Sinan Köylü

Infrastructure Scale & Management:

• Architected 100+ Kubernetes clusters across Production, QA, Development serving millions of daily financial transactions
• Designed multi-region, multi-AZ architecture ensuring 99.99% availability for payment processing systems
• Built centralized cluster management platform handling 2000+ microservices across all environments

FAST Payment System Migration:

• Led TCMB FAST payment system migration to Kubernetes achieving sub-2 second end-to-end latency
• Migrated legacy monolithic FAST components to containerized microservices with 10x throughput improvement
• Implemented event sourcing and CQRS patterns ensuring complete audit trails for FAST transactions
• Created specialized Kubernetes operators for FAST message queue management and transaction state handling

SealOctopus Security Platform:

• Architected Seal distributed authentication handling 50K+ concurrent sessions with MFA (SMS OTP, Push, Biometric)
• Designed Octopus real-time malware scanning for mobile banking processing 1M+ daily device attestations
• Built Kubernetes-based ML pipeline for behavioral analysis and threat detection
• Implemented OAuth 2.0/OIDC provider with custom token management and device fingerprinting

Observability & Legal Compliance:

• Migrated 100+ ELK stacks to OpenSearch with Fluent Bit and OpenSearch Dashboards
• Built S3 automation for legal log retention with daily backups meeting regulatory requirements (50TB+ daily)
• Implemented comprehensive observability with Prometheus, Grafana, and Thanos for long-term metrics
• Developed distributed tracing using Jaeger tracking payment flows across 30+ microservices

Infrastructure Migration & High Availability:

• Led CentOS to Ubuntu 22.04 migration for all Kubernetes clusters and stateful systems per audit compliance
• Implemented GSLB with NetScaler for redundant active-active load balancing across datacenters
• Designed zero-downtime migration strategy for 100+ production clusters maintaining service continuity
• Built disaster recovery for FAST system with RPO less than 30 seconds and RTO less than 2 minutes

DevOps Automation & Performance:

• Developed full-stack automation platform using Python/FastAPI backend and React/Next.js frontend
• Created GitOps pipeline using ArgoCD managing 500+ applications including FAST components
• Optimized FAST message processing achieving sub-100ms processing latency
• Achieved 40% cost reduction while maintaining performance SLAs through resource optimization
• Improved code deployment efficiency by automating processes with CI/CD pipelines.
• Automated manual tasks through scripting languages such as Python or Shell, boosting team productivity levels.
• Maintained version control systems like Git or SVN for seamless collaboration among developers and engineers during project lifecycles.
• Designed and implemented containerization strategies using Docker and Kubernetes, improving resource utilization and management.
• Reduced system downtime for critical applications by implementing robust monitoring and alerting tools.
• Monitored automated build and continuous software integration process to drive build/release failure resolution.
• Contributed to the creation of a DevOps culture within the organization, leading to increased agility and cross-functional collaboration.
• Provided 24/7 on-call support for critical systems, ensuring high availability and rapid issue resolution.
• Mitigated security risks by conducting regular vulnerability assessments and applying necessary patches.
• Optimized build processes using tools such as Jenkins or Bamboo for fast feedback loops in development cycles.
• Enhanced application performance by optimizing infrastructure configurations based on usage patterns.
• Collaborated with development teams to streamline software releases, resulting in faster timetomarket.
• Optimized resource usage by implementing and managing infrastructure as code, leading to cost efficiencies.
• Reduced operational costs by optimizing cloud resource utilization and implementing cost-effective solutions.
• Improved project visibility and tracking with implementation of comprehensive dashboards and reporting tools.
• Reduced system downtime with effective incident management and rapid response strategies.
• Fostered culture of collaboration and knowledge sharing among development and operations teams, boosting overall project success.

• Led deployment of analytics platforms involving Kafka, Druid, Spark, Flink, Hadoop, and ELK.
• Managed container orchestration via Kubernetes, Docker Swarm, and OpenShift on client sites.
• Oversaw CI/CD automation and infrastructure monitoring.

• Migrated infrastructure from OKD + Jenkins to Kubernetes + GitLab CI/CD.
• Managed PostgreSQL replication between clusters with Debezium and Kafka.
• Administered monitoring tools including Kibana, Graylog, Prometheus, Logstash, Fluentbit.
• Led API Gateway implementation (KrakenD), configuration management (Ansible), and infrastructure-as-code.
• Ensured 24/7 platform uptime.

• Supported OSS-based DevOps for Turk Telekom digital projects (TTSLA, TekilOIM, TTADR).
• Administered Kubernetes-based microservice environments with Kafka, MongoDB, Prometheus.
• Maintained 30+ Linux servers across 9 platforms.

• Migrated 400+ servers to Linux; PostgreSQL performance optimization.
• Managed GCP operations, Jenkins automation, and Zabbix for 800+ servers.
• Implemented centralized update systems with Spacewalk.

• Managed 50+ distributed servers; implemented Docker, Swarm, Kubernetes.
• Deployed ELK, Grafana, Zabbix, and Apache Superset for monitoring and BI.
• Automated test and failure response procedures.

• Delivered EMC backup solutions (Avamar, Networker, DataDomain) to Turk Telekom and other clients.
• Provided data protection consultancy and DR support.

• Led infrastructure and system integration for national public projects (MHRS, KYGM, Fatih Project).
• Implemented Oracle MW Suite (WebLogic, OAS, OID), clustering, HA and DR systems.

• Managed Vodafone's 3G network on M2000 platform with Solaris, Veritas HA, and NetBackup.
• Supported alarm and performance systems.