Hasan-Basri Caglayan

Migration from PHP to Go for the BFF (Back For Front) of a high-volume streaming platform to improve scalability and reduce infrastructure costs.

• Bedrock operates the streaming services for M6 and RTL groups for over 50 million users in Europe.

• Developed in PHP, the BFF is the entry point for frontend applications and orchestrates calls to numerous microservices.

• Bedrock initiated a redesign to introduce a Go proxy, reduce operational costs, and prepare the BFF's migration to Go.

• Designed an architecture based on DDD principles to facilitate the BFF migration.

• Developed a Go proxy intended to become the new entry point for front applications.

• Implemented unit and integration tests in Gherkin, ensuring the platform's reliability and non-regression.

• Deployed and configured the proxy on K8s using Helm in an AWS cloud environment.

• Provisioned and configured cloud resources with Terraform.

• Set up API routing via Gloo Gateway (HTTPRoute) and DNS configuration via AWS Route 53 to expose the proxy and route traffic to backend services.

• Served as the team's reference for load and performance testing, responsible for validating the new architecture's robustness up to 6,000 users/second.

• Designed and implemented load testing scenarios in Java with Gatling to simulate realistic traffic volumes and anticipate peaks related to major events like the 2026 World Cup.

• 10% reduction in infrastructure costs thanks to the initial proxy versions put into production.

• Improved platform resilience, strengthening its robustness against traffic spikes.

• Established a structured load testing framework, ensuring the reliability and longevity of platform evolutions.

• Go, Golang, Kubernetes, Helm, AWS, Terraform, Gloo Gateway, Route 53, Java, Gatling, Gherkin, DDD

Design, development, and maintenance of a cloud-native multi-tenant SaaS application based on an event-driven microservices architecture.

• Hardis Group is a major player in software publishing for the Supply Chain and Logistics industry with its subsidiary Hardis Supply Chain.

• The Hardis WMS (Warehouse Management System) software was launched in 1994 and deployed on Google Cloud Platform in 2023 in its SaaS version.

• The goal is to evolve Hardis WMS SaaS to meet customer needs, following the "You Build It, You Run It" approach.

• Developed gRPC and REST APIs with Protobuf modeling, optimizing communication between distributed systems and reducing exchange latency.

• Implemented resilient and scalable workflows in Go with Cadence, enabling the execution of complex, concurrent, and asynchronous business processes.

• Designed and evolved microservices in Go within a distributed architecture, integrating Apache Pulsar for event streaming and Apache Flink for real-time stream processing.

• Implemented comprehensive unit tests, improving code robustness and reducing regressions.

• Deployed and orchestrated Docker containers on Kubernetes (GKE) using Helm, ensuring a highly scalable architecture.

• Optimized CI/CD pipelines via GitLab CI/CD, enabling continuous, large-scale production deployment.

• Utilized ClickHouse and Grafana for real-time monitoring and observability.

• Golang, Cadence Workflow

• GitLab CI/CD, Docker, Kubernetes, Helm, Google Cloud Platform (GCP)

• PostgreSQL, Cassandra, OpenSearch

• ClickHouse, Grafana

Design and development of an online clothing sales web application.

• This project was carried out for Atos, a French IT consulting company also operating internationally.

• The goal is to develop a quality web application in compliance with specifications, using C#, .NET, and Angular technologies.

• Created use case and class diagrams for the application.

• Set up and configured a SQL Server database with Entity Framework Core using a Code First approach.

• Developed a REST API with ASP.NET Core using the Repository Pattern to isolate the data access layer from the business logic layer and facilitate application maintenance.

• Integrated JWT (JSON Web Tokens) into the web API to ensure secure user authentication.

• Developed an Angular application following a modular architecture with structured component breakdown for extensible source code.

• Implemented Angular's Lazy Loading to speed up application loading time and improve performance.

• Created a user-friendly, intuitive, and responsive user interface with Bootstrap.

• Managed the application's source code with GitHub.

• Project delivered on time.

• Created an application that meets all specifications.

• C#, ASP.NET Core, LINQ, Entity Framework Core

• SQL Server

• TypeScript, Angular, RxJS, Bootstrap

• GitHub