Saga Pattern Experts in Germany

• Fully on-premises LLM document-examination platform for a compliance-critical banking domain: agentic LangGraph pipeline with deterministic verification, every AI judgment structured and source-anchored; ~960 automated tests, zero data egress
• GPU throughput engineering (quantized serving, speculative decoding, prefix caching): 9.5x extraction speed-up, 500+ multi-document case files per day on a single A100
• AI-native EDI/EDIFACT integration platform (~116k LOC Java 25 / Spring Boot 4, 1,900+ tests): LLM-drafted partner mappings machine-verified before go-live (DFDL conformance, field-coverage checks, dry runs), ~99.5% byte match on real customer files — replacing weeks of manual mapping per partner

With project PRIZMA, DB will modernize its infrastructure on the one hand, and develop a fail-safe IT landscape on the other hand, which can be restored quickly and securely in case of a disaster.

• Capture current architectures of existing systems as well as methodical consulting and development of target architectures
• Deepen and maintain the building plan / target IT landscape
• Implement technical architecture concepts & architecture descriptions
• Implement migration concepts for updating and further developing the platform and information systems
• Assess submitted improvement suggestions as part of the project
• Capability management: identify capability gaps, develop target visions, and support transformation planning within the enterprise architecture.
• Create a compatibility matrix of the components in use and compare dependencies of specific versions
• Create an IT concept for extending the platform with the following topics: hardware and software requirements, security, licensing, high availability, load balancing, backup & recovery, update strategy, monitoring integration, etc.
• Coordinate with business architects as well as technical architects from the cross-functional architecture area of the PRISMA program for the topics (backup, Active Directory, monitoring, Citrix, and business applications ...)
• Status meetings and alignment of project planning with the Release Train Engineer / Project Manager
• Advise the Release Train Engineer / Project Manager in identifying project risks
• Advise the System Architect Engineers in steering the implementation of the concept
• Implement the IT concept
• Document the infrastructure

Label: MS Project, LINUX, Windows, ORACLE, Java, REST, SharePoint, Microsoft Exchange, UML, Enterprise Architect, BPMN, AZURE, AWS, V-MODEL, Micro Service, VisualStudio, SAP S/4HANA, SCRUM(SAFE), ESB (TIBCO), Python, Innovator, LeanIX (TOGAF), Ansible, Ansible Tower, Ansible Automation, ROBOT, SpringBoot

Transmission system operator – network provisioning platform (team lead)

• Designed the saga orchestrator in Python that provisions network fabrics with rollback.
• Split IP, identity, and resource allocation into bounded contexts with their own databases and typed clients.
• Implemented data access using DDD repositories and units of work, with no SQL in the domain code.
• Required integration tests using real PostgreSQL and RabbitMQ containers, and API fuzzing for every service.
• Introduced an agent workflow where a spec starts each change and a human approves every merge.
• Rolled out OpenTelemetry auto-instrumentation through GitOps across eighteen Kubernetes clusters.
• Led incident response for stuck provisioning and recorded every outage as a post-mortem.

Languages and software used: Python, FastAPI, Pydantic v2, SQLAlchemy async, PostgreSQL, RabbitMQ, Celery, pytest, testcontainers, schemathesis, Helm, Flux CD, GitLab CI, OpenTelemetry, pi coding agent.

Software product company – datacenter simulation SaaS (backend development)

• Built the asynchronous simulation pipeline as the second-largest contributor among more than twenty team members.
• Tagged every image by commit SHA and semver in the GitHub Actions deployment workflows.
• Diagnosed the RabbitMQ memory alarm that froze every simulation and fixed the limits in the Helm chart.
• Converted the test suite to function-style pytest, with coverage reported in every pipeline.

Languages and software used: Python, FastAPI, SQLAlchemy, Alembic, Celery, RabbitMQ, Redis, PostgreSQL, S3, EKS, Helm, Keycloak, GitHub Actions, pytest, mypy, ruff, SonarQube.

Internal AI platform – model serving and telemetry

• Built the FastAPI service that deploys open-weight models on GPU tiers as OpenAI-compatible endpoints.
• Upgraded production EKS by two Kubernetes minor versions and fixed zone-bound storage faults.
• Traced every model call, including its token count, cost, and latency, through the OpenTelemetry operator.

Languages and software used: Python, FastAPI, vLLM, LangGraph, pydantic-ai, OpenAI and Anthropic APIs, EKS, Helm, Flux CD, Terraform, GitLab CI, OpenTelemetry, Grafana.

• PHP legacy and Symfony 5+ development of N.V.L. Group's own ERP from PHP 7.4 onward including Oracle SQL, RabbitMQ, React and ExtJS
• Use of Docker and GitLab to manage containers and source code
• Implementation of unit, integration and functional tests
• Frontend development with React and ExtJS in Docker containers via GitLab

Zerobits is my vehicle for AI-powered automation and custom software development with a clear principle: AI solutions that reach production, not pilot stage. I design and build the systems myself - from first concept and architecture through implementation to deployment and operations.

My focus is on replacing repetitive, manual work with reliable automation and connecting disconnected tools and data sources into one dependable overall system.

Selected work:

• Design and implementation of LLM-based agent systems and RAG pipelines (Anthropic Claude, Mistral, MongoDB Atlas Vector Search + RAG)
• Workflow orchestration for long-running, fault-tolerant business processes using Temporal (temporal.io): saga patterns, event-driven architecture, retry and compensation logic, connecting third-party APIs and internal services into automated end-to-end processes
• Full stack product development: SaaS architecture on Kubernetes, TypeScript/React/NestJS, admin tooling with refine.dev and MUI
• AI-assisted development workflow as standard practice to deliver production software at a fraction of traditional timelines
• Full stack product development: multi-tenant SaaS architecture running on Kubernetes, backend with NestJS/Node.js and Python, frontend with TypeScript, React and Next.js, admin tooling with refine.dev and MUI, CI/CD with GitHub Actions

One of these projects is a product I own and operate - free of any NDA restrictions. I'm happy to demonstrate it end to end.

• Lead Product Owner for 4 development teams
• Leading and coordinating a greenfield project with parallel implementation of core components by independent teams; managing dependencies and resources
• Establishing a data lakehouse approach, including analysis of data volumes and future requirements as part of a cloud migration (best-of-breed approach)
• Responsible for requirements analysis, selection, and piloting of a LIMS/ELN system, supported by advising decision-makers and managing external vendors
• Introducing and managing an OpenWeb UI and Azure OpenAI-based RAG system to support knowledge extraction and data-driven analyses
• Setting up, configuring, and managing Jira projects, as well as developing project-specific workflows and automations
• Implementing classic Scrum processes with all ceremonies and taking on the Scrum Master role for all involved teams
• Assisting in hiring through interviews and assessments from a product owner's perspective
• Making key architectural decisions, including selecting the platform for the data lakehouse (Databricks) and the strategic integration of LIMS and analytics platforms

• Devised a new Domain-Driven Design architecture for a core system: reverse-engineered a central component, refactored the data-access layer to minimise database round-trips (improving scalability) and migrated processing to async.
• Decomposed the platform into independent .NET Core microservices (database-per-service) with RabbitMQ pub/sub using the Outbox Pattern + Saga choreography, behind an Ocelot API Gateway (JWT, rate limiting, CORS, health checks).
• Delivered on .NET Core / Angular / SQL Server / EF Core with Docker and Azure DevOps CI/CD; implemented health checks and CORS; contributes technical designs for stories in agile Scrum.
• Sole ADR owner; mentored 3 engineers and presented architecture decisions directly to the Director of Corporate IT.

• Led development activities for enterprise applications, managing design, planning, and delivery to meet organizational goals.
• Constructed and deployed microservices using Java/JavaEE, Kotlin, Spring Boot, Kafka incorporating synchronous and asynchronous communication, achieving a 95% on-time delivery rate.
• Developed microservices in Golang utilizing frameworks such as Gin, GORM, and Viper for high-performance applications.
• Maintained RESTful and GraphQL APIs, enabling seamless integration with enterprise applications.
• Leveraged gRPC for secure, efficient service-to-service communication in microservices, reducing latency.
• Used SQL databases (MySQL, PostgreSQL) and NoSQL databases (MongoDB, Redis).
• Integrated publisher-subscriber systems and message queue architectures (SQS, Kafka).
• Configured secure authentication and authorization systems (OAuth 2.0, OpenID Connect) using AWS Cognito and Spring Security.
• Architected scalable patterns like API Gateway, Circuit Breaker, Saga, CQRS, and Event Sourcing to enhance reliability and performance.
• Built middleware solutions integrating complex APIs and third-party services for seamless system interactions.
• Achieved cloud-native architectures with AWS services, including S3, EC2, Lambda, API Gateway, RDS, DynamoDB, SNS, SQS, EKS, ECR, and ECS.
• Delivered a centralized CI/CD pipeline, reducing deployment time by 80% through automation and standardization.
• Integrated observability tools such as Prometheus, Grafana, Datadog, and CloudWatch, improving monitoring and troubleshooting capabilities.
• Automated IaC provisioning with Terraform, ensuring consistent and scalable environments across development, testing, and production.
• Enhanced logging and visualization using the ELK stack (Elasticsearch, Logstash, Kibana).
• Optimized release processes, ensuring efficient and error-free deployments, resulting in a 30% reduction in production bugs.
• Lifted services to the cloud, transitioning legacy systems to a cloud environment to improve scalability and performance.
• Automated infrastructure tasks with Python, streamlining workflows such as S3 file uploads and SQS event handling.
• Crafted Python scripts to test AWS services locally using LocalStack, achieving 98% accuracy.
• Designed and architected large-scale, scalable enterprise applications, performing end-to-end, unit, and integration testing, reducing production bugs by 25%.
• Designed and developed web applications using Angular, HTML, CSS, and JavaScript.
• Integrated advanced security measures into the DevSecOps pipeline, including SAST with SonarQube, DAST using OWASP ZAP, vulnerability scanning with Snyk, container image scanning via Trivy.
• Mentored 5+ junior developers in Java, Kotlin, and microservices, boosting team productivity by 20% within six months.
• Facilitated workshops on modern architecture, DevOps, and cloud integration practices, enhancing team proficiency.