Theofilos Chamalis
Senior Full Stack Developer & Team Lead
Building web, mobile, and AI-powered products for teams that need to ship.
A short introduction
I am a senior full stack developer and team lead from Serres, Greece, currently based in Thessaloniki. I hold an M.Sc. in Computer Science & Engineering (Data Mining thesis) and a Bachelor's degree in Mathematics, both from the University of Ioannina.
I have been building software for more than 10 years, across freelance work, my own company (Evolvium / EVO PTT), and product teams at VieConnect, Crowdlinker, EF Education First, and now Vee. Most of my day-to-day work sits in TypeScript: React and Next.js on the frontend, Node.js and NestJS on the backend, plus React Native when a mobile app is part of the product.
Lately I spend a lot of time on cloud-native infrastructure (AWS and GCP) and AI agent integrations. I care about shipping things that hold up in production, and about designing interfaces that people actually enjoy using.
Tools I use regularly
React.js
Next.js
Vue.js | Tailwind
React Native
Ionic React
Java | Android
Node.js
NestJS
GraphQL | REST
TypeScript
JavaScript
Java | SQL
MongoDB
PostgreSQL
DynamoDB | MySQL
AWS
Google Cloud
Serverless
Docker | K8s
Terraform
CI/CD | ArgoCD
OpenAI API
LangChain
LangGraph
Figma
Photoshop
Illustrator
Where I have been working
Promoted to Team Lead in January 2025 to lead development of the Donna AI agent, managing and mentoring a team of 3 developers while owning the core architecture.
I designed the product infrastructure and end-to-end flows, including event-driven microservices and a Next.js frontend that plugs into the main platform. Infrastructure runs on Google Cloud (GKE) with ArgoCD and Terraform. I also worked on the Maggie AI agent using Next.js, React, Node.js, NestJS, and GraphQL.
I founded Evolvium and built EVO PTT (evoptt.com), a VoIP push-to-talk product used daily by professional teams. The company grew to serve enterprise clients including TITAN Group, Jio Mobile, and the Department of Security (Thailand).
In 2023 I moved the business to a self-managed operational model and kept high-level technical and strategic oversight while focusing on other full-time roles.
Built web applications used globally by over 500,000 users with Next.js, React, TypeScript, and Tailwind CSS. On the rebranded multi-market Destination Pages we improved load times by 32%, page build times by 4x, and cut mean API latency by about 0.5 seconds.
I also worked on backend systems and cloud infrastructure with Node.js, NX monorepos, AWS, and Terraform, and helped Marketing ship dynamic pages through Storyblok. The team was distributed across the US, UK, and India.
Built web and mobile apps for enterprise clients including MLSE (about +20% user engagement), Yumba (about +16% restaurant orders), and OmStars (about +25% user retention). Stack covered Next.js and React on the frontend, Node.js and AWS Serverless on the backend, and React Native for iOS and Android.
Led end-to-end development of the SECCO platform: a React web app, a React Native mobile app, an AWS Lambda serverless backend, and a Node.js metrics collector for Raspberry Pi devices deployed across 80+ nursing homes in France.
Promoted to Team Lead in June 2018. I hired and managed a team of 8 developers during the company's scale-up, and handled IT administration plus CI/CD (GitLab, Bitrise) for web, mobile, and backend projects.
During military service I was IT Administrator at the Klisaris Army Camp in Serres. I looked after the camp's computers, servers, and network: uptime, performance, and security.
Primarily Android development, with some web work, for about 4 months in Ioannina. I built the QR-PTT Push to Talk Android app and its WordPress site. QR-PTT is a PTT-over-IP client for teams that need constant communication on Android devices.
Teaching assistant for Computational Mathematics and Probabilities & Statistics in the Computer Science and Engineering Department.
Volunteered for 4 months on network security for the library's computers and Android tablets, plus day-to-day IT support for staff and visitors.
Studies and selected credentials
Major in Software Engineering, grade 9.36 / 10. Thesis on Data Mining, focused on clustering methods based on statistical testing of unimodality (K-Means family).
Degree 6.41 / 10, with a major in Computer Science and Algorithms (7.32).
Certificate of Competency in English (Proficiency) from the University of Michigan.
AWS Certified Cloud Practitioner, Amazon Web Services, earned June 2022.
NestJS: The Complete Developer's Guide, Udemy, January 2022.
Arc Certified Remote Developer, Arc.dev, February 2021.
Selected projects I can show publicly
Questions, roles, or project ideas: email or call works best.
Iakovou Polila 6, 54248, Thessaloniki, Greece
