About Kostas
I'm a Principal Software Engineer with over a decade of experience designing scalable platforms, leading DevOps and infrastructure initiatives, and building secure, production-grade AI and agentic systems using LLMs, RAG, LangChain and bespoke MCP servers.
I've led organization-wide Kubernetes replatformings, automated GitLab and Jenkins migrations, and enhanced observability in legacy PHP systems, some of which I’ve open-sourced. I thrive at the intersection of software, platform engineering and applied AI, where I can bring clarity, speed, and reliability to software delivery and AI-augmented workflows.
In recent years, I’ve driven the adoption of AI agents and automation across engineering teams, delivering real impact through secure agentic flows, custom Slack assistants, and company-specific MCP integrations.
I've led multiple teams at once, supported hundreds of engineers in large-scale platform orgs, and thrived in startup environments with high autonomy and deep ownership. Whether guiding DevOps transformations across departments or helping small teams move fast with strong foundations, I’ve learned how to lead and adapt to different cultures, and deliver real impact, no matter the org size or structure.
English
Native or bilingual
Greek
Native or bilingual
Remote only
Primarily works remotely
Experience
- SportservePrincipal Software EngineerTECHSeptember 2022 - Today (3 years and 9 months)Greece
- Led the design, implementation and hardening of AI agentic flows using Codex, n8n, LangChain, RAG and MCP servers, ensuring alignment with organizational security, privacy and compliance standards.
- Researched and prototyped emerging LLM, RAG, MCP and agentic techniques to improve internal tools and chatbots.
- Built custom Slack AI assistants in Go that integrated with internal systems to streamline onboarding, reduce manual load for senior engineers and provide contextual, real-time support to new hires.
- Founded the platform architecture forum and principal engineers group, enabling cross-team alignment, clearer tradeoff discussions, and faster architectural decision-making across the org.
- Reduced lead time for engineering requests from weeks to minutes by launching #ask channels for each platform team, promoting transparency, faster support, and a shift toward collaborative, service-minded culture.
- Drove the strategic roadmap and replatforming of application services to Kubernetes, enabling greater agility and positioning the org for hybrid and multi-cloud deployments.
- Extended legacy PHP 7.2/Drupal 7 applications with deep APM telemetry and built a custom OpenTelemetry collector to enable tracing support, improving stability for 10x seasonal traffic events and promoting wider observability adoption across the org.
- Improved critical application performance by identifying and addressing bottlenecks, more than doubling traffic capacity and improving response times.
- Built a Go-based service to ingest GitLab webhook events into our telemetry stack, significantly improving visibility and platform team's response times for GitLab operations (Go, Kubernetes, Elasticsearch)
- Engineered tooling for automating Jenkins to GitLab SaaS migration, including data analysis, migration steps, and reporting (Go, Elasticsearch)
- Created reusable Helm charts and GitLab pipeline jobs to standardize and scale application deployments across teams (Helm, FluxCD, Gitlab)
- OpenBetDevOps Team LeadTECHJanuary 2021 - July 2022 (1 year and 6 months)Greece
- Worked at the center of the company's sportsbook product. Implemented, designed and proposed a number of initiatives to accelerate customer delivery.
- Organized multiple departments to create representative CI/CD environments with automation testing for customers having highly customized solutions.
- Maintained new and existing CI/CD environments. Delivered slack bot automation, in python, for effective triaging of errors raised during continuous deployments.
- Lead a team of 9 DevOps engineers working in the CI/CD space. Provided environments using AWS EC2, internal deployment tooling using python and AWS, EKS Kubernetes clusters for use in CI/CD and testing tooling.
- Under the head of DevOps, managed the project to transition the product architecture from VM based to Kubernetes. Lead a team of 5 principal engineers and 3 senior engineers designing and implementing the transition.
- Fantasy Sports InteractiveSenior Solutions ArchitectTECHJanuary 2020 - December 2020 (11 months)Greece
- As a member of a small team of autonomous engineers tasked with the creation of a fantasy sports platform
- Developed new Java Spring microservices from the ground up.
- Reduced AWS costs by 30% and categorized our infrastructure.
- Architected our website product offering and a part of our B2B feed offering.
- Architected and implemented the integration testing solution, covering both RESTful and event-driven services and contributed to open source test automation.
- Designed and implemented the CI/CD pipeline, allowing our full test-suite to run against each commit.
- Performed DevOps activities which included the use of Terraform, AWS, docker compose, docker swarm and Kubernetes
- Co-defined our software development lifecycle.
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Education
- B.Sc.Ethnikon kai Kapodistriakon Panepistimion Athinon2011B.Sc.
- Machine LearningCoursera2026Machine Learning