Backend developer · SAP · Java · Python · ABAP

I work at SAP SE on FI-CA and Convergent Invoicing in S/4HANA, building and maintaining backend services across public and private cloud environments. My work spans ABAP Cloud, Java/Spring Boot, and Python — from enterprise financial systems to data tooling and CLI utilities.

Before software I spent nearly two decades connected to professional theatre — first in ticketing operations, then as a playwright. That background shows up in how I approach domain modelling and user-facing tools.

📍 Sandhausen · Rhein-Neckar-Kreis · Germany   ·   SAP Certified Back-End Developer — ABAP Cloud

Java 21 · Spring Boot 3   Spring WebFlux · Spring Data JPA   PostgreSQL · Flyway   WireMock · JUnit 5   Python · Streamlit   Go   ABAP Cloud · OData V4   Docker · Hetzner

An Anti-Corruption Layer between SAP FI-CA and Convergent Invoicing, consuming OData V4 APIs via Spring WebFlux. Includes a full persistence layer (Spring Data JPA + Flyway), MapStruct mappings, and WireMock-based contract tests.

Spring WebFlux OData V4 WireMock MapStruct SAP FI-CA

A ticket sales analytics dashboard for a nonprofit theatre company, integrating Ticket Tailor and PayPal APIs. Covers yield analysis, repeat buyer retention, multi-night breakdowns, and financial reconciliation with PDF export. Deployed on Streamlit Community Cloud behind login-gated access.

Streamlit REST APIs OAuth2 Plotly live deployment

A Go service reconciling ticket sales against payment processor records for a nonprofit theatre company, ingesting Ticket Tailor and PayPal webhooks in real time with a REST-based backfill path for historical data. Deduplicates on the underlying transaction, flags transferred tickets and orphaned payments, and handles money as decimal/minor-unit values to avoid float rounding errors. Deployed via Docker Compose with a read-only query API enforced at the database role level.

Go PostgreSQL Webhooks OpenTelemetry Docker