Stefan Aygül

Experience

• 

  Türk Telekom International

  Aug 2013 - Sept 2013

  Intern
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  Netas

  Sept 2014 - Dec 2014

  Engineering Intern
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  NETAŞ

  Feb 2015 - Nov 2017

  • DevOps Engineer

    Apr 2017 - Nov 2017

  • Lab Operations Engineer

    Feb 2015 - Mar 2017
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  UITSEC Security Technologies Group

  Nov 2017 - Dec 2018

  DevOps Engineer
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  AirTies Wireless Networks

  Dec 2018 - Mar 2020

  DevOps Engineer
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  Domino's

  Mar 2020 - Sept 2020

  DevOps Engineer

  A pivotal undertaking involved the migration from Azure App Service to Kubernetes, marking a significant transformation. I orchestrated the creation of a meticulously designed network infrastructure on Azure, shaping IAM roles in conjunction with Azure AD. Additionally, I orchestrated the seamless migration of on-premises databases to Azure, facilitated by the creation of AKS using Terraform. In tandem, I meticulously crafted Dockerfiles for microservices, subsequently uploading them to the container registry. Designing and enacting Kubernetes manifests, as well as overseeing the entirety of CI/CD procedures through Azure DevOps, were also central aspects of this initiative. This transformation yielded substantial savings of $20,000 per month. The entirety of these processes, from design to management, was carried out single-handedly• Manage Azure App Service to Azure Kubernetes Transformation • Experienced working in Azure cloud computing platform and many dimensions of scalibility including Azure VM, Azure Virtual Network, Express Route, App Service, AKS, Azure AD, Application Insights, Azure Application Gateway. • Deployed and managed applications running on Azure Kubernetes Service and introduced optimization; resulted in a $20k savings per month• Install and configure Prometheus+Grafana with Helm on AKS• Deploy APM tool which is New Relic to AKS and Virtual Machines• Devoloping kubernetes dockerfile and kubernetes manifests for AKS transformation• Developing scripts with bash• Create and maintain fully automated CI/CD pipelines for code deployment using Azure Devops• Configure alertmanager to get critical alerts • Configured Linkerd,which is service mesh on Kubernetes cluster• Experienced with Velero to take backup of the Kubernetes clusters• Check the risk of the kubernetes cluster with kube-scan Show less

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  Vodafone

  Sept 2020 - Mar 2022

  DevOps Engineer

  I was part of a global initiative at Vodafone known as VF Happy. In this role, I was responsible for devising and executing the entire CI/CD process using Jenkins. For robust logging, I integrated Fluentd, along with Kafka and Splunk. The monitoring framework was built using Splunk and Instana for APM (Application Performance Monitoring). In the realm of microservices deployment, I leveraged Kubernetes (EKS). Crafting meticulous manifests, including Deployments, Services, Ingress, Network Policies, and RBAC, was a key aspect. These were designed adhering to best practices, encompassing non-root privileges, anti-affinity rules, and the strategic use of Kyverno for resource management, limitations, deployment strategies, and more, all while ensuring top-notch security. The installation of the infrastructure was automated using Terraform modules. Currently, the system is live and seamlessly handles a minimum of 3 million daily requests.- Designing and Deployment of OpenShift and EKS. During designing the microservices deployment to Kubernetes, writing all manifest (Deployment, Services, Ingress, Network Policies, RBAC etc.) with best practices (non-root privileges, anti-affinity rules, resource and limitations management with Kyverno, deployment strategies.) and secure way. - Drive DevOps adoption by recommending and implementing tool sets and best practices for automation, configuration and release management - Develop and manage consistent and coherent DevOps processes and practices to support software development, testing, builds and deployment - Raising the team's knowledge about DevOps culture and new tools by training the team - Manage Docker Swarm to OpenShift Transformation - Write Dockerfiles and yaml files for Openshift Transformation - APM (Appdynamics, Dynatrace) - Create and maintain fully automated CI/CD pipelines for code deployment using Jenkins (jenkinsfile) - Developing scripts with Shell - Configure EFK for logging Show less

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  Pensa Systems

  Mar 2022 - now

  DevOps Engineer

  Pensa Systems is a company that specializes in autonomous perception systems and artificial intelligence solutions for retail and consumer goods industries. My role entails integrating and configuring services hosted on both AWS and Azure platforms. I oversee the management of these environments using Terraform, adhering to a well-defined structure. I actively contribute to the deployment of new microservices via ECS, and I'm involved in implementing various CI/CD pipelines such as Code Pipeline, GitHub Actions, Azure DevOps, and CircleCi. Additionally, I handle aspects like monitoring and logging through CloudWatch and Datadog, while also configuring Lambda functions and SQS components.- The majority of our infrastructure is hosted on Amazon Web Services (AWS), encompassing a wide array of essential services. Among the prominent AWS services employed are EC2 for various purposes, IAM for identity management, S3 for storage, Elastic Container Service (ECS) for container orchestration, VPC for networking, CloudWatch for comprehensive monitoring, Event Bridge for event-driven architecture, Lambda for serverless computing, SQS for message queuing, Amplify for app development, Cognito for user authentication, Elastic Kubernetes Service for managed Kubernetes, System Manager for operational management.- Some of infrastructure operates on Azure, utilizing key services like Azure Virtual Machines, Vnet (Virtual Network), Azure Database for PostgreSQL, Azure Functions. - Migration from Azure Database for PostgreSQL Single Server to Azure Database for PostgreSQL Flexible Server - Terraform is the key Infrastructure as Code tools during implementing the services to cloud providers. Managing the all implementations and deployments with terraform files. - Create and maintain fully automated CI/CD pipelines for code build and code deployment using Codebuild, Github Actions and Azure DevOps - Design and implemention strategy for Kafka on Confluent and integrate it. Show less