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Ismail Yenigul, AWS and Linux Developer in Istanbul, Turkey
Ismail Yenigul

AWS and Linux Developer in Istanbul, Turkey

Member since July 31, 2020
Ismail is a senior DevOps engineer with Linux, AWS, and Kubernetes expertise. His recent projects focused on AWS, Terraform, CI/CD, DevSecOps, and the Google Cloud Platform, and he is proficient in ArgoCD, AWS EKS, GKE, Jenkins, Docker, and Helm. Ismail is a certified Kubernetes application developer (CKAD), a certified Kubernetes administrator (CKA), an AWS certified solution architect, and an AWS certified developer with a motto: "Leave no stone unturned to fix issues."
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Portfolio

  • Freelance
    Jenkins, Terragrunt, Packer, Amazon Web Services (AWS), GitHub...
  • Vision R&D
    Security, System Administration, Microsoft SQL Server, GitLab, Jira, Python...
  • Esys
    Security, System Administration, DNS, SMTP, Web, Red Hat Linux, Linux, LPIC-1...

Experience

Location

Istanbul, Turkey

Availability

Part-time

Preferred Environment

Amazon Web Services (AWS), Continuous Delivery (CD), Continuous Integration (CI), Terraform, Google Cloud, AWS, Linux, Google Kubernetes Engine (GKE), Amazon EKS

The most amazing...

...projects I've done focused on building secure and reliable AWS infrastructures with Terraform.

Employment

  • Senior DevOps Engineer | Site Reliability Engineer

    2016 - PRESENT
    Freelance
    • Deployed, automated, managed, and maintained a cloud-based production system, using AWS, Google Cloud, Azure, and DigitalOcean.
    • Ensured availability, performance, security, and scalability of production systems, focusing primarily on Linux environments.
    • Troubleshot systems and resolved problems across various application domains and platforms. Tracked and fixed issues, using Jira and GitHub.
    • Migrated from a manually managed system to a fully automated platform which included creating CI/CD pipelines with Jenkins, GitHub Actions, Argo CD, Flux, Harness, and application of GitOps methodology.
    • Managed EKS, ECR, ECS, GKE, DigitalOcean Kubernetes, Docker, and Docker Compose deployments.
    • Deployed AWS infrastructure (EKS, EC2, RDS, CloudFront, Route53, OpenVPN, IAM roles/policies and VPC) with Terraform.
    • Deployed GKE clusters, Cloud SQL, LoadBalancer, and Compute Engine, and configured GitLab to push Docker images to the container registry.
    • Built Docker images and deployed them to AWS Fargate with GitHub Actions.
    • Created a Docker build pipeline with GitHub Actions, CircleCI, and Jenkins.
    • Applied AWS security best practices and CIS compliance requirements; configured AWS Security Hub, AWS Config, and VPC flow; and hardened GKE cluster security.
    Technologies: Jenkins, Terragrunt, Packer, Amazon Web Services (AWS), GitHub, System Administration, Cloud Security, Docker, Continuous Delivery (CD), Continuous Integration (CI), Linux, AWS Fargate, Kubernetes, Amazon EKS, Terraform, DevOps, Google Cloud Platform (GCP), AWS, AWS DevOps, AWS Certified Solution Architect, Ubuntu Server, GitHub Actions, AWS Transfer for SFTP, Postfix, IT Security, NGINX, Zabbix, Google Kubernetes Engine (GKE), Docker Compose, AWS ELB, AWS CloudTrail, Docker Hub, Amazon ECS (Amazon Elastic Container Service), Shell, Gruntwork, OpenShift, CircleCI, AWS IAM, Amazon Virtual Private Cloud (VPC), Google Cloud SQL, Amazon ECR (Amazon Elastic Container Registry), Containers, CI/CD Pipelines, Linux Server Administration, Site Reliability Engineering (SRE), Argo CD, HAProxy, SecOps, Nagios, Datadog, SonarQube, Jenkins Pipeline, Harness CI/CD, DigitalOcean, Amazon EC2 (Amazon Elastic Compute Cloud), Amazon CloudWatch, AWS SES, MongoDB Atlas, Flux, Ubuntu, Git, Redis, MongoDB, Bash Script, CIS Security, Jira, Ansible, AWS Elastic Beanstalk, AWS CodePipeline, AWS CloudFormation, OpenVPN, Bitbucket, Cloudflare, GitOps, DevSecOps, GitLab CI/CD, VPN, Identity & Access Management (IAM), Python, Helm, Continuous Development (CD), Azure, Bash, Containerization, AWS RDS, CentOS, SendGrid, RHEL, Microservices, Site Reliability, Leadership, Continuous Deployment, AWS Elastic File System, Relational Database Services (RDS)

  • Technical Team Lead and DevOps

    2010 - 2016
    Vision R&D
    • Established the technical vision and provided leadership to department heads.
    • Built the development platform and managed the project, using Jira, Confluence, and GitLab.
    • Managed the software development and quality assurance teams.
    • Identified and integrated new technologies to drive the business strategy and enhance client relationships.
    Technologies: Security, System Administration, Microsoft SQL Server, GitLab, Jira, Python, PHP, Git, Ubuntu, Red Hat Linux, Linux, MySQL, Postfix, IT Security, NGINX, AWS ELB, Shell Scripting, Linux Server Administration, Site Reliability Engineering (SRE), HAProxy, Nagios, AWS SES, DevOps, Redis, Docker, Amazon EC2 (Amazon Elastic Compute Cloud), MongoDB, Bash Script, Ubuntu Server, CIS Security, DigitalOcean, Google Kubernetes Engine (GKE), Cloud Security, OpenVPN, Bitbucket, Cloudflare, VPN, Bash, Containerization, CentOS, SendGrid, RHEL, Microservices, Site Reliability, Leadership, Continuous Deployment

  • Linux/Unix System Administrator | Site Reliability Engineer

    2007 - 2010
    Esys
    • Designed and managed a Linux (Red Hat, CentOS, and Ubuntu) and Unix infrastructure.
    • Maintained security and mitigated threats as new ones were identified.
    • Improved infrastructure services, performance, and reliability.
    • Became a Master Affiliate of The Linux Professional Institute (LPI), managed the company's training partner relationship with the institute, and grew the Linux and FOSS communities—all in Turkey.
    • Installed and maintained web, DNS, SMTP Server, and FTP on Linux.
    • Assisted with shell scripting for a system and application used to automate server tasks.
    • Created and maintained a secure and reliable Linux environment. Managed daily activities, including user support and system administration tasks.
    Technologies: Security, System Administration, DNS, SMTP, Web, Red Hat Linux, Linux, LPIC-1, SSH, Ubuntu Linux, Git, Ubuntu Server, IT Security, NGINX, Zabbix, Linux Server Administration, Site Reliability Engineering (SRE), Nagios, AWS SES, Ubuntu, Redis, MongoDB, Bash Script, CIS Security, Qmail, OpenVPN, VPN, Bash, CentOS, SendGrid, RHEL, Site Reliability, Leadership

  • International DSL TAC Engineer

    2003 - 2007
    Alcatel Lucent
    • Managed the Unix servers for AWS products deployed for telecom operators.
    • Provided Unix and Linux support remotely or on-site in the EMEA region.
    • Matured into a successful and valued member of the Unix/DSL support team in the EMEA region.
    Technologies: Linux, Networks, Domain-specific Languages (DSLs), Unix, Solaris, NGINX, Site Reliability Engineering (SRE), Bash Script

  • Software Developer

    2002 - 2003
    Oyak Teknoloji
    • Developed host switch servers for debit and credit card systems in C++.
    • Built a banking software solution based on internal customer requirements.
    • Increased the performance of the process, which increased customer satisfaction, gained loyal customers, and maximized profitability.
    Technologies: Unix, C++, Oracle, Qmail

  • Unix/Linux Systems Administrator and Developer

    2000 - 2002
    RT.NET
    • Participated in designing, implementing, securing, and maintaining Linux and the Solaris ISP for its test, development, and production environment.
    • Provided Linux, Solaris, and infrastructure support for internal and external clients.
    • Created and modified scripts and applications to perform tasks.
    • Improved the stability, security, efficiency, and scalability of the environment.
    Technologies: System Administration, PostgreSQL, MySQL, Perl, Shell Scripting, Microsoft SQL Server, Shell, Postfix, Qmail, Web, DNS, FreeBSD, Linux, Solaris, Ubuntu Linux, Bash Script, CentOS

Experience

  • CIS Compliant AWS Infrastructure

    I redesigned and built an AWS infrastructure by using AWS Reference Architecture and best practices with Terraform modules. The AWS components included EKS, ECR, S3, Config, Security Hub, IAM, GuardDuty, VPC Flow, RDS, and ELB.

  • Migration from docker-compose to AWS EKS cluster

    I was a Devops engineer in this project. Apps were running on single EC2 instance with docker-compose.

    Task accomplished:

    Migrated all docker-compose files to k8s manifests.
    Deployed AWS EKS cluster with the following components:
    AWS Load Balancer Controller
    Sealed Secret to keep secrets encrypted on git repository.
    External DNS to manage route 53 records automatically
    Argo-CD to implement GitOps methodology
    IAM assume roles to access EKS cluster

    Everything deployed with terraform

  • Implement IaC Scanner for terraform codes for AWS resources

    I was a DevSecOps engineer in this project.
    I used checkov to scan terraform codes on each git push and Harness deployment

    Checkov is a static code analysis tool for infrastructure-as-code.

    It scans cloud infrastructure provisioned using Terraform, Terraform plan, Cloudformation, AWS SAM, Kubernetes, Helm charts,Kustomize, Dockerfile, Serverless, Bicep or ARM Templates and detects security and compliance misconfigurations using graph-based scanning.

    I implemented terraform scanning in GitHub Actions on every push.
    Also created scripts to use in Harness pipeline to check terraform code security before deploying apps to AWS
    I also contributed checkov open source project by submitting code fix PR, docs and feature requests.

Skills

  • Languages

    Bash Script, Bash, Python

  • Libraries/APIs

    Terragrunt, Jenkins Pipeline

  • Tools

    Git, Google Kubernetes Engine (GKE), Postfix, Docker Compose, GitHub, OpenVPN, Zabbix, AWS ELB, Terraform, AWS Fargate, Bitbucket, Amazon CloudWatch, AWS CloudTrail, Amazon ECS (Amazon Elastic Container Service), NGINX, MongoDB Atlas, Packer, AWS SES, Shell, Amazon EKS, CircleCI, Jenkins, GitLab, Docker Hub, AWS IAM, Amazon Virtual Private Cloud (VPC), Amazon ECR (Amazon Elastic Container Registry), GitLab CI/CD, Helm, SendGrid, Grafana, Jira, Ansible, VPN, AWS CloudFormation

  • Paradigms

    DevOps, Continuous Integration (CI), Continuous Delivery (CD), DevSecOps, Continuous Development (CD), Microservices, Continuous Deployment

  • Platforms

    Linux, Kubernetes, Docker, DigitalOcean, FreeBSD, Ubuntu Linux, Amazon Web Services (AWS), Amazon EC2 (Amazon Elastic Compute Cloud), Google Cloud Platform (GCP), Red Hat Linux, Ubuntu, Unix, CentOS, AWS Elastic Beanstalk, Solaris

  • Storage

    Google Cloud, MySQL, Amazon S3 (AWS S3), Redis, AWS Elastic File System, PostgreSQL, MongoDB, Google Cloud SQL

  • Industry Expertise

    Security, IT Security

  • Other

    AWS, System Administration, AWS Certified Solution Architect, LPIC-1, GitOps, Qmail, Shell Scripting, GitHub Actions, AWS DevOps, AWS Transfer for SFTP, SSH, Ubuntu Server, Cloud Security, Systems Monitoring, Cloudflare, CIS Security, Gruntwork, Containers, CI/CD Pipelines, Linux Server Administration, Site Reliability Engineering (SRE), Argo CD, Infrastructure as Code (IaC), SecOps, DevOps Engineer, Identity & Access Management (IAM), Containerization, AWS RDS, RHEL, Site Reliability, Leadership, Relational Database Services (RDS), Prometheus, AWS CodePipeline, HAProxy, Checkov IaC Scanner, SMTP, DNS, Networks, Computer Science, Harness CI/CD, Checkov

  • Frameworks

    Flux

Education

  • MBA in Business Administration
    2012 - 2014
    Istanbul Kemerburgaz University - Istanbul, Turkey
  • Bachelor's Degree in Computer Science
    1997 - 2003
    Istanbul Technical University - Istanbul, Turkey

Certifications

  • Certified Kubernetes Administrator (CKA)
    JUNE 2022 - JUNE 2025
    Cloud Native Computing Foundation
  • Certified Kubernetes Application Developer Certification (CKAD)
    FEBRUARY 2022 - FEBRUARY 2025
    Cloud Native Computing Foundation
  • AWS Certified Developer - Associate
    JANUARY 2018 - JANUARY 2020
    AWS
  • AWS Certified Solutions Architect - Associate
    JULY 2017 - JULY 2019
    AWS
  • The Linux Professional Institute — LPIC-1
    JULY 2011 - JULY 2016
    The Linux Professional Institute

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