Event Sourcing Experts in Berlin
, matched with vetted and available freelancersHire experts who design event-driven architectures, model business events, and connect Event Sourcing with CQRS, Kafka, or Axon Framework. FRATCH matches you quickly and precisely with vetted, available freelancers for complex software projects.
Meet FRATCH Experts in Berlin, who have recently used Event Sourcing
Aamir S.
Last position:
Founder at Self-Directed Project Work
- Building independent projects in the AI/developer tools space.
- Experimenting with product ideas, rapid prototyping, and go-to-market validation.
- Designing AI-native operating model—leveraging agentic pipelines, living context schemas, and rigorous eval harnesses to multiply individual contributor leverage and eliminate implementation bottlenecks.
Nikunjkumar P.
Last position:
Senior Java Backend Developer at Questax Professionals GmbH
- Provide the Price Listing Service team with prices for all cars and vans in different markets
- Adapt market-specific requirements such as taxes, government subsidies, campaigns
- Import and synchronize new prices for all new and existing cars and store them in the Redis datastore
- Support our product and on-call duty
- Daily business, development of new features, bug fixing
- Pair programming, code review, mob programming
- Develop POCs for new ideas
- Maintain and extend the backend
- DevOps tasks
- Run Kubernetes updates
- Adjust and further develop Kubernetes resources
- Develop and adapt Helm charts
- Adapt and update ArgoCD
- Maintain, adapt, and improve CI/CD
Jan H.
Last position:
Technical Co-Founder at Telemarie UG
- Technical leadership & SW architecture: Conducted trade-off analyses for technology stacks and led the design and implementation of the software architecture, including mobile and backend solutions. Facilitated Event Storming workshops for DDD and SW architecture.
- Strategic direction & organizational development: Played a key role in defining the strategic direction of the product and organization, exploring new forms such as ownership responsibility.
- Lean Startup & Agile development: Introduced Lean and Agile principles, implemented Lean prototypes, and ensured compliance with Lean Startup processes, iteratively moving from Product/Solution-Fit to Product/Market-Fit.
- Team building & collaboration: Facilitated workshops, retrospectives, and futurespectives to collaboratively develop tactics and strategies.
- Technologies: Flutter, JS/TS, React, Google Cloud, Firebase, Android, iOS.
- Organizational methods: Lean startup, lean canvas, lean agile, event storming, retrospectives.
Fady K.
Last position:
Senior Software Developer / Tech Lead at Specific Objects Technologies GmbH
- Project 1: Multi-Tenant SaaS Platform: Data Integration & Pricing Management
- Objective: New development of ELT pipeline (replacement for Java 6 legacy), integration of heterogeneous source systems (CSV, Excel, Email, external DBs), event-sourcing for complete auditability, multi-tenant architecture for tenant-capable data processing
- Challenge: Processing millions of records daily, audit compliance, data isolation between different tenants
- Solution: Stakeholder workshops for requirements analysis, event-driven architecture with Axon Framework and Apache Kafka, AWS services (EC2, S3, Lambda, SQS, API Gateway) for cloud integration, PostgreSQL with tenant-specific schemas for multi-tenant data isolation, REST API design with Spring Boot for external system integrations, comprehensive testing strategy (JUnit, Spring Test, Postman, PACT, ArchUnit)
- Results: ELT performance improved from 30+ min to 1-5 min; 2-3 hours daily saved through workflow automation; 10-20 hours/week saved through event-sourcing auditability; 100% audit compliance; secure multi-tenant data isolation for 10+ tenants
- Project 2: Multi-tenant CRM System Modernization
- Objective: Migration of CRM system (20+ years PHP/MySQL) to Java microservices, Domain-Driven Design implementation, establishment of Test-Driven Development, multi-tenant-capable SaaS architecture for multiple customer tenants
- Challenge: Remodeling complex business logic, no existing test culture, scalable tenant management with data isolation
- Solution: Comprehensive testing strategy (JUnit, Spring Test, Postman, PACT, ArchUnit), multi-tenant architecture with tenant-specific databases, REST API design with Spring Boot for cross-tenant integration, Kubernetes and Docker for container orchestration
- Results: 2× performance improvement; deployment time reduced from 40+ min to 5-7 min; migration without production outages; scalable multi-tenant solution for 15+ customer tenants
- Technologies: Java, Spring Boot 3.x, Angular, Apache Kafka, AWS (EC2, S3, Lambda, SQS, API Gateway), PostgreSQL, Axon Framework, Kubernetes, Docker, GitLab CI, REST API
Martin M.
Last position:
Florio C3G
- App that helps patients schedule their medication, track their symptoms, and biomarkers
- The app is being certified as a medical device
- Technologies: React Native, Expo, Redux Toolkit
Michael W.
Last position:
TUI AG / Robinson
- Development of an Internet Booking Engine IBE (Saber and Juniper) and other microservices
- Backend development with PHP and Symfony, endpoint and interface implementation
- Unit and integration testing
Mario E.
Last position:
Developer and Consultant at Freelancer
Discover over 15,000 top freelancers
Statistics of experts using Event Sourcing
Aggregated from the professional profiles of matched freelancers.
Experience
25 years
Position duration
3.1 years
Positions per freelancer
12
Top business areas
Information Technology, Product Development, Project Management
Top industries
Information Technology, Retail, Education
Certification focus areas
Information Technology, Product Development, Project Management
Bachelor's degree or higher
100%
Master's degree or higher
80%
Certifications per freelancer
1
Most common languages
English, German, Spanish
Speak two or more languages
100%
Based on our profile pool as of 29 Oct 2026.
Daily rate distribution
The chart shows how the daily rates of experts in this technology in Berlin are distributed, based on recent contracts on our platform. Each bar covers a rate range — its height shows the share of experts charging within that range.
Average rates of experts in Berlin using Event Sourcing
Rates are based on recent contracts and do not include FRATCH margin.
The average daily rate is the mean of all daily rates from recent contracts of comparable freelancers on our platform.
The median daily rate is the middle value of all daily rates — half of comparable freelancers charge less, half charge more. Unlike the average, it is barely affected by outliers.
Calculated based on our freelancers’ daily rates as of 29 Oct 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
Event Sourcing experts industry focus
See which industries our matched freelancers work in most often — every figure is calculated live from the freelancers on FRATCH.
- Information Technology (100%)
- Retail (71%)
- Education (57%)
- Automotive (43%)
- Fashion (43%)
- Insurance (43%)
- Media and Entertainment (43%)
- Telecommunication (43%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
Core principle
Event Sourcing stores state changes as an ordered history of business events instead of keeping only the latest value. Applications rebuild current state by replaying that history, creating an auditable record of what happened and when. This approach supports traceability, temporal queries, and reliable domain workflows.
What it builds
Event Sourcing fits systems where business decisions depend on a complete history of actions and transitions.
- Financial ledgers and payment workflows
- Order, inventory, and fulfilment systems
- Claims, subscriptions, and account lifecycles
- Auditable workflows for regulated operations
Architecture and tooling
Professionals combine Event Sourcing with domain-driven design, event-driven architecture, and often CQRS. Common ecosystem choices include Apache Kafka, Axon Framework, EventStoreDB, Marten, Kafka Streams, and cloud-native messaging services. The right design separates event storage, command handling, projections, and integration concerns.
When expertise matters
Companies usually bring in freelance specialists when an existing system needs an auditable history, when distributed workflows are becoming difficult to reason about, or when projections and integrations have grown unreliable. They may also need help migrating from CRUD services without losing business data or operational continuity.
- Define stable event names and schemas
- Design aggregates, commands, and projections
- Plan replay, correction, and migration strategies
- Establish observability and operational safeguards
Skills that set experts apart
Strong professionals understand that events are long-lived contracts, not temporary implementation details. They can identify meaningful domain events, control aggregate boundaries, handle idempotency, and explain the trade-offs between immediate consistency and eventual consistency. They also test replay behaviour and projection recovery under realistic failure conditions.
Delivery and collaboration
Event Sourcing affects product rules, data ownership, operations, and integration contracts, so successful delivery requires close work with product and domain specialists. Remote collaboration works well when event models, decision records, and system diagrams are kept clear and current. In Berlin, teams may also value professionals who can collaborate comfortably in English and, where needed, German.
Frequently asked questions
Everything clients usually want to know about Event Sourcing, in one place.
Event Sourcing is used to preserve a complete history of changes in a system. It is valuable for financial records, order lifecycles, permissions, claims, and other domains where teams must explain how the current state was reached.
Event Sourcing records business events rather than overwriting the current state in place. CRUD is often simpler for straightforward data management, while Event Sourcing offers stronger traceability but requires careful event modelling, projection management, and operational discipline.
Event Sourcing is a persistence approach in which events form the system’s source of truth. Event-driven architecture is broader and describes communication through events; a system can use event-driven integration without storing its state through Event Sourcing.
Event Sourcing work commonly requires domain-driven design, CQRS, messaging, distributed systems, and database design. Useful ecosystem experience may include Apache Kafka, Axon Framework, EventStoreDB, schema evolution, observability, and automated testing.
Event Sourcing does not require a large team, but it does require sound architectural judgement. A specialist should have handled event versioning, replay, idempotency, projection failures, and migration decisions in systems with meaningful business consequences.
Event Sourcing projects can be delivered remotely when teams document event contracts, domain decisions, and operational procedures clearly. Berlin-based companies should agree early on collaboration hours and whether English, German, or both are needed for workshops and stakeholder communication.
Event Sourcing expertise is shown through precise domain modelling and clear explanations of trade-offs, not through tool names alone. Ask how the professional handles event immutability, schema changes, duplicate messages, failed projections, replay safety, and data correction.
Event Sourcing may be a poor fit for simple applications where only the latest state matters and auditability has little value. It can add unnecessary complexity when the team cannot maintain event contracts, operate projections, or invest in the testing and monitoring the approach demands.
The average hourly rate of freelancers in Berlin, Germany who have used Event Sourcing in their recent projects is 97 €, which corresponds to a daily rate of about 779 € based on an 8-hour working day.
Of the freelancers in Berlin, Germany who have used Event Sourcing in their recent projects, 100% hold at least a Bachelor's degree and 80% hold at least a Master's degree.
On average, freelancers in Berlin, Germany who have used Event Sourcing in their recent projects have 25 years of professional experience, with a single engagement typically lasting around 3.1 years.
The most common languages among freelancers in Berlin, Germany who have used Event Sourcing in their recent projects are English (100%), German (86%), and Spanish (29%).
The most common industries among freelancers in Berlin, Germany who have used Event Sourcing in their recent projects are Information Technology (100%), Retail (71%), and Education (57%).
The most common business areas among freelancers in Berlin, Germany who have used Event Sourcing in their recent projects are Information Technology (100%), Product Development (100%), and Project Management (43%).
Main locations of FRATCH Experts, who have recently used Event Sourcing
Our freelancers and interim experts are at home across the DACH region — available on-site in the major business hubs or fully remote. Choose a location to discover matched specialists, local market insights and up-to-date availability.
Countries:
Berlin 
Hamburg Munich Cologne Frankfurt Stuttgart Dusseldorf Leipzig Dortmund Essen Bremen Dresden Hanover Nuremberg Request a free demo
Get in touch with the FRATCH team and we will get back to you within 4 hours.
Would you rather directly get in touch?
We always have the time for a call or email!
Philipp Thomaschewski
FRATCH CEO
