Lead Software Developer at Vama

Led end-to-end backend development for a highly scalable chat backend, achieving sub-50 ms response times. Designed and implemented a microservice-based architecture with a focus on scalability, resilience, and maintainability. Managed the full lifecycle from architectural design to CI/CD, deployment, and production monitoring. Refactored the codebase to reduce size, improve modularity, and simplify migration to gRPC. Migrated infrastructure from VMs to Kubernetes with full automation via Terraform and ArgoCD, enabling unlimited environments with a single command. Built and maintained CI/CD pipelines with GitLab CI/CD and ArgoCD, deployed self-hosted Grafana for observability, and performed in-depth profiling to resolve bottlenecks. Addressed asynchronous and eventual-consistency challenges in a distributed backend. Implemented an MCP server to connect the backend API with an LLM, adding AI-powered chat capabilities.

Lead Software Developer at ESProfiler

Designed and delivered a multi-tenant Authorization Server with OAuth2 support, including federated OAuth2 and SAML. Built MVP with Spring Boot, OAuth2/OpenAPI tooling, and security auditing. Implemented an Integration Engine based on the runners concept, enabling user-run code inside a user environment via server (Java Spring Boot, MySQL) and a runner (Java, GraalVM) connected through WebSocket. Ensured proxy-enabled, secure WebSocket connections, editor API, encrypted script transfer, scheduled execution, and horizontally scalable runners. Technologies used included Java 7/8, Spring Boot, Lombok, Liquibase, JUnit, Testcontainers, Maven, OAuth2, MySQL, Docker, AWS, and OpenAPI.

Senior Software Developer at VID

Developed a new reactive backend for a social media application to replace an older async backend based on Javalin and CompletableFuture. Built a Java 11-based stack with Spring WebFlux, covering feature development, bug fixes, unit and E2E tests, and cloud configuration. Implemented CI/CD using AWS CodePipeline with Fargate and conducted code reviews to maintain high quality.

Senior Software Developer at Service - Flow Corp

Developed and maintained multiple microservices for the https://oneio.cloud product. Part of a shift from legacy to modern microservices, including two new services from scratch using Java 8, Kotlin, and Spring WebFlux. Contributed to frontend development with AngularJS, implemented unit and E2E tests, and conducted code reviews. Prototyped and delivered new frontend and backend services: Kotlin and Java 11 with Reactor, Angular 11, and related tooling (Feign, JUnit, Maven, Docker, Kubernetes, AWS). Also explored Kotlin-based microservices and other technologies (Ktor, GraalVM) as part of evaluation.

Senior Software Developer at T-Systems CIS

Designed and developed a web application for maintenance of communication stations. Server-side implemented with Groovy/Grails, and client-side with AngularJS 1.6 and TypeScript. Responsibilities included feature development, unit and E2E testing, architecture design, CI automation with Jenkins, and ELK stack configuration. Also involved in candidate interviews and mentoring as part of team growth.

Software Developer at Technoserv

Contributed to multiple projects, including Cloud Billing microservice architecture and a brand-new admin panel for paketchef.de. Tech stack encompassed Java 8, Spring Boot, Vue.js, MongoDB, Redis, KeyCloak, KillBill, Swagger, REST, Maven, Docker, Jenkins, Kubernetes, AWS. Also worked on migrating and replacing legacy frontend and backend with new microservices implemented from scratch in Java/Kotlin.

Software Developer at MW - Development

Developed web applications in C# for Microsoft Dynamics CRM customization and SharePoint integration. Worked on data proxying between services, and broader business-automation web apps using JavaScript/TypeScript on frontend and Spring-based backend components.

Software Engineer at Ecoterm

Developed a Java-based web-service, leveraging Spring, Maven, JDBC, and MySQL to deliver data access and integration functionality.