Engineering Transformation & Technical Turnaround | Legacy Modernisation | Software & Data Architecture | AI-Enabled Engineering

12/2023 – offen

Trading Surveillance Platform
Joined a successful but heavily legacy-constrained product at a point where its engineering practices and architecture were struggling to keep pace with business needs.

Took ownership of technical strategy and architecture for a trading-surveillance platform serving ~25 production clients. The platform performs deadline-critical end-of-day processing where data integrity, predictable completion and alert quality are essential.

With growing data volumes exposing fundamental scalability constraints, continued feature demand and substantial accumulated technical debt, a conventional rewrite was neither realistic nor particularly desirable. I progressively evolved the platform through a staged strangler-fig approach, allowing product delivery, production stabilisation and architectural modernisation to proceed in parallel.

Architecture & transformation

* Established the technical transformation roadmap and aligned its sequencing with the product roadmap, deliberately using architectural improvements as enablers for new product capabilities rather than competing with feature development for attention.
* Introduced greenfield Spring Boot services around the legacy platform. Personally established the architecture and initial implementations, then transferred development progressively to the team. These services now provide a cleaner path for client-facing development and developer onboarding.
* Established a new calculation platform for complex surveillance logic: designed its structure, implemented reference patterns and guided developers through subsequent implementations. New calculations can now be developed in a structured, testable and performant environment while existing legacy calculations are migrated progressively.
* Architected the ongoing data-platform transformation from MSSQL-heavy processing and storage towards ADLS/Parquet and Microsoft Fabric/Spark with a substantially smaller operational database footprint.
* Personally built the core Spark ETL and Java orchestration components and designed their integration into the existing processing flow. New processing stages preserve downstream legacy contracts, allowing individual parts of the pipeline to be replaced without requiring a high-risk end-to-end migration.
* Stabilised critical areas of the existing platform sufficiently to halt the previous pattern of repeated infrastructure upscaling and begin reducing hosting costs.
* Led systematic application-security hardening and introduced stronger automated engineering-quality controls.

Engineering & delivery

* Progressed from Senior Java Engineer to Engineering Manager while retaining hands-on ownership of critical architecture and implementation.
* Restored sustained roadmap delivery during a period of significant technical and organisational change, while running the modernisation programme in parallel.
* Rebuilt engineering capability through hiring, performance management, hands-on mentoring and intensive knowledge transfer.
* Established a working model of architecture → reference implementation → guided adoption → team ownership, enabling developers to progress from heavily supported implementation towards independent feature delivery and increasingly substantial technical design.
* Improved operational knowledge transfer and reduced reliance on development for routine deployment and production-support activities.

Current focus: progressive migration of calculations, rollout of the new data-processing architecture, further reduction of infrastructure constraints and continued movement of product development away from legacy dependencies.

Engineering Manager, Software Architecture, Teamleiter IT

1/2023 – 9/2023

Hands-on development and modernisation of an existing enterprise Java application. Refactoring, migration from Java 8 to Java 17, code review and improvement of maintainability and engineering quality.
Entwicklung, Refactoring, Java 8 - Java 17 Upgrade, Code Review

Code-Review, Java (allg.), Spring Framework

10/2022 – 11/2022

Short-term engagement during a time-critical delivery phase. Joined the team to increase senior engineering capacity and help bring the planned release to completion, contributing hands-on development, problem solving and code review.

Code-Review, Java (allg.), Spring Framework