Cloud Engineers in Berlin

AI Platform Backend – Senior Developer

Brought in to design and build a backend for an AI platform from scratch, including multi-provider LLM orchestration and real-time infrastructure for AI influencer personas at scale.

Tasks and responsibilities

• Architecture and implementation of a multi-LLM orchestration layer with Semantic Kernel to integrate GPT-4 and other providers for core platform logic and AI influencer personas, reducing model-switching overhead by abstracting provider APIs behind a single interface.
• Design and development of a backend from scratch in C# / .NET 10, including domain modeling with DDD, a versioned RESTful API layer, and cloud infrastructure setup on Azure.
• Built a real-time chat infrastructure with Server-Sent Events (SSE), message persistence, and delivery guarantees for live operation of AI influencer personas at scale.
• Developed a media management service with integration of cloud object storage for upload and retrieval of influencer-generated content.
• Created an integration and unit test suite with data seeding for reliable regression testing across all core platform flows, significantly reducing production error rates.

Tools and technologies: C#, .NET, ASP.NET Core, Python, TypeScript, MySQL, Semantic Kernel, EF Core, Minimal APIs, LLM Orchestration, Prompt Engineering, Agentic AI, Generative AI, AI-Assisted Engineering, Claude Code, GitHub Copilot, Google Gemini, OpenAI API, Ollama, Redis, Azure, Azure Container Apps, Azure Database for MySQL, Docker, GitHub Actions, Clean Architecture, Vertical Slice Architecture, CQRS, Domain-Driven Design, REST API, xUnit, Integration Testing, Unit Testing, Jira, Confluence, Scrum

• Independently designed, developed, published, and maintained mobile games for iOS and Android.
• Implemented application architecture, gameplay systems, UI, monetization, analytics, and platform integrations.
• Managed the complete release lifecycle, including testing, store publication, production monitoring, and iterative improvements based on analytics.

• Built and operate a hybrid Kubernetes platform across bare metal and cloud to validate multi-GPU workloads, security-zone isolation, and disaster recovery.
• Operate self-hosted AI coding agents in the platform's Git workflow, from issue triage to pull-request review; every change is gated by manifest diffs and policy checks in CI.
• Co-developed a sensor-fusion and GPU edge-inference platform selected by the European Defense Tech Hub from 50 solutions for field testing.

OpsWorker turns Kubernetes alerts into root-cause analyses, on top of the monitoring a team already runs. I lead the technical side: the agent architecture, the AWS infrastructure it runs on (fully inside EU regions), and the engineering decisions behind it, read-only in the cluster by default, human in the loop for judgment. The stack underneath: Amazon Bedrock and Bedrock AgentCore, agents built with the Strands Agents SDK, the Claude and OpenAI APIs, and the Kubernetes API.

• Lecturer for the GenAI Track at the Master School Institute of Technology
• Development of a full-stack AI application (React + Python/FastAPI) for automated supplier product import with intelligent column and category classification (4-layer hierarchical) including human-in-the-loop validation

• Context: Healthcare and laboratory teams required faster document analysis, treatment-planning support, and reliable AI workflows for MR/VR-assisted operations.
• Contribution: Built the AI healthcare platform, model/agent workflows, VR-glasses deployment platform, REST APIs, Next.js/React interfaces, and CI/CD pipelines.
• Impact: Delivered a production-ready AI product foundation that improved clinical document review, supported laboratory automation, and made VR fleet deployment manageable across environments.

Tech: TypeScript, Next.js, Node.js, React, Java, Spring Boot, Python, PyTorch, TensorFlow, Docker, PostgreSQL, OpenAPI, GitLab, GitHub Actions.

• Insurance service provider*

Challenge: Business-critical documents were processed through external OCR providers, with ongoing costs, dependency, and data privacy risks for sensitive insurance data.

Implementation:

• Architecture and production implementation of an on-premise OCR solution with full data ownership
• Methods for recognizing document structures as the basis for automated further processing
• ML-, NLP-, and LLM/VLM-based information extraction, especially from invoices and quotations

Success: Replaced external providers: full data ownership, GDPR-compliant processing, and 75% lower recurring OCR costs per year

Used technologies: Python, Docker, Microservices, FastAPI, PyTorch, Torchvision, MongoDB, MySQL

• Consulting an NGO in the field of data center sustainability in publicly funded projects (BMUKN with NADIKI and Umweltbundesamt with SIEC)
• Development of Python APIs and web applications, deployment on AWS/ECS with Terraform
• Collecting power consumption metrics for servers, CPUs, GPUs running AI workloads
• Technologies used: AWS, EC2, ECS, Fargate, CloudMap, VPC, Route53, Lambda, EventBridge, CodeBuild/CodePipeline/CodeDeploy, Terraform, Docker, Linux, Bash scripting, Python, Flask, SQLAlchemy, SQL, MariaDB, InfluxDB, Telegraf, Prometheus, Zabbix, Kubernetes, Letsencrypt, certificate management

Java 21 · Spring Boot 3 · Keycloak · PostgreSQL · Docker · Nginx · GitHub Actions · DigitalOcean · React 18 · TypeScript · Plasmo

• Architected and shipped a production-ready Job Application Tracker end-to-end: REST API with 5-stage workflow, pagination, sorting, and dynamic filtering — full ownership from design to live cloud deployment on DigitalOcean.
• Implemented production-grade identity management: OAuth 2.0 / OpenID Connect / JWT / RBAC via Keycloak, applying Hexagonal Architecture and DDD principles.
• Built automated CI/CD pipeline (GitHub Actions); containerised with Docker; Nginx reverse proxy with path-based routing and SSL termination.
• Developed a Chrome Extension (Plasmo framework, Manifest V3) that auto-fills job applications directly from LinkedIn into the tracker — demonstrates full product thinking across backend API and browser client.

• Supported the company's transition from an on-premise architecture to AWS cloud services, modernizing infrastructure and optimizing operational efficiency.
• Leveraged expertise in automation and software implementation to enhance scalability, reliability and profitability.
• Implemented Poetry and Ruff to streamline Python dependency management and code quality checks, improving development efficiency and reducing errors.
• Implemented an automated CI/CD strategy with GitHub Actions, which decreased deployment times and minimized manual intervention.
• Enforced deployment automation for Kubernetes, enhancing the scalability and reliability of applications across the organization.
• Evaluated and implemented Apache Airflow for workflow management, leading to more efficient scheduling and monitoring of data pipelines.
• Created data interfaces for energy traders, enabling them to optimize profit margins through improved data analysis and decision-making tools.

• Developing GitHub Actions/pipelines for automatic application deployment
• Supporting the provisioning of Helm charts for the CI/CD infrastructure
• Rebuilding and migrating a Kubernetes cluster using Rancher
• Creating IaC with Terraform for Kubernetes and additional services (monitoring, databases)
• Deploying a highly available Percona Galera cluster (MySQL)
• Implementing a centralized monitoring and logging infrastructure

• Refactored the mobile app by reimplementing stores, models, API client, screens and components using Typescript
• Added performant on-device storage for stores as preparation for offline mode
• Integrated RNUILib to achieve a minimal and modern UI design quickly
• Implemented native packages to provide additional features such as displaying of caller IDs
• Planned feature development and UX improvements following initial refactoring and redesign

• Provisioned a Kubernetes platform on Open Telekom Cloud CCE with comprehensive network isolation
• Built a VPC architecture with public, private, and data subnets
• Integrated managed services: RDS PostgreSQL, DCS Redis, DMS Apache Kafka
• Implemented monitoring with Cloud Eye and Log Tank Service

IMPACT: Cloud Infrastructure Engineer delivered a production-ready platform in 5 days with full network security isolation

• Development, operation and support of BI platforms and microservice architectures
• Development of an open-source BI scheduling tool