoIP and services development team in charge of value-added services, chatbots, location-based campaign services, payment features, sending money over the messaging application, and VoIP services.
- Led the team in the design, implementation, and deployment phases to meet customer expectations.
- Built a team with new hire interviews. Attended technical sessions to improve the team's technical expertise.
- Investigated Grafana metrics to find improvement sections for the modules in production. Shared updates with the team and organized and led technical discussions.
- Deployed media servers over AWS EC2 instances. Subscribers get a better experience by using the closest servers.
- Designed and implemented REST APIs to integrate with third parties that had their proper business logic and wanted to incorporate a messaging system.
Software Architect
Turkcell Technology
- Designed a highly scalable messaging application server.
- Migrated the project from the Oracle RDBMS to the Apache Cassandra NoSQL database.
- Coded and designed a push notification server for Apple and Android devices, handling approximately 100,000 TPS notifications.
- Delivered a solution for usual problems in distributed systems, such as linear scalability, performance utilization, and concurrency.
- Installed an OpenStack Object Storage server and programmed a client's access, attending a design intent meeting with the engineer from Red Hat.
- Selected the best technology stack to ensure the application would handle large amounts of traffic quickly and without issues.
Senior Software Developer
Turkcell Technology
- Developed a registration server for a messaging application, providing the new generation with instant messaging, voice, and video-call experience.
- Used custom, internally developed simulator tools and common ones such as JMeter for load testing.
- Monitored, analyzed, and tuned distributed memory usage.
Senior Software Developer
Nortel Netaş
- Developed A2, Nortel's VoIP solution implemented and currently maintained by foreign and Turkish engineers. It included over 40,000 Java classes and C codes.
- Handled the base architecture, including multithreading, JVM performance issues, traffic, and overload conditions.
- Collaborated with Genband's engineers, formerly Nortel, to implement new features and solve problems.
- Designed and developed telecommunications and enterprise projects using Java technologies.
- Developed a UDM project that is a device-change event dispatching system. Built an alarm management system for a secure XML gateway that provides web services from any endpoint and implemented a bulk SMS sender system for enterprise customers.
- Attended conference calls with product line management, design architects, technical support engineers, and managers to develop the best solutions for customers' needs.
Software Development Support
Nortel Netaş
- Collaborated with Nortel's customers, AT&T and T-Mobile.
- Identified and solved software, hardware, configuration, and signaling issues on GSM and UMTS systems.
- Prepared documentation with solutions to be used for similar issues.
Experience
Messaging Platform
https://bip.com/en/I worked on this project as a software developer, architect, and team lead.
Conference Solution
http://www.bipmeet.comThis product comprises many modules, including API interfaces and third-party solutions to manage meetings programmatically. Companies can use the same infrastructure with a private web address and specify user names on a screen. Third-party providers and individuals can view the meeting reports they participated in.
I also completed the payment system integration, allowing customers to buy a private meeting ID via credit card or mobile payment methods.
Mobile Device Management System
Bulk SMS Platform
Nortel VoIP Platform
http://netas.com.tr/I collaborated with Genband's engineers to implement new features and solve related problems while handling the base architecture, including multithreading, JVM performance issues, traffic, and overload conditions.
XML Gateway
I worked on this project as a software development phase leader.
Health Tourism System
Remote Patient Monitoring System
Automatic Prepaid Payment System
Push Notification Platform
• GCM and Firebase Cloud Messaging (FCM) XMPP Connection Server
• APNS TCP and HTTP/2 connection
• Java, Spring Boot, and Kafka
• Message throttling
• Parallel programming
• Grafana and Prometheus
BiP Web GUI
https://web.bip.comBiP Discover Management Console
https://discover.bip.comDatabase Migration Project
Reconciliation Application
I created new back-end functionalities and services.
I made back-end services implemented in terms of microservices concept.
ActiveMQ and Feignclient are used for intercommunication
The UI is created by Angular 12.
For identity services, Keycloak is used to create users and services with a range of roles.
Messaging App Similar to WhatsApp Business
https://api.ayoba.me/business/api-docs/FEATURES
• 3rd-parties can consume APIs.
• Security flows were designed to include JWT roles, HMAC, initial registration, etc.
• A linearly scalable platform handling high messaging throughput.
Education
Master's Degree in Computer Engineering
Marmara University - Istanbul, Turkey
Bachelor's Degree in Computer Engineering
Karadeniz Technical University - Trabzon, Turkey
Certifications
Artificial Intelligence A-Z 2024: Build 7 AI + LLM & ChatGPT
Udemy
Executive Briefing: Artificial Intelligence (AI) + ChatGPT
Udemy
To-Do App with Jetpack Compose MVVM - Android Development
Udemy
ChatGPT Complete Guide: Learn Midjourney, ChatGPT4 & More
Udemy
AWS Essentials
Udemy
Kotlin for Java Developers
Udemy
Mockito Next Level Java Unit Testing
Udemy
Junit 5
Udemy
Agile Software Development
Scrum.org
Professional Agile Leadership I
Koc University
Data Analyst Nanodegree
Udacity
Java Performance Tuning and Optimization
Oracle
Skills
Libraries/APIs
REST APIs, API Development, JDBC, Lombok, WebRTC, Node.js, Twilio API, JMS, GCM
Tools
IntelliJ IDEA, Git, Grafana, Kafka Streams, Jira, Bitbucket, Kong, Apache Tomcat, Postman, Apache Maven, GitLab CI/CD, GitLab, Gradle, Cucumber, GitHub, MQTT, Slack, Apache JMeter, Flink, NGINX, Jenkins, Firebase Cloud Messaging (FCM), Apache Avro, ChatGPT, Keycloak, ActiveMQ, Google Kubernetes Engine (GKE), Android Jetpack, Amazon Simple Queue Service (SQS), Amazon Simple Notification Service (Amazon SNS)
Frameworks
Spring Boot, Spring 4, Spring, Angular, JNI, Hibernate, JPA, OAuth 2, Spring Microservice, JavaScript MVC, Swagger, Ionic, Bootstrap, JUnit, Mockito, Akka, Spring 5
Languages
Java, SQL, C, Python, Kotlin, JavaScript, TypeScript, HTML, Python 3, Java 7, PHP, Gherkin, Scala, CSS
Paradigms
Agile Software Development, REST, Load Testing, Microservices, Object-oriented Programming (OOP), Serverless Architecture, Event-driven Architecture, Event-driven Programming, Back-end Architecture, Parallel Programming, Agile, Microservices Architecture, Test-driven Development (TDD), Unit Testing, Automated Testing, Continuous Integration (CI), Data Science, ETL
Platforms
JVM, Apache Kafka, Java EE, Linux, Docker, Amazon Web Services (AWS), AWS Lambda, Firebase, Oracle, Red Hat OpenShift, Apache Flink, OpenShift, Mobile, Twilio, Amazon EC2, Kubernetes, Google Cloud Platform (GCP), Android, Azure
Storage
Redis, Relational Databases, Redis Cache, MySQL, Cassandra, PostgreSQL, NoSQL, Databases, Amazon DynamoDB, Amazon Aurora, MongoDB, SQL Stored Procedures, Google Cloud
Industry Expertise
Telecommunications, Healthcare
Other
Software Development, Performance, Multithreading, VoIP, Leadership, APIs, Code Review, Message Queues, SOLID Principles, Back-end, Technical Leadership, Architecture, Communication, SOAP, Source Code Review, Technical Hiring, Interviewing, Integration, API Integration, CRM APIs, Software Design, Low Latency, Task Analysis, Software Architecture, WebLogic, Back-end Development, HTTP REST, Messaging, Live Chat, API Platforms, Java Native Interface (JNI), Distributed Systems, SIP, Coherence, SMS, Pull Requests, Scripting, Full-stack, Team Leadership, Containerization, WebSockets, Data Processing, SSL, Amazon RDS, API Gateways, Multitenancy, Containers, CTO, Session Initiation Protocol (SIP), Full-stack Development, Cryptography, Scrum Master, Video Calling, Stream Processing, OpenStack Swift, Payment APIs, IPsec, IDS/IPS, High-load, CI/CD Pipelines, Predictive Modeling, Data Wrangling, Probability Theory, Chatbots, Open Source, Statistics, Web Scraping, HTTP, APNs, Prometheus, XMPP, Single Sign-on (SSO), Finance, OpenAI, Artificial Intelligence (AI), Lambda Functions, Serverless, Data Engineering, Peer-to-peer Networking, VoIP Administration
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