CQRS Experts in Berlin
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Meet FRATCH Experts in Berlin, who have recently used CQRS
Jorge N.
Last position:
Senior Developer at NDA
AI Platform Backend – Senior Developer
Hired to design and build an AI platform backend from the ground up, including multi-provider LLM orchestration and real-time infrastructure for AI influencer personas at scale.
Tasks and Responsibilities
- Architected and implemented a multi-LLM orchestration layer with Semantic Kernel to integrate GPT-4 and other providers for core platform logic and AI influencer personas, reducing model-switching overhead by abstracting provider APIs behind a unified interface.
- Designed and developed a backend from the ground up in C# / .NET 10, including domain modeling with DDD, a versioned RESTful API layer, and cloud infrastructure on Azure.
- Built real-time chat infrastructure with Server-Sent Events (SSE), message persistence, and delivery guarantees for running AI influencer personas live at scale.
- Developed a media management service with cloud object storage integration for uploading and retrieving influencer-generated content.
- Created an integration and unit test suite with data seeding for reliable regression testing across all core platform flows, significantly reducing the production error rate.
Tools and Technologies: C#, .NET, ASP.NET Core, Python, TypeScript, MySQL, Semantic Kernel, EF Core, Minimal APIs, LLM Orchestration, Prompt Engineering, Agentic AI, Generative AI, AI-Assisted Engineering, Claude Code, GitHub Copilot, Google Gemini, OpenAI API, Ollama, Redis, Azure, Azure Container Apps, Azure Database for MySQL, Docker, GitHub Actions, Clean Architecture, Vertical Slice Architecture, CQRS, Domain-Driven Design, REST API, xUnit, Integration Testing, Unit Testing, Jira, Confluence, Scrum
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
Khaled M.
Last position:
Senior/Staff Backend Engineer at Heycar (Mobility Trader GmbH)
- Heycar is a leading automotive platform redefining the used car market through intelligent data pipelines, multi-tenant services, and dealer-focused tooling. I led initiatives across backend architecture, data ingestion, and identity management to enhance scalability, reliability, and developer productivity.
- Ingestion Platform: Designed a unified ingestion platform with YAML-based configuration, enabling new dealer data pipelines to be onboarded without code changes, cutting setup time from ~2 months to 2-3 days and improving scalability by 40%.
- Keycloak Leadership: Acted as the company's Keycloak expert, scaling it for multi-tenant identity management and extending functionality with custom plugins and delegated admin APIs.
- Back-Office Tooling: Developed a back-office application integrated with Salesforce, enabling dealers to manage inventory, convert leads, and handle support requests in real time.
- Multi-Tenant Migration: Collaborated across backend teams to migrate Heycar's core services into a unified multi-tenant cluster, ensuring high availability.
- Frontend CI Optimization: Optimized monorepo delivery by implementing CircleCI dynamic config with NX, deploying only affected UI projects and drastically cutting build times.
- Observability & Mentorship: Enhanced monitoring and release reliability while mentoring backend engineers and improving code review standards.
Muhammad A.
Last position:
Senior Software Engineer at Verbund Pflegehilfe
Own Azure-hosted ASP.NET Core microservices for chronic-care workflows, sustaining 99.8% uptime across 3,000+ patient interactions.
Shape HL7 FHIR-based patient, encounter, and observation profiles delivering a unified source of truth for clinical teams and integrations.
Implement SignalR telemetry, Application Insights alerting, and automated pipelines that surface deteriorating vitals in under three seconds.
Automated consultant outreach by orchestrating Twilio voice campaigns via n8n workflows and VAPI AI assistants, boosting successful client contacts by 55%.
Entlass Manager: Led the end-to-end build of the chronic-care coordination platform, standing up Azure-native microservices, clinical data flows, and patient-facing tooling from initial requirements through production release.
Power Dialer: Built the Twilio-driven consultancy auto-dialer and n8n workflows, raising client reachability to 85%.
Mario E.
Last position:
Developer and Consultant at Freelancer
Discover over 15,000 top freelancers
Statistics of experts using CQRS
Aggregated from the professional profiles of matched freelancers.
Experience
18 years
Position duration
3.5 years
Positions per freelancer
6
Top business areas
Information Technology, Product Development, Research and Development
Top industries
Information Technology, Education, Transportation
Bachelor's degree or higher
100%
Master's degree or higher
60%
Certifications per freelancer
1
Most common languages
German, English, 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 CQRS
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.
CQRS 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%)
- Education (67%)
- Transportation (67%)
- Healthcare (33%)
- Telecommunication (33%)
- Automotive (17%)
- Biotechnology (17%)
- Energy (17%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
What CQRS does
CQRS stands for Command Query Responsibility Segregation. The pattern separates operations that change state from operations that read state, allowing each side to serve a different purpose and scale independently. It is used in business systems where workflows, auditability or read performance make a single model difficult to maintain.
Core architecture
A CQRS solution usually has a command model for validating intent and applying business rules, plus one or more query models shaped for fast access. Changes may travel through events, messaging or direct synchronization. The design can be simple inside one service or extend across distributed bounded contexts.
Ecosystem and tooling
CQRS is an architectural pattern rather than a standalone product. Strong specialists work with the surrounding stack, including:
- Domain-driven design and bounded contexts
- Event buses, message brokers and asynchronous processing
- Event sourcing, projections and read-model rebuilding
- Relational and document databases for separate workloads
- APIs, observability, testing and deployment automation
Where companies use it
Companies bring CQRS into systems with complex state changes and demanding read paths. Typical examples include order and payment workflows, inventory, logistics, customer platforms, financial operations and collaboration software. In Berlin, specialists may support local product teams on-site or remotely, with communication in English or German depending on the organisation.
When freelance expertise helps
External expertise is useful when a team must assess whether CQRS is justified, separate a growing domain model or recover from inconsistent projections. It can also help during a migration from a monolith, an event-driven integration project or a redesign of reporting workloads. Signs that support is needed include unclear command ownership, duplicated business rules, slow queries and unreliable replay processes.
What strong specialists deliver
Experienced CQRS professionals explain the trade-offs before introducing more moving parts. They define commands, events and consistency boundaries clearly, document failure handling and make projections observable and repeatable. They also test business invariants, protect message contracts and leave the team with practical guidance for operating and evolving the system.
Frequently asked questions
Curious about CQRS? Here are the answers that come up again and again.
CQRS is used to separate state-changing commands from read-focused queries. This helps when business rules are complex, read and write workloads differ, or several views of the same domain are needed.
CQRS separates command and query responsibilities, while a conventional CRUD design often uses one model for creating, changing and reading data. CQRS can improve domain clarity and independent scaling, but it also introduces more components and consistency concerns.
CQRS and event sourcing are related but separate ideas. CQRS splits reads from writes; event sourcing stores state changes as events, and a system may use either pattern without requiring the other.
A strong CQRS specialist usually understands domain-driven design, messaging, database modelling and distributed-system reliability. Useful adjacent skills include event sourcing, API design, observability, automated testing and cloud deployment.
A CQRS project needs a specialist who can show sound decisions around consistency, message delivery, projection failures and domain boundaries. The right level depends on system complexity, but familiarity with the surrounding architecture matters more than having used the pattern in isolation.
CQRS can work well with remote collaboration when command ownership, event contracts and operational procedures are documented. Teams in Berlin should agree early on working language, meeting practices and access to logs, environments and domain experts.
Review a CQRS specialist's ability to explain trade-offs, not just diagrams or framework choices. Look for clear consistency guarantees, recoverable projections, meaningful tests, traceable messages and evidence that the design fits the domain.
CQRS is often unnecessary for a small system with straightforward data access and limited domain rules. A simpler model may be safer when separate read and write paths would add operational cost without solving a real scaling or modelling problem.
The average hourly rate of freelancers in Berlin, Germany who have used CQRS in their recent projects is 90 €, which corresponds to a daily rate of about 718 € based on an 8-hour working day.
Of the freelancers in Berlin, Germany who have used CQRS in their recent projects, 100% hold at least a Bachelor's degree and 60% hold at least a Master's degree.
On average, freelancers in Berlin, Germany who have used CQRS in their recent projects have 18 years of professional experience, with a single engagement typically lasting around 3.5 years.
The most common languages among freelancers in Berlin, Germany who have used CQRS in their recent projects are German (100%), English (100%), and Spanish (33%).
The most common industries among freelancers in Berlin, Germany who have used CQRS in their recent projects are Information Technology (100%), Education (67%), and Transportation (67%).
The most common business areas among freelancers in Berlin, Germany who have used CQRS in their recent projects are Information Technology (100%), Product Development (100%), and Research and Development (67%).
Main locations of FRATCH Experts, who have recently used CQRS
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
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Philipp Thomaschewski
FRATCH CEO
