Available for part-time projects
Reliable backends and infrastructure.
I’m Thanos Polymeneas, a backend and infrastructure engineer with a background in mathematics and over 20 years of experience. Through KnG Development I build, host and maintain systems for clients.
Legacy modernization
Old PHP and Symfony projects brought up to date in small, tested steps, then containerized with a delivery pipeline built for each client.
PHP 5 to 8.5. Symfony 2 to 7.
Infrastructure and CI/CD
Servers managed as code, pipelines that fit your workflow and zero-downtime blue-green deployments. I also host and maintain client applications, WordPress sites and web shops.
Hetzner, AWS and GCP. Ansible, Terraform, Docker, GitHub Actions, GitLab. Secured with fail2ban, blocklists and firewalls, monitored with Grafana and Loki.
Backend architecture
Real-time APIs, messaging systems and internal platforms that scale with your business. At MessageBird I helped build a highly available, multi-region API for voice calls.
Go, PHP, Kubernetes, Elasticsearch, Prometheus. SIP, Kamailio, Asterisk.
AI-assisted development
AI agents are part of my daily work, from agentic workflows that carry out multi-step tasks to everyday coding, review and debugging. Tests and careful review keep the results under control.
At MessageBird I introduced the automated testing flow that made full automation through an AI-powered CI/CD system possible.
Billancer
My own app, live on the App Store for macOS and iOS. I build and run it myself, including the full release process through TestFlight and App Store Connect.
Experience
I care about happy and productive teams, maintainable software and automating workflows.
- 2024–now
KnG Development Founder
Backends, hosting and legacy upgrades for clients, and my own app, Billancer.
- 2018–2024
MessageBird Senior software engineer
Multi-region real-time voice API, automated testing and AI-powered CI/CD.
- 2016–2018
Endouble Team lead
Led three senior developers building a PaaS framework for recruitment websites.
- 2015
Werkspot Senior web developer
Built the international platform on Symfony and rolled it out to its first new country.
- 2014
Symbid Senior backend developer
Built a new financial SaaS product.
- 2009–2013
Webclusive Full-stack developer
Custom websites in WordPress, Zend Framework and Symfony, and a rostering system for a bakery chain.
- 2003–2010
Freelance, Athens Full-stack developer
CMS development in PHP and Perl, where my interest in clean code began.
On the disc, each ring is a year, from 2003 at the centre to today at the edge. The bright rings mark the start of each role.
Mathematics
I studied pure and applied mathematics before computer science. It still shapes how I work: careful reasoning, clear models and simple solutions.
The disc on this page follows Vogel’s sunflower model: each pillar turns by the golden angle from the last. Here it draws Hilbert’s curve: each pass folds one line into a grid twice as fine, and in the limit that single line fills the whole square.
- 2007
MSc Computer Systems Technology
Kapodistrian University of Athens
- 2004
BSc Pure and Applied Mathematics
Kapodistrian University of Athens
Get in touch
Available for part-time freelance projects and technical consulting. Based in Purmerend, near Amsterdam. I work in English and Greek, and understand Dutch and Portuguese.