Tobias Schreiber Senior Java Developer
Frankfurt, Germany • javadev@gmail.com • +49 69 5550 1488
Profile Summary
- Senior Java Developer with 9 years of experience building enterprise Java microservices at scale across wholesale banking, payments, and regulated SaaS, specializing in Spring Boot microservices, JPA tuning, and event-driven Kafka architectures.
- Hands-on coverage across Java LTS (Java 21), Spring ecosystem (Spring Boot 3), persistence (JPA with Hibernate, PostgreSQL), messaging (Kafka), and containers (Kubernetes, AWS) with strong fundamentals in strong OOP, generics, and concurrency fundamentals with a working command of virtual threads and reactive Reactor.
- Deep expertise in domain-driven microservice architecture, event-driven Kafka design, JPA modelling and query tuning, and cloud-native Kubernetes delivery, applying methodologies such as hexagonal architecture with strict bounded contexts and JVM tuning, GC profiling, and virtual-thread adoption under Project Loom to deliver reliable, high-throughput Java services fit for regulated enterprise scale.
- Engaged collaborator working cross-functionally with Product, Risk, SRE, and Platform teams in SAFe and Scrum delivery environments, contributing to architecture forums, sprint planning, and design reviews with an ownership-first mindset and clean handoffs.
- Mentor who shares technical excellence and fosters a culture of service reliability and secure-coding discipline through PR reviews and pattern docs, while running Java guild and architecture review sessions and authoring widely used service and persistence templates.
Technical Skills
- Languages & JVM:
- Java 21, Java 17, Java 11, Kotlin, Groovy (basic), records, sealed classes, pattern matching, virtual threads, streams, lambdas
- Spring Ecosystem:
- Spring Boot 3, Spring Framework, Spring Data, Spring Security, Spring Cloud, Spring Cloud Stream, Spring WebFlux, Actuator
- APIs & Microservices:
- REST, OpenAPI / Swagger, Jackson, Bean Validation, gRPC, GraphQL, Feign, Resilience4j, service discovery
- Persistence & Data:
- JPA, Hibernate, Spring Data JPA, MyBatis, JDBC, PostgreSQL, MySQL, Oracle, Flyway, Liquibase, query tuning
- Messaging & Events:
- Kafka, RabbitMQ, ActiveMQ, JMS, Spring Cloud Stream, Avro, Schema Registry, Kafka Streams
- Build, Test & Quality:
- Maven, Gradle, JUnit 5, Mockito, AssertJ, Testcontainers, WireMock, REST Assured, SonarQube, JaCoCo
- Cloud, Containers & CI/CD:
- Docker, Kubernetes, Helm, AWS (EKS, RDS, MSK), GitHub Actions, Jenkins, ArgoCD, GraalVM native images
- Security & Observability:
- Spring Security, OAuth2, OIDC, JWT, OWASP Top 10, Vault, Micrometer, Prometheus, Grafana, OpenTelemetry, ELK
Education
TU Darmstadt
M.Sc. in Computer
Science
Work Experience
Deutsche Bank
Senior Java
Developer
- Owned core Java service development and end-to-end delivery on the wholesale-banking post-trade settlement platform handling 3.2M trades / day, shipping trade capture, settlement workflows, and regulatory reporting across 18 modular Spring Boot microservices on modern Java LTS.
- Built service skeletons on Spring Boot 3 with Spring Framework, Spring Data, Spring Cloud, and Actuator, leaning on auto-configuration and bean DI plus AOP for cross-cutting concerns across 18 Spring Boot services, cutting boilerplate per service by 42%.
- Designed REST microservice contracts with versioned REST with OpenAPI contracts, Jackson serializers, Bean Validation, and Resilience4j for circuit breakers and retries across 120+ endpoints, pulling p95 latency from 640ms down to 180ms on the hot settlement path.
- Tuned persistence and data access through JPA with Hibernate, Spring Data repositories, Flyway migrations, and Hibernate criteria with second-level cache against a PostgreSQL cluster with 240+ tables, dropping slow-query incidents per release by 68%.
- Drove concurrency and JVM tuning with virtual threads under Project Loom, java.util.concurrent primitives, async profiler, and G1 GC tuning, lifting settlement throughput from 14k/min to 46k/min while trimming heap footprint per pod by 34%.
- Owned messaging and event-driven workflows on Kafka with Spring Cloud Stream, schema-registry Avro contracts, and Kafka event sourcing with idempotent consumers across 22 production topics, sustaining peak load of 180k msg/s with zero duplicate-settlement incidents over the last four quarters.
- Shipped cloud-native deployments with GraalVM native images on Kubernetes, Helm charts, ArgoCD GitOps, and 12-factor configuration on Kubernetes running 18 services with daily production releases, cutting cold-start time on critical services by 72%.
SAP
Java
Developer
- Owned build tooling and project management with Maven multi-module reactor builds, Nexus artifact hosting, dependency-convergence enforcement, and Jenkins pipelines across 14 modules in a shared enterprise SaaS monorepo, cutting full-build wall-time by 55% through cache reuse and parallel module execution.
- Drove testing and quality with JUnit 5 with Testcontainers, Mockito, AssertJ, WireMock, and REST Assured for integration coverage, plus Spring Boot Test slices for fast feedback, lifting line coverage from 48% to 86% and cutting regression-escape incidents per release by 58%.
- Hardened authentication and secure coding with Spring Security with OAuth2 and OIDC, JWT bearer tokens, secret rotation via Vault, and OWASP Top 10 review gates across 80+ secured endpoints, dropping audit-cycle OWASP findings on the SaaS tenant module by 74%.
- Strengthened core Java foundations across the team through records, sealed types, and stream pipelines, generics-heavy API design, and immutability-first refactors, while mentoring 4 junior Java developers through pair-programming, code-review checklists, and a written modern-Java idiom guide adopted across two squads.
