Ramazan is available for hire

Ramazan Yıldız

Verified Expert in Engineering

Full-stack Developer

Istanbul, Turkey

Toptal member since January 20, 2020

Expertise

Full-stack Integration Front-end Back-end Developers UI Development Web Development API System Security Cloud Engineering AWS SaaS AWS RDS PWA Auth0 CouchDB Apache Cordova Ionic Vaadin AWS DevOps

Bio

Ramazan is a full-stack developer, architect, and DevOps Engineer with 16+ years of software development experience and a Master of Science degree in computer engineering. He is proficient in various business applications and has proven expertise with Node.js, Python, Java, Angular, React, and AWS technologies.

Portfolio

Coino.com

Java 21, Virtual Threads, Node.js, Knex.js, Go, SQLite, React, Ionic 7...

Siemens

Algorithms, Amazon API Gateway, Amazon CloudFront CDN, Amazon Cognito...

Siemens

Auth0, Java, Amazon Cognito, Keycloak, Cloud, Cloud Platforms, OAuth 2

Experience

Full-stack - 16 years
Web Development - 10 years
Angular - 9 years
Node.js - 6 years
Java 8 - 5 years
Mobile App Development - 4 years
Ionic 3 - 4 years
AWS DevOps - 3 years

Availability

Part-time

Preferred Environment

Amazon Web Services (AWS), Angular, Java, Git, Node.js, React, Python, AWS Cloud Development Kit (CDK), Terraform, Ionic

The most amazing...

...project I've developed is an order book management system for a crypto exchange platform.

Work Experience

Full-stack Developer & Architect

2023 - 2024

Coino.com

Built an order book management system (OBMS) from scratch for a crypto exchange platform in collaboration with a talented colleague. The OBMS allows multi-session integration between an integral liquidity provider (LP) and the exchange platform.
Enabled the OBMS to provide near real-time processing performance, simultaneously handling 200 trading pairs on a regular server with a 3-4 millisecond processing speed and 300 trading pairs in 8-10 milliseconds.
Created a Grafana metrics dashboard for the OBMS. Integrated Telegram for the alerts and a Watchdog engine that constantly audits the exchange for expired and stuck open orders, resolving issues where necessary.
Configured and created bots in the OBMS to perform buy-and-sell operations executing the given algorithms.
Handled significant reports and modules such as price depth configuration, hedging, bot operations, exchange trading pairs, LP symbols and prices, tickers, the health dashboard, exchange account and user management, and LP session management.
Developed a separate service for performance measurement with TestBench to simulate mock LP and exchange. It produces market data traffic against the OBMS and captures the output.
Profiled, measured, and improved the OBMS processing speed under the traffic.
Used a cutting-edge tech stack and cost-effective architectural design for the OBMS, which includes Java 21 with virtual threads, Helidon, Node.js with Knex.js, Go, SQLite, NATS, React with Ionic, Terraform, GitHub Actions, Amazon ECR, and QuickFIX.

Technologies: Java 21, Virtual Threads, Node.js, Knex.js, Go, SQLite, React, Ionic 7, Progressive Web Applications (PWAs), NATS, Docker Compose, Infrastructure as Code (IaC), Terraform, GitHub Actions, Telegram Messenger API, Grafana, Prometheus, Algorithms, Helidon, QuickFIX, Amazon Elastic Container Registry (ECR), Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Tailwind CSS, API Integration, Back-end, Agile, Scrum, Architecture, Jest, Express.js, Responsive Web Design (RWD), JPA, PWA, Databases, JavaScript MVC, SSL Certificates, Vite, GitHub, Authentication, Authorization, Front-end Development, CSV, Data Visualization, Amazon CloudWatch, Amazon Elastic Container Service (ECS), WebSockets, API Design, SCSS, Capacitor, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Database Structure, Agile Software Development, OpenAI API, Functional Programming, AWS CLI, TypeScript 3, IntelliJ IDEA, REST, Mobile Development, AWS Certificate Manager, Cloud, Cloud Platforms

Full-stack Developer & Architect

2023 - 2024

Siemens

Designed and developed Wheretobuy product, a B2B partner and client portal, and mainly worked on the back-end and cloud services. Wheretobuy periodically scans the Siemens product portfolio for each country or region: Brazil, Malaysia, and Turkey.
Created and developed sftp.wheretobuy.com, an SFTP service that enables partners to integrate their stocks into Wheretobuy. These integrated partner stock shares are then published and served publicly to their clients.
Built Wheretobuy's admin portal while a colleague created its public-facing front end. The portal features a manual Excel stock share module that I developed, so partners can manually share stocks by uploading Excel sheets or copy-pasting raw data.

Technologies: Algorithms, Amazon API Gateway, Amazon CloudFront CDN, Amazon Cognito, Amazon Cognito User Pools, Amazon EC2, Amazon Route 53, Amazon S3 (AWS S3), GitLab CI/CD, Spring Boot, Java, AWS Transfer Family, SFTP, ETL, Angular, Amazon, MySQL, Spring Data JPA, Front-end Architecture, APIs, Front-end Design, AWS SDK, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Express.js, Responsive Web Design (RWD), JPA, Databases, JavaScript MVC, Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Vite, Authentication, Single Sign-on (SSO), Authorization, Microsoft Entra, iOS, Google Maps API, Front-end Development, CSV File Processing, CSV, Data Visualization, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, Database Structure, Agile Software Development, OAuth, Amazon EKS, AWS CLI, TypeScript 3, IntelliJ IDEA, REST, AWS Certificate Manager, Serverless, Cloud, Cloud Platforms, OAuth 2

Full-stack Developer and Software Architect

2022 - 2024

Siemens

Developed a custom Auth0 service for streamlined user management and access control for multiple IT applications. It handles user registration, authentication, and token generation and includes organization-specific and user-specific claims.
Implemented role-based access control to manage user permissions within each application. Users can belong to multiple applications with varying roles, ensuring granular control over access to resources.
Implemented organization-based access control to restrict access to specific applications based on user affiliation. The service generates access tokens with organization-specific claims to enforce fine-grained authorization.
Implemented authentication and authorization layers using different token vending machines such as Keycloak, AWS Cognito, and Auth0.

Technologies: Auth0, Java, Amazon Cognito, Keycloak, Cloud, Cloud Platforms, OAuth 2

Tech Lead & Ionic Mobile Developer

2023 - 2023

Prudential

Designed new modules for the TellMe app based on company business unit requirements. Prudential Asia's HR unit is the product owner of this app, where company employees give feedback to each other.
Handled DevSecOps scan reports using Nexus OSS, Aqua Security, dynamic application security testing with Burp Suite, and static application security testing with Fortify. Managed meetings between IT experts, DevSecOps experts, and customer groups.
Managed user acceptance tests. Early life support is given during product launch.

Technologies: Ionic, Angular, Cordova, DevSecOps, Azure, Spring Boot, Microsoft Intune, SFTP, Workday, User Acceptance Testing (UAT), Bitbucket, Jenkins, Jenkins Pipeline, Azure Kubernetes Service (AKS), Front-end Architecture, Figma, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), User Experience (UX), JPA, PWA, Databases, JavaScript MVC, Kubernetes, Amazon RDS, Authentication, Single Sign-on (SSO), Authorization, Android, iOS, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Technical Leadership, Database Structure, Agile Software Development, OAuth, Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Mobile Development, Cloud, Cloud Platforms

Ionic Mobile Developer

2022 - 2023

Prudential

Created Workday and SFTP integration. Implemented SSO authentication.
Enhanced existing product functionalities and created new modules.
Supported the user acceptance tests, collected new requirements from the company business units, and further covered these requirements.

Technologies: Ionic, User Acceptance Testing (UAT), Angular, Cordova, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), User Experience (UX), JPA, PWA, Databases, Kubernetes, Amazon RDS, Authentication, Authorization, Android, iOS, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Database Structure, Agile Software Development, OAuth, Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Mobile Development, Cloud, Cloud Platforms

Full-stack Java Developer

2021 - 2023

MUFG Investor Services

Developed features using PrimeNG and Angular 14 for a finance web application portal. Fixed bugs, built unit tests for each change using Jasmine and Karma, and created complex web pages.
Created features on multiple Java 11 and Spring Boot microservices. Fixed bugs, developed unit and integration tests, and actively reviewed Java code from teammates.
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.
Contributed to migrating and reimplementing the old Flash-based products' front and back-end parts, which includes multitenancy, as new single-page web applications and Java Spring Boot-based modern microservices.

Technologies: Java, Spring Boot, Apache Maven, GitLab, Microservices, SSL, Production Support, Angular, Jenkins, Oracle, Amazon Web Services (AWS), MongoDB, Spring Data MongoDB, ActiveMQ, Spring Data JPA, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, API Integration, Back-end, Agile, Scrum, Architecture, Responsive Web Design (RWD), JPA, Databases, JavaScript MVC, Datadog, Amazon RDS, Authentication, Authorization, Front-end Development, CSV File Processing, Amazon CloudWatch, Java Message Service (JMS), HTML5, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Database Structure, Agile Software Development, OpenAI API, AWS CLI, Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Microservices Architecture, Cloud, Cloud Platforms

Ionic Mobile Developer

2022 - 2022

Prudential

Redesigned and developed the TellMe app, an internal application used by employees to provide feedback to each other.
Developed web and mobile applications. Released and published the iOS and Android apps via the Microsoft Intune server. Deployed the web app in the Azure Kubernetes Service environment via Jenkins CI/CD automation and created Jenkins CI/CD scripts.
Contributed to the back-end implementation, developed Java services, and designed front and back-end architecture.
Documented the product and prepared high-level design documents.

Technologies: Ionic, Angular, Cordova, Java, Spring Boot, DevSecOps, Vulnerability Assessment, Jenkins, Azure, Mobile App Development, Web App Development, SFTP Integration, Front-end Architecture, Figma, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), User Experience (UX), JPA, PWA, Databases, JavaScript MVC, Kubernetes, Amazon RDS, Authentication, Authorization, Android, iOS, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Database Structure, Agile Software Development, Angular CLI, TypeScript 3, IntelliJ IDEA, REST, Mobile Development, Cloud, Cloud Platforms

Full-stack Developer & Architect

2021 - 2022

Siemens

Engaged in a team to design and develop digionenow.com, a B2B partner and client portal with modules like product and stock search, campaigns, partner finder, and training. It's rolled out in Turkey, Brazil, and Malaysia.
Designed the virtual private cloud (VPC) environment. The product is public-facing, but its back-end services rely on a strictly private Amazon VPC access to the company intranet for SAP-related on-prem services.
Implemented the product's back-end services using Java Spring Boot, Node.js, and Python.

Technologies: Amazon API Gateway, Amazon, Amazon CloudFront CDN, Amazon Cognito, Amazon Cognito User Pools, Algorithms, Amazon DynamoDB, Amazon EC2, Amazon Route 53, Amazon S3 (AWS S3), Amazon Simple Email Service (SES), AWS Transfer Family, Amazon Virtual Private Cloud (VPC), Angular Bootstrap, SFTP, MySQL, AWS VPN, Spring Boot, Node.js, Serverless Architecture, Python 3, Spring Data JPA, Front-end Architecture, APIs, Front-end Design, AWS SDK, Amazon Simple Queue Service (SQS), Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, PWA, Databases, JavaScript MVC, Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Authentication, Single Sign-on (SSO), Authorization, Android, Google Maps API, Front-end Development, Chart.js, CSV, Data Visualization, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, Database Structure, Agile Software Development, OAuth, Amazon EKS, Zuul, AWS CLI, Angular CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Microservices Architecture, Cloud, Cloud Platforms, Multi-factor Authentication (MFA), OAuth 2

Full-stack Angular & Node.js Developer

2021 - 2022

Cleardoc Inc. (dba OPENREEL)

Implemented back-end features to the remote video creation product, creating REST and Socket.io APIs with NestJS and Socket.io, MySQL with Node.js and Sequelize, and video transcoding APIs with Redis and Bull.
Worked on the web-based remote video capture product—a conferencing platform where participants join and capture 4K video remotely. Several scenarios are implemented for browser-based, end-to-end testing using Cypress.io and Puppeteer.
Developed UI features using Angular 12 and fxFlex layouts.

Technologies: Angular, Node.js, Socket.IO, Sequelize, NestJS, Redis, MySQL, Amazon Web Services (AWS), Cypress, Puppeteer, NgRx/store, Full-stack, Web Development, Java 8, SQL, TypeScript, Test-driven Development (TDD), Front-end, Videos, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, Twilio, API Integration, Back-end, Agile, Scrum, Architecture, Express.js, Video Processing, Responsive Web Design (RWD), JPA, Google Cloud Platform (GCP), Databases, JavaScript MVC, Sentry, Amazon RDS, GitHub, Authentication, Single Sign-on (SSO), Authorization, Front-end Development, CSV, Amazon CloudWatch, HTML5, API Design, Video Streaming, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Redis Cache, Database Structure, Agile Software Development, AWS CLI, Angular CLI, Angular Material, IntelliJ IDEA, REST, Microservices Architecture, Cloud, Cloud Platforms

Angular Front-end Developer

2020 - 2022

GPSENGINE

Redesigned the PHP-based old portal as a new responsive Angular portal.
Displayed vehicles and animated vehicle movement histories using Google Maps.
Used an Apollo client for consuming GraphQL-based APIs.

Technologies: Angular, Apollo, GraphQL, Google Maps, RxJS, TypeScript, Web Development, Front-end, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, CI/CD Pipelines, JavaScript, API Integration, Back-end, Agile, Scrum, Architecture, Responsive Web Design (RWD), JavaScript MVC, GitHub, Authentication, Authorization, Google Maps API, Front-end Development, CSV, Data Visualization, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Angular CLI, IntelliJ IDEA, REST, Microservices Architecture

Full-stack Angular & Java Developer

2021 - 2021

E4 Logics

Developed an Angular project with a PrimeNG Poseidon theme and Angular 11, creating several complex pages following a responsive design. Used Jasmin and Karma for unit testing.
Built back-end services with Spring Boot and Java 11. Financial data is processed with PostgreSQL, and Postman is used for end-to-end testing.
Created a CI/CD pipeline and a quality system for testing. Angular and back-end services are deployed to AWS.

Technologies: PrimeNG, Material Design, Java 11, Spring Boot, PostgreSQL, Amazon S3 (AWS S3), Full-stack, Web Development, Java 8, Angular, SQL, TypeScript, Front-end, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, JavaScript, Back-end, Agile, Scrum, Responsive Web Design (RWD), JPA, Databases, JavaScript MVC, Amazon RDS, SSL Certificates, Authentication, Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Database Structure, Agile Software Development, AWS CLI, Angular CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms

Java Expert

2020 - 2020

Ride2go.com (owned by Fahrgemeinschaft.de GmbH)

Contributed to developing the ride2go.com ridesharing platform, a progressive web app with Ionic and Angular. I embedded it into different portals and implemented several features and bug fixes during my 10-month engagement.
Used GitHub for issue tracking and preparing pull requests.
Embedded ride2go.com responsively in several portals using iFrame.

Technologies: Ionic 3, Angular, React, Gatsby, Spring Boot, Docker, Mobile App Development, Java 8, TypeScript, Front-end, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, JavaScript, API Integration, Back-end, Agile, Scrum, SDKs, Responsive Web Design (RWD), JPA, PWA, Databases, JavaScript MVC, GitHub, Authentication, Authorization, Front-end Development, HTML5, API Design, SCSS, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Database Structure, Agile Software Development, OpenAI API, Angular CLI, IntelliJ IDEA, REST, Mobile Development

Full-stack Software Developer and Architect

2019 - 2019

Pinsoft

Contributed to the development of a middleware integration software and implementation of a layer on top of a legacy telnet speaking airline ticketing system and this layer is finally opened as a modern Rest API. It handled flight booking, canceling, querying with pagination using telnet protocol; then mapping this telnet data with GSON library into Java POJO objects; and finally serving data as Rest services.
Designed and developed the management web site for flight disruptions of an airline company. This web application is used in the customers' intranet to automatically handle reservations (PNRs) of disrupted flights or manually handle these PNRs with the aid of SVG graphics. The site was developed in collaboration with a colleague of mine. The disruption solution algorithm was developed by another team. Mock rest services were created as integration points using Angular-in-memory-web-API. Swagger API is documented for the back-end team.

Technologies: Snap.svg, Swagger, Bootstrap, Angular, GSON, Telnet Protocol, RESTful Services, Spring Boot, Full-stack, Java 8, SQL, REST APIs, JSON REST APIs, CSS, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, JavaScript, Back-end, Agile, Scrum, Architecture, Databases, Front-end Development, API Design, Thymeleaf, Back-end Development, System Architecture, Angular Material, IntelliJ IDEA, REST

Full-stack Software Developer and AWS Architect

2018 - 2019

SIEMENS AG

Architected, designed, and developed www.siemensdigipartner.com, www.russiadigipartner.com, Siemens Partner Web Portal, and Siemens DiGi Partner iOS and Android mobile apps from scratch. This portal and its mobile apps are designed for partners of Siemens and for customers of the targetted Siemens partners. The site was initially developed for Siemens Turkey then rolled out for Russia, Italy, and Brazil. The project has several modules for logged in users such as user and partner management, SAP stock query, stock share, partner performance dashboard, orders and logistics tracking, product price list, project special price request, sales campaigns, trainings, online support, marketing videos, shopping catalog, news feed, survey, email, and mobile push notifications. The development team consisted of one architect (me), two senior software developers, and one SAP expert.

Technologies: SAP, VPN, Amazon Virtual Private Cloud (VPC), Amazon EC2, Load Balancers, AWS Lambda, Amazon Cognito, Amazon Cognito User Pools, API Gateways, Amazon Route 53, Amazon CloudFront CDN, Amazon S3 (AWS S3), Amazon Web Services (AWS), MySQL, Spring Boot, Ionic 3, Bootstrap, Angular, Full-stack, Amazon API Gateway, Java 8, SQL, Cordova, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Amazon Simple Queue Service (SQS), Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Google Cloud Platform (GCP), PWA, Databases, Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Web Scraping, Authentication, Single Sign-on (SSO), Authorization, Android, iOS, Google Maps API, Front-end Development, CSV, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Order Management, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, Database Structure, Agile Software Development, OAuth, Apple Push Notifications, Zuul, AWS CLI, Angular CLI, IntelliJ IDEA, REST, Mobile Development, AWS Certificate Manager, Serverless, Cloud, Multi-factor Authentication (MFA)

Full-stack Software Developer and Architect

2018 - 2018

SIEMENS AG

Implemented the Boto 3 Cognito Identity Provider flows with Python for runtime interaction with Cognito.
Deployed as AWS Lambda functions with serverless architecture.
Implemented also AWS Lambda custom authentication and authorization functions with Python for AWS API GW based web and mobile applications.

Technologies: AWS Lambda, API Gateways, Python, Amazon Cognito, Boto 3, Amazon Cognito User Pools, Full-stack, Mobile App Development, Amazon API Gateway, Amazon Route 53, Java 8, SQL, Production Support, Spring Boot, Cordova, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Amazon Simple Queue Service (SQS), Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Scrum, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Google Cloud Platform (GCP), Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Authentication, Single Sign-on (SSO), Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, Zuul, AWS CLI, Angular CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms, Multi-factor Authentication (MFA)

Software Architect

2018 - 2018

SIEMENS AG

Installed and configured a Docker-based Gitlab Runner instance on an Ubuntu AWS EC2 server which is located in a private AWS VPC subnet. Then registered this runner to the corporate GitLab Server via Secure VPN tunnel only.
Automated CI/CD pipeline for AWS Based applications (Java, Angular Web) of Siemens Turkey IT. Also automated legacy intranet Tomcat applications with this CI/CD pipeline using Cargo deployments. I designed and developed the entire process on my own.

Technologies: Docker, Continuous Delivery (CD), Continuous Integration (CI), GitLab, Git, Full-stack, Mobile App Development, Amazon Route 53, Web Development, Java 8, Oracle, SQL, SSL, Jenkins, Spring Boot, Cordova, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, API Integration, Back-end, Agile, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Databases, Amazon Simple Notification Service (SNS), Amazon RDS, SSL Certificates, Authentication, Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Back-end Development, System Architecture, User Interface (UI), Software Architecture, Auth0, Auth0 API, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, Zuul, AWS CLI, Angular CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms

Full-stack Software Developer and Architect

2017 - 2018

kariyerlianne.com

Architected, designed, and developed the www.kariyerlianne.com web site on AWS from scratch. The goal of this site was to help mothers with professional careers to find part-time, freelance, periodic, or project-based job opportunities that allow mothers to stay in business life while continuing to care for their children.

Technologies: MySQL, GitLab CI/CD, Amazon Web Services (AWS), Node.js, Bootstrap, Angular, Full-stack, Amazon API Gateway, Amazon Route 53, Web Development, Java 8, AWS DevOps, TypeScript, Mobile, REST APIs, JSON REST APIs, HTML, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, Architecture, Team Leadership, Express.js, Responsive Web Design (RWD), Databases, Amazon RDS, SSL Certificates, Authentication, Authorization, Front-end Development, Amazon CloudWatch, HTML5, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Database Structure, Agile Software Development, AWS CLI, Angular CLI, Angular Material, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms

AWS DevOps Architect

2017 - 2018

SIEMENS AG

Created an AWS VPN tunnel connected to the Siemens intranet in collaboration with global Siemens cloud team. Attached this VPN connection, and created an AWS VPC environment having four subnets with required resources; three of these subnets were private—routed only to the VPN gateway, and their resources were reachable from Siemens intranet and 1 is public-facing having a bastion host, internet gateway, and NAT gateway. This VPC was used for running Siemens Turkey IT applications. Mobile and web applications were developed based on this environment. And ongoing legacy intranet web applications (Tomcat web apps) and Oracle DB were migrated to this environment. The target was to reduce the running cost of IT applications to 10%.

Technologies: Amazon Virtual Private Cloud (VPC), VPN, Amazon Web Services (AWS), Full-stack, Amazon API Gateway, Amazon Route 53, AWS DevOps, REST APIs, JSON REST APIs, Spring Data JPA, Front-end Architecture, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, SaaS, Back-end, Agile, Architecture, Team Leadership, Databases, Amazon RDS, SSL Certificates, Front-end Development, API Design, Back-end Development, User Interface (UI), Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Agile Software Development, OAuth, AWS CLI, IntelliJ IDEA, REST, AWS Certificate Manager, Cloud, Cloud Platforms

Full-stack Software Developer and Architect

2016 - 2018

SIEMENS AG

Designed and developed the Siemens Pocket mobile app and its back-end services. Ported Siemens TR intranet IT web applications as mobile apps inside this single Siemens Pocket mobile application.
Implemented the Annual Leave Request app where employees can see their remaining annual leave day balances, request a new annual leave request, and more.
Implemented the Business Approvals App where employees can see all their pending approvals raising from the different processes within the company. This app is a dashboard for all pending approvals of any employee.
Implemented the Lead Together mobile app for site technicians; when they are at a customer's for maintenance or service, they can negotiate with the customer and catch new maintenance, service, or project opportunities.
Implemented the Technician Intervention mobile app. Onsite maintenance operations are logged (expanses, hours, operations, pictures, and more) via this application and signed by the customer. PDF reports are generated and delivered via mail.
Implemented the 3i app. Employees have the possibility to suggest improvement ideas; upon measurable income, the idea owner earns money. With this process, high income has been obtained in the company.
Implemented the Shuttle Search app. Company shuttles, their destinations, and chauffeur contact info can be looked up.
Implemented the Meal Menu of the Day app, the most frequently used app within the company.
Implemented the Training Evaluation app. Corporate on-site training was evaluated with this app, saving paper and digitizing employee feedback.

Technologies: MySQL, Oracle Database, Spring Boot, Angular, Ionic, Full-stack, Mobile App Development, Amazon Route 53, Java 8, Oracle, SQL, Cordova, TypeScript, REST APIs, JSON REST APIs, Spring Data JPA, APIs, Front-end Design, AWS SDK, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, Architecture, Team Leadership, Responsive Web Design (RWD), JPA, Databases, Amazon RDS, SSL Certificates, Authorization, Android, iOS, Front-end Development, Product Engineering, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Software Architecture, Order Management, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, Database Structure, Agile Software Development, OAuth, Angular CLI, IntelliJ IDEA, REST, Cloud

Full-stack Software Developer and Product Manager

2015 - 2018

SIEMENS AG

Architected, designed, implemented, and managed the whole PDR process, the project execution system, and a web application for financial execution of ongoing projects of energy divisions in Siemens. More than 120 projects are managed on this system.
Completely designed and coded the PDR product. The PDR is highly complex in terms of business logic, consisting of around 120,000 lines of Java code churn. I also developed SAP interfaces and Excel data upload-export interfaces.
Acted as a product owner, organizing several meetings with in-company customers, defining the product roadmap, and executing the development.

Technologies: Oracle Database, Apache Tomcat, Hibernate, Spring, Vaadin, Full-stack, Java 8, Oracle, SQL, REST APIs, JSON REST APIs, Spring Data JPA, APIs, Full-stack Development, JavaScript, Back-end, Agile, Responsive Web Design (RWD), JPA, Databases, Amazon RDS, SSL Certificates, Front-end Development, Product Engineering, API Design, Back-end Development, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, IntelliJ IDEA, REST, Cloud

Full-stack Software Developer

2017 - 2017

SIEMENS AG

Implemented the Purchase Order Survey web application and mobile responsive Vaadin application. The app is used by supply chain management (SCM) of Siemens Turkey. Survey questions with categories are prepared on this system and addressed to the SCM users for evaluation. The system has an SAP interface (SAP JCO) and SCM portal interface; surveys are manually prepared, automatically triggered by events from SAP system or SCM portal then sent via mail.
Implemented the ESP, Employee Search Page web application. ESP provides an employee search facility. Employee records on this page are linked to an LDAP database search page of Siemens Global as well which is useful to see further details of an employee. All Siemens employees are allowed to access this page. The application consists of a single web page including search criteria area, lazy loading listing table, and pagination widgets.

Technologies: Oracle Database, Spring Data, Spring Boot, Vaadin, Full-stack, Java 8, REST APIs, JSON REST APIs, Spring Data JPA, APIs, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Agile, JPA, Databases, Amazon RDS, SSL Certificates, Front-end Development, Product Engineering, API Design, Back-end Development, User Interface (UI), Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Database Structure, Agile Software Development, OAuth, IntelliJ IDEA, REST, Cloud

Full-stack Software Developer and Architect

2017 - 2017

SIEMENS AG

Implemented the Siemens Turkey mobile app designed for partners of Siemens Turkey. For the admin area, a responsive web application was developed with Angular 4 and Angular Material Design components. Apache CouchDB NoSQL and Offline PouchDB JavaScript Database were used. CouchDB provided great Rest interfaces and delivered change notifications making the application very interesting.

Technologies: Ionic, Angular, Google Maps, JavaScript, PouchDB, NoSQL, CouchDB, Spring Boot, REST APIs, JSON REST APIs, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, SaaS, Back-end, Architecture, JPA, Databases, Amazon RDS, SSL Certificates, iOS, Front-end Development, Product Engineering, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Solution Architecture, Content Delivery Networks (CDN), Database Structure, OAuth, Angular Material, IntelliJ IDEA, REST, Cloud

Full-stack Software Developer and Architect

2016 - 2016

SIEMENS AG

Implemented the Oracle SCD Downloader app. This is a VB.Net middleware service developed for Siemens AG Österreich - Transformers Factory in Weiz city. The app connects to Oracle Database over ODP.NET (Oracle Data Provider for .NET), reads all of the employee data from an Oracle view, and stores it in a staging table on the SQL server. It then reads a subset of records from the staging table and updates/inserts these records into the target table on the same schema on SQL Server. The strength of this application is that no Oracle-specific client is needed to be installed in the release platform which is undesired and painful. This application is portable itself and uses Oracle Managed Data Access Client included in the release package which is sufficient for connecting to the Oracle at runtime.

Technologies: Microsoft SQL Server, Oracle 12c, ODP.NET, VB.NET, Spring Boot, REST APIs, JSON REST APIs, APIs, AWS SDK, Full-stack Development, CI/CD Pipelines, JavaScript, SaaS, Back-end, Architecture, Databases, Amazon RDS, Front-end Development, API Design, Back-end Development, Solution Architecture, IntelliJ IDEA, REST

Full-stack Software Developer and Freelancer

2015 - 2016

Igo4Health

Developed the IGO4HEALTH Health Tourism portal. Designed and sold to an international customer, it contains an admin panel, a hospital access panel, a website, and a mobile application for iOS and Android. It targets health tourism and packages services for people seeking health services.

Technologies: MySQL, NGINX, Ionic, AngularJS, Node.js, REST APIs, JSON REST APIs, APIs, Full-stack Development, JavaScript, SaaS, Back-end, Architecture, Databases, Amazon RDS, Front-end Development, API Design, Amazon CloudFront, Back-end Development, User Interface (UI), Angular Material, IntelliJ IDEA, REST, Mobile Development

Full-stack Software Developer and Product Manager

2014 - 2016

SIEMENS AG

Implemented the ITA-MOR web app. The app is used for IT device management, management of PCs, and smart mobile assets of Siemens AG. The product is used in Austria, Russia, and Turkey regions of Siemens.
Managed the development process of the Milion project. Incorporated the business strategy management and business strategy process of Siemens Turkey on this web application product. Defined the software development guideline, inspected delivered codes and documents, and imposed standards on developers to ensure product quality.
Took product owner responsibility of several IT Java web applications. These applications were handed over and several CR packages were developed for these products and provided support to the customers.

Technologies: Oracle Database, MySQL, Apache Tomcat, Spring, Hibernate, Bootstrap, PrimeFaces, JSF, REST APIs, JSON REST APIs, APIs, Full-stack Development, JavaScript, Back-end, JPA, Databases, Apache Struts 2, Front-end Development, Jira REST API, Back-end Development, User Interface (UI), OAuth, IntelliJ IDEA, REST

Senior Software Developer

2013 - 2014

Nortel Networks - Netaş

Analyzed the project's base modules, database design (using power designer), and mockup design for customer negotiation. Worked on proof of concept (POC) studies of tricky modules such as DB logging POC with Spring aspect-oriented programming, organization Chat POC (XMPP chat server and WebLogic server integration, web push technologies, chat DB design), Mailbox POC (DB and API design), and Spring EhCache integration.

Technologies: XMPP, Oracle Database, WebLogic, PrimeFaces, OmniFaces, JSF, Spring, Apache Maven, Spring Boot, JSON REST APIs, APIs, Full-stack Development, Back-end, JPA, Databases, Front-end Development, Back-end Development, User Interface (UI), Eclipse IDE

Full Stack Software Developer & Architect

2012 - 2013

Nortel Networks - Netaş

Developed the KKTC E-Nüfus project, a population registration system for the Turkish Republic of Northern Cyprus (KKTC). The project was developed with one former senior developer (me), two testers, and three other developers hired later. This is the civil registration of vital events in Cyprus like birth, death, marriage, divorce, adoption, legitimation, recognition, etc. Acts like immigration, emigration, and change of residence are registered in the system. Also, all the population registries of the country are digitalized with this product.

Technologies: JAX-WS, Web Services, jQuery, PrimeFaces, JSF, Spring JDBC, Apache Maven, PostgreSQL, Spring Boot, APIs, Full-stack Development, Back-end, Databases, NetBeans, Front-end Development, Highcharts, Enterprise Java Beans (EJB), Back-end Development, User Interface (UI), Eclipse IDE

Senior Software Developer

2010 - 2012

Nortel Networks - Netaş

Implemented a Swing framework-based JNLP client for Turkcell Technology. This Swing Client was developed for Turkcell Ayna Project and provides management, monitoring, paginated lazy data listing, filtering, and reporting modules; also developed a perfect dynamic auto-refreshing dashboard within this client using JfreeChart library.
Implemented a GSM service manager product for Turkcell Technology. Different IP-based services of Turkcell and their underlying application layer delivery protocols are defined with a common pattern named “Extensible Service Definition Language” (ESDL) which is basically an XML-based definition language that uses a basic XML Schema Definition (XSD) as a template for all service definitions. A user interface was developed for such a requirement with jQuery/UI and CSS3.
Contributed to the Turksat E-Devlet Secure XML Gateway project. Developed system management user interface phase. JSF2.0 framework and Primefaces 3.2 component suite are used.
Developed and designed several POC codes with jQuery and JSP Servlet stack for Turkcell, Turksat, and THY projects in national R&D of Netaş.

Technologies: Balsamiq, Wireframing, XML, Servlet, Jakarta Server Pages (JSP), CSS3, User Interface (UI), jQuery, JFreeChart, Java Natural Language Processing (JNLP), Swing, Spring Boot, Full-stack Development, Databases, NetBeans, Front-end Development, Highcharts, Eclipse IDE

Senior Software Developer

2010 - 2012

Nortel Networks - Netaş

Developed the UI and services of the Turkcell End To End Monitoring project. This is a GSM service data monitoring and management, deep packet inspection project, developed with two other colleagues.

Technologies: Oracle Database, Jakarta EE, WebLogic, PrimeFaces, JSF, Spring Boot, Full-stack Development, Databases, TCP/IP, NetBeans, Front-end Development, Highcharts, Enterprise Java Beans (EJB), Eclipse IDE

Senior Software Design and Development Engineer

2008 - 2010

Nortel Networks - Netaş

Intensively worked on an ATCA (advanced telecommunications computing architecture) project. The ATCA project is the hardware and operating system migrations of the next generation VoIP call server of Nortel Networks, namely gateway controller product (consists of 8 million lines of mainly C/C++ code).

Technologies: VoIP, Linux, C++, C, Full-stack Development, TCP/IP

Researcher and Software Developer

2007 - 2008

Liris-CNRS, Lyon France

Developed an object description and detection algorithm using local image features like SIFT and SURF.

Technologies: Tracking, Object Detection, Sift Science, Image Processing

Experience

IEEE Conference

R. Yildiz, T. Acarman, Image Feature Based Video Object Description and Tracking, IEEE International Conference on Vehicular Electronics and Safety, July 24-27 2012, Istanbul Turkey

Book Chapter

Feature-Based Robust Description and Monocular Detection: An Application to Vehicle tracking.

HYBRID INTELLIGENCE FOR IMAGE ANALYSIS AND UNDERSTANDING.
.
Ramazan Yıldız, Tankut Acarman, Pages: 187–203, 2017 Published Online: 14 AUG 2017, DOI: 10.1002/9781119242963.ch8

Puppeteer App with Node.js 12 and AWS Lambda Serverless

I have developed a web portal that is deployed to AWS. This portal is running on AWS and it has a sign-up feature for B2B customers. B2B customers fill out their pieces of information during sign-up. They provide their tax numbers, tax office. Using these inputs their validity is checked with a Node.js application that I developed. Tech stack used include: Puppeteer, Node.js 12, AWS Lambda Serverless Deployment with AWS API GW. Basically, this Node.js app does web scrapping and validates applying B2B users company details from the public portal of the Revenue Administration Portal.

Education

2011 - 2013

Master of Science Degree in Computer Vision, Image, and Real-time Video Image Processing

Galatasaray University - Istanbul, Turkey

2007 - 2008

Master of Science Degree in Computer Vision and Image Processing

INSA of Lyon (National Institute of Applied Sciences of Lyon) - Lyon, France

2003 - 2007

Bachelor of Science Degree in Computer Engineering

Galatasaray University - Istanbul, Turkey

Skills

Libraries/APIs

Node.js, React, REST APIs, Google Maps API, Auth0 API, OpenAI API, Puppeteer, RxJS, jQuery, Restify, Highcharts, Chart.js, Jira REST API, GSON, Snap.svg, Google Maps, JAX-WS, Java Natural Language Processing (JNLP), JFreeChart, PrimeNG, Socket.IO, NgRx/store, Telegram Messenger API, Jenkins Pipeline, Java Message Service (JMS)

Tools

Apache Maven, GitLab, Angular CLI, Amazon Virtual Private Cloud (VPC), Amazon Cognito, Amazon CloudFront CDN, AWS CLI, IntelliJ IDEA, Amazon Simple Notification Service (SNS), GitHub, Amazon CloudWatch, Amazon CloudFront, Capacitor, Auth0, AWS SDK, Amazon Elastic Block Store (EBS), Git, GitLab CI/CD, Amazon Simple Queue Service (SQS), Eclipse IDE, Apple Push Notifications, Amazon Simple Email Service (SES), Apache Tomcat, Zuul, Amazon EKS, Figma, Amazon Elastic Container Service (ECS), VPN, NGINX, Boto 3, Servlet, Balsamiq, Sift Science, Sequelize, Jenkins, AWS Transfer Family, Knex.js, Docker Compose, Terraform, Grafana, ActiveMQ, Microsoft Intune, Bitbucket, Amazon Elastic Container Registry (ECR), Azure Kubernetes Service (AKS), AWS Step Functions, Sentry, AWS Cloud Development Kit (CDK), Keycloak

Languages

Java 8, TypeScript 3, JavaScript, HTML5, Java, TypeScript, SQL, CSS, HTML, SCSS, Python, TypeScript 2, VB.NET, CSS3, XML, C, C++, Python 3, GraphQL, Java 11, Java 21, Go

Frameworks

Ionic, Angular, Angular Material, Spring Boot, Tailwind CSS, Express.js, JPA, JavaScript MVC, OAuth 2, Vaadin, Ionic 3, Spring, NestJS, Jest, Swagger, Hibernate, Bootstrap, Spring JDBC, Swing, Jakarta Server Pages (JSP), AngularJS, JSF, PrimeFaces, Cypress, Next.js, Apache Struts 2, Thymeleaf

Paradigms

Mobile Development, REST, Agile, Scrum, Responsive Web Design (RWD), Agile Software Development, Back-end Architecture, Functional Programming, Test-driven Development (TDD), Microservices, Microservices Architecture, Continuous Integration (CI), Continuous Delivery (CD), Functional Reactive Programming, ETL, Serverless Architecture, DevSecOps, User Acceptance Testing (UAT)

Platforms

Amazon Web Services (AWS), Amazon EC2, Oracle, Mobile, Amazon, Android, iOS, AWS Lambda, Docker, Linux, Twilio, NetBeans, Oracle Database, Jakarta EE, Firebase, Azure, Google Cloud Platform (GCP), Kubernetes

Storage

MySQL, Spring Data, Spring Data JPA, PostgreSQL, Databases, Database Structure, Amazon S3 (AWS S3), CouchDB, Amazon DynamoDB, PouchDB, Amazon Aurora, Redis Cache, Microsoft SQL Server, NoSQL, Oracle 12c, Firebase Realtime Database, Redis, SQLite, MongoDB, Spring Data MongoDB, Datadog

Other

API Gateways, User Interface (UI), Amazon Cognito User Pools, Amazon API Gateway, AWS Certificate Manager, Web Development, Mobile App Development, AWS DevOps, Full-stack, Production Support, Cordova, Front-end, JSON REST APIs, Helidon, Front-end Architecture, APIs, Front-end Design, Full-stack Development, CI/CD Pipelines, SaaS, API Integration, Back-end, Architecture, PWA, Amazon RDS, SSL Certificates, Vite, Authentication, Authorization, Front-end Development, CSV File Processing, CSV, Data Visualization, WebSockets, Product Engineering, API Design, Back-end Development, System Architecture, Software Architecture, Solution Architecture, Content Delivery Networks (CDN), Web Application Firewall (WAF), Technical Leadership, OAuth, Cloud, Cloud Platforms, Integration, Multi-factor Authentication (MFA), Tracking, Web Scraping, Angular Bootstrap, SSL, Algorithms, Videos, Data Scraping, SDKs, Team Leadership, User Experience (UX), TCP/IP, Single Sign-on (SSO), Scraping, Video Streaming, Order Management, Serverless, Amazon Route 53, Load Balancers, SAP, RESTful Services, Telnet Protocol, ODP.NET, VoIP, Web Services, Wireframing, OmniFaces, XMPP, Image Processing, Object Detection, DocumentDB, WebLogic, Gatsby, Apollo, Material Design, SFTP, AWS VPN, Virtual Threads, Ionic 7, Progressive Web Applications (PWAs), NATS, Infrastructure as Code (IaC), GitHub Actions, Prometheus, Vulnerability Assessment, Web App Development, SFTP Integration, Workday, QuickFIX, Natural Language Processing (NLP), Human-machine Interface (HMI), Software Engineering, Performance Analysis, Robotics, Image Synthesis, Advanced Modelization, Geometry, Image Analysis, Multimedia Compression, Software Development, Engineering, Mathematics, Computer Science, Information Retrieval, Computer Networking, Video Processing, Microsoft Entra, Enterprise Java Beans (EJB), OBJ Format

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