Giorgos Papaefthymiou Email & Phone Number

Athens, Attiki, Greece

As Team Lead and SME in Developer Experience, I led a team of 4 to enhance Developer workflows and elevate the Celonis Platform's Operational Efficiency. I introduced Backstage as the Internal Development Platform (IDP), establishing it as the primary resource for developers to access comprehensive Service and Team information, including documentation, APIs, deployments, and the organizational chart. This initiative drove an 80% monthly adoption rate in the Engineering Organisation.I led the evolution of the Service Catalog into a Single Source of Truth (SSOT) by integrating multiple data sources, ensuring accurate, up-to-date information. Transformed the Catalog into a Reactive Platform where stakeholders could define policies, track adoption, and implement action plans to drive technical excellence and policy compliance. It became critical in the Software Development Lifecycle (SDLC), supporting processes from Product Design to Deployment and Incident Resolution. It also enabled external systems to access real-time data on teams, services, and ownership, enhancing Decision Making and Operational Efficiency.As a line manager, I implemented OKRs to align business goals with team objectives, utilized skill gap analysis to identify growth opportunities, and balanced the development of both technical and soft skills within the team. I actively participated in hiring and contributed to improving onboarding processes, ensuring smooth integration for new team members. By fostering a culture of innovation and autonomy, I empowered the team to deliver impactful results while supporting continuous professional growth.

Athens, Attiki, Greece

Lead a team of 4 members responsible for the product development lifecycle.As DevOps we were responsible for:- Continuous integration: Building artifacts, run tests (unit, integration, blackbox, regression), report quality metrics Tools/services: Github actions, Jenkins- Software release lifecycle: Artifacts publishing, dependencies management, release channels (customer area, Docker registries, Helm repositories), documentation (release notes, upgrade notes)- Staging development environments: Run stable envs for demo purposes, ad-hoc envs for testing, each one with different version of services and dependencies.As SREs we were responsible for:- Infrastructure management: Infra As Code (Terraform), Cloud resources in GCloud / AWS and cost management, Users, groups and permissions- Continuous deployment using GitOps: Implement deployment flows (ArgoCD)- Monitoring, logging and tracing (Prometheus, Grafana, Elastic Stack, Datadog)As gatekeepers of the dev team’s culture, we were responsible of cultivating common best practices and provide reference implementations, documentation, presentations and trainings for:- Version control: Git, Github, Gitflow, Code review flows- Local development environments: Setup, Run locally using docker/docker-compose/Kubernetes, Run tests (shift left approach), Test-Driven Development (red-green approach)As part of the Lenses customer facing support team we were responsible for:- Managing the communication with the customer until any issue is resolved, join meetings to get requirements or perform investigations in customer systems.- Triaging customer issues and provide first-aid support on production instances deployed in on-premise infrastructure.- Identifying code issues and collaborating with the dev team in order to resolve them while providing work-arounds to the customer.

Athens, Attiki, Greece

- As the developer of the staging envs I gave to the dev team an easy yet powerful way to spin up any combination of Lenses version with any flavor of external services (Kafka brokers, Schema registry, Connect cluster) in under 5 minutes without any limitation on running instances. Dozens of services could run simultaneously in a cost-effective way. Also, implemented a cleanup feature to wipe unused envs when needed.- I have been the maintainer of Lenses Helm repo and introduced among other features tests and test coverage.- I have performed dozens of trainings to influence the dev team towards the best practices in software development lifecycle.

Athens, Greece

Introduced Kubernetes and moved all operations from Docker swarm to Kubernetes in AWS using Kops, Helm, Docker providing scaling and resiliency benefits.Owned the Software Lifecycle of the product using GitLab's CI/CD pipelines.Created a flexible yet powerful monitoring layer over Kubernetes using Prometheus, Grafana, Kibana, ElasticSearch providing a stable way to handle production issues.Implemented an alerting mechanism for technical and business metrics using Grafana, Nagios, PagerDuty and relevant tools

Athens, Greece

- Introduced Docker and orchestrated the transition of the development department to use Docker- Implemented the CI/CD pipeline for a Java application (Jenkins, Artifactory, Gradle, Haproxy)- Worked in core API engine which is responsible for the OTA Booking flow. (PHP Zend Framework)- Worked on client facing new frontend (React JS, Backbone JS, Ruby, Node JS)- Implemented/integrated multiple tracking mechanisms for Customer behaviour (PHP/Javascript frameworks)- Worked on Bolt, a web application to model the customer entity, provide real-time recommendations and prevent fraud (Java, Spring Boot with Gradle, Neo4J, RabbitMQ)

Athens, Greece

Supertasker (by PeoplePerHour.com) is a 'Digital HelpDesk in the Cloud', allowing clients to outsource and manage high volumes of small tasks, super fast, to a pool of curated experts.As part of the development team I had the chance to define the technical requirements of the project. We selected a combination of cutting edge technologies and development/managing patterns:- Agile Methodology, Kanban and Trello for team management to succeed continuous delivery- Mocha test Framework for our Test driven development with 100% test coverage (PHPUnit, API, Behavioral testing)- AngularJS Framework for the Frontend (ng-boilerplate, ui-router, custom authentication module)- Twitter Bootstrap v3 for the mobile friendly Design - MongoDB for storage (Repository pattern)- MySQL for the critical data (Repository pattern)- hand-coded API written in PHP Yii Framework- Docker and AWS for the distributed Web application components- Apostle.io for managing and sending emails- Google Tag Manager to manage tracking on several services (Google analytics, KISSmetrics)I was involved on all of the above technologies with emphasis on Frontend related goals.

Athens, Greece

As part of the ongoing improvement of PeoplePerHour site I managed or worked on many projects.Highlights:- upgrade to Twitter Bootstrap v3- upgrade to PHP Yii framework- creation of authentication and authorization mechanism, using both internal processes and external services like Facebook, LinkedIn, Twitter and Google account- optimization of user flow- several optimization tasks including database optimization and caching mechanisms

Neo Irakleio, Greece

Athens, Greece

- Implementation of API/REST service and integration with external API services- PHP projects using PHP Yii MVC Framework- Creation of eCommerce sites- Creation of Facebook applications and other promotional apps to drive traffic and accomplish client's objectives- Research in specific markets, analyze requirements, create of use case scenarios and offer a complete proposal with tech specifications- Advertising campaigns on Google AdWords and Facebook Ads

Athens, Greece

Pallini, Greece

Web developer and Project Manager. Frontend development with extensive usage of HTML5, CSS 3, Jquery and Ajax. Backend development using PHP framework, MySQL.

Web developer. Frontend development with extensive usage of HTML5, CSS 3, Jquery and Ajax. Backend development using Microsoft C# and other .NET technologies.

Masters, Programming And Network-Based Systems

Bachelor Of Science (B.S.), Computer And Information Sciences, General