JSON Experts in Cologne
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Meet FRATCH Experts in Cologne, who have recently used JSON
Hooman Behmanesh
Last position:
Fullstack Developer at Möbel Roller GmbH
- Further development of the existing e-commerce platform based on SAP Commerce (Hybris) to meet the growing demands of digital commerce.
- Ensuring the scalability and performance of the backend, so the platform remained stable and efficient even under heavy user load.
- Development and integration of new OCC REST APIs and services for modular extensions and flexible adjustments, to implement new features quickly.
- Optimization of data flows and interfaces, which significantly improved platform efficiency and system performance.
- Ensuring a maintainable and scalable code base by using Clean Code principles, proven design patterns, and a future-proof architecture.
- Reduction of errors through extensive testing with JUnit, Mockito, and load tests with Gatling, supported by the introduction of automated test processes.
- Improved system performance through targeted refactoring measures and efficient database queries, especially to handle peak loads.
- Use of modern cloud and monitoring tools such as Kubernetes, Google Cloud Platform (GCP), and Grafana to ensure a stable and monitored infrastructure.
- Clear improvement in efficiency, scalability, and reliability of the platform, which now meets the demands of a dynamic and growing e-commerce market.
Henning Uiterwyk
Last position:
Senior Expert Data Governance, Master Data Quality and Data Migration at E.ON
- Planning and implementation of a migration strategy for master and transaction data for the continuous loading of a cloud-independent database
- Creation and pilot implementation of a company-wide Business Data Model for customers, suppliers, contracts, products, prices, consumption, invoices, and dunning
- Concept and consulting for a Data Governance Framework incl. definition of committees, roles, processes, and metadata model
- Operationalization of the Data Governance Framework with definition of data standards
- Sub-project management in two pilot projects (PoCs) for Data Governance systems (ErwinDIS and Atlan)
- Training and coaching the data team in migration, data quality, and data modeling
Muhammad Jamshaid Iqbal
Last position:
Embedded Linux Intern – IoT Sensor Prototype Development at DHL
- Built a modular C++ 20 embedded Linux acquisition system on a Raspberry Pi, synchronizing IMU and dual-camera data streams to sub-millisecond accuracy.
- Integrated retro-reflective and contrast sensors to trigger acquisition and detect gaps between sorter rails.
- Implemented SPI & I2C sensor communication, GPIO interrupt handling with libgpiod, and CSV & JSON output.
- Designed a multi-threaded acquisition pipeline and an SPSC queue between acquisition and writer threads.
- Built a Python/HTML/CSS based web-server and validated the prototype in a DHL warehouse for defect detection.
- Documented software behavior, configuration, and results for maintainable handover and further development.
Stanislaus Stelle
Last position:
Security Consultant at Rohde & Schwarz AG at Star Labs GmbH
- Worked on FPGA enhanced network encryption device with secure boot, TPM2.0 and smart card integration for BSI approved usage with Post Quantum Cryptography
- Developed and audited Linux drivers
- Collaborated using GitLab, Gerrit, Confluence and Jira
- Technologies: C, C++, Secure Boot
Alexander Rautzenberg
Last position:
Business Analyst at Financial Services Provider Landesbank
The Helaba ATLAS project aims to modernize core systems and make them future-proof. As part of the subproject, the existing legacy system for international payments is being replaced by a modern web-based application.
- Analysis of functional and technical requirements
- Analysis and optimization of business processes
- Process modeling
- Preparation and facilitation of workshops
- Defining project scope and prioritizing requirements
- Business process management (analysis, modeling, and optimization)
- Specification of user stories
- Designing business and authorization concepts
- Testing and acceptance
- Designing mockups in Figma
- Creating the UI/UX style guide for web applications Approach: Scrum (agile) Technologies: Jira, Confluence, MS Teams, Conceptboard, Java, Vaadin, Figma
Jens Hagemeyer-Lee
Last position:
#52 Test Manager in Safety-Critical Infrastructure at Telecommunications Company
- Network elements, network, operational and operator-related systems
- Supporting around 20 different products (managed agile)
- Requirements analysis and management (functional and non-functional)
- Test concept and planning (scope, test phases, effort, schedule, resources, organization, etc.)
- Aligning approach with clients and service providers
- Managing and assisting in creation of test cases for system, integration and end-to-end tests
- Guiding and supporting test execution
- Defect management and planning bug fixes with external providers
- Preparing and facilitating workshops
- Regular reporting and creating automated test reports
- Further development of agile testing methodology and configuration of supporting tools
- Conceptual support in developing a quality seal for rating product and service quality of internal and external providers
- Requirements engineering based on ISO/IEC 25010, Scrum, SaFE
- BMC Remedy, Atlassian Confluence, Atlassian Jira (including plugins Xray, Structure), Microsoft Office (incl. Visio), Obsidian, doxis document management system, Gitlab, Obsidian
Manuel Schneider
Last position:
Project Manager at Univention
Industry: digital sovereignty, public sector
Content:
- Project steering (teams: consulting, development, testing, deployment/operations)
Products and standards:
- Jira, Confluence, Asana, Miro, Mural
- Open Source, Keycloak, Open Xchange, ownCloud
Armen Markarian
Last position:
CTO/CPO Platform & Technology at Green Mobility Holding
- Overall responsibility for platform transformation across ERP, CRM, PIM, and AI-driven process automation
- ERP transformation: Implementing and migrating to Microsoft Dynamics 365 Business Central
- CRM & growth stack: Implementing HubSpot as the central CRM and a platform for lead and marketing automation
- Product data & commerce enablement: Introducing an ePIM to scale category management and digital commerce processes
- AI-driven process automation: Designing and implementing agent-based AI workflows to automate processes in business services, accounting, tender management, and marketing
- Building a scalable platform organization including product development, DevOps, UX, cloud engineering, and corporate IT
- Implementing modern product and portfolio governance (e.g., OKRs, portfolio boards, value-based roadmaps) to manage technology-driven initiatives
- Harmonizing heterogeneous system landscapes and transforming them into a modular, scalable platform architecture (ERP, CRM, PIM, integrated customer journeys)
- Coaching and developing product owners, tech leads, delivery managers, and UX teams to build a scalable product organization
Kai Birkenbusch
Last position:
Freelance CPQ Consultant (Full-Time) at Freelance CPQ Consultant
- Independent CPQ consulting for a portfolio of industrial manufacturers, including Scheidt & Bachmann, Trützschler Group SE, and Weiss Klimatechnik GmbH (Schunk Group)
- Full project coverage: requirements analysis, concept, system design, implementation, testing, and international go-live support
- Deep integration work with SAP ECC (material master replication, SD document creation, material creation, general APICONNECT and other web service interfaces)
- Process consulting: analysis and optimization of internal quoting processes for sales and management
- Knowledge transfer/coaching and pair programming to strengthen internal team skills
Alexander Vasiliev
Last position:
Senior DevOps / Platform Engineer at Kaufland e-commerce / real.digital (ex hitmeister.de)
- Evolved the platform from bare-metal infrastructure with a monolithic PHP application to a hybrid Google Cloud architecture with Go microservices on Kubernetes
- Managed and scaled a production infrastructure with 300+ VMs and dozens of clusters, including MySQL, PostgreSQL, MongoDB, RabbitMQ, Redis and Elasticsearch clusters
- Designed architecture, deployment, monitoring, performance analysis, and upgrades for all platform services using Terraform and Ansible
- Migrated observability systems from ELK and Prometheus to Datadog, managed with Terraform
- Introduced Jenkins CI/CD with SonarQube integration and automated tests to speed up feedback cycles
- Containerized the testing environment and implemented GitLab CI pipelines for Docker image builds, static code analysis, and infrastructure tests
- Performed zero-downtime migrations of MySQL and MongoDB clusters to Google Cloud
- Developed reusable Ansible roles for database clusters and automated data obfuscation for staging environments
- Decomposed monolithic databases and migrated to microservice architectures
- Built tools to detect and optimize slow queries in MySQL and MongoDB
- Conducted online schema migrations with pt-online-schema-change without downtime windows
- Developed internal Go applications for batch queries, GitLab-Jira integration, and MongoDB backup recovery
- Technologies: Debian, Ubuntu, Alpine, Go, Bash, Python, PHP, SQL, GitLab CI, Jenkins, Drone CI, MySQL, MongoDB, PostgreSQL, Redis, Elasticsearch, RabbitMQ, Kafka, Docker, Kubernetes, Nomad, Ansible, Terraform, Grafana, ELK, Prometheus, Datadog, Nagios, Zabbix, Nginx, HAProxy, Vault, Helm, SonarQube, Filebeat, Auditbeat, Google Cloud, AWS
Piet Althoff
Last position:
Frontend at Value Finance GmbH
- Developed a customer-facing application for a team of realtors to manage insurance and financial contracts
- Provided real-time insights into various insurance products, allowing realtors to manage, compare, and recommend contracts to clients
- Implemented a complex, reactive SVG visualization that displays key contract metrics for client presentations
- Worked with Nuxt 3, Tailwind, Google Firebase on the frontend and Node.js, MongoDB, PostgreSQL on the backend
- Followed Kanban, SCRUMBan, and Scrum methodologies
- Began learning Rust
Vladimir Maznicenko
Last position:
Developer at Financial services provider
- Support and further development of a framework for developing applications in a banking association: DynS/OSPE
- Migration of the framework to Java 11 and Java 17
- Java8, Java11 and Java17, Spring, Spring-Batch, Spring WebServices, Spring-Security, Spring-Data, JPA, Hibernate, OpenSource libraries etc.
- XML, JAXB, JSON, REST and SOAP services, DB2, Oracle, WebSphere or Liberty AS, FreeMaker, Junit, mock libraries, JaCoCo, Maven, IntelliJ, Eclipse, GitHub, SVN, Jira
Louis Nguenkam
Last position:
Specialist in Adobe Experience Manager & Microservices at Nguenkam Consulting & Engineering
Java 11/21
Springboot
Swagger/OpenApi
Azure Pipelines
Trivy Integration
Apache Sling
OSGI
Java Content Repository (JCR)
Apache Jackrabbit Oak
Adobe HTL
GraphQL
Maven
GitLab
IntelliJ
Azure Cloud
Azure DevOps
Terraform
AEM specialist in the Scrum team
Development and deployment of microservices via Open API interfaces
Operation of microservices in the Azure Cloud
Implementation of AEM modules and integration with microservices
Member of the knowledge transfer team and a backend coordination team
Peter Brungs
Last position:
Data Warehouse Consultant (Development and Analysis) at Atruvia AG
- Developed and enhanced ETL loading jobs with IBM DataStage and optimized SQL in an IBM DB2 environment as part of the Agree21 data migration
- Analyzed data quality and developed test procedures
- Created PowerShell scripts and documented GIT deployment processes
- Technologies: RedHat Linux, IBM DB2 with DBVisualizer, IBM InfoSphere DataStage 11.7, JIRA, TortoiseGIT, TortoiseSVN, PowerShell scripts
Ingo Cousin
Last position:
Founder, freelance CMS expert at CMS Consulting Cousin
- Freelance work as a CMS expert
Discover over 15,000 top freelancers
Statistics of experts using JSON
Aggregated from the professional profiles of matched freelancers.
Experience
21 years (Germany: 19 years)
Position duration
2 years (Germany: 1.9 years)
Positions per freelancer
15 (Germany: 14)
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Banking and Finance, Retail
Certification focus areas
Information Technology, Product Development, Project Management
Bachelor's degree or higher
88%
Master's degree or higher
50% (Germany: 56%)
Doctorate
6% (Germany: 11%)
Certifications per freelancer
2
Most common languages
German, English, French
Speak two or more languages
100% (Germany: 98%)
Based on our profile pool as of 30 Aug 2026.
Daily rate distribution
The chart shows how the daily rates of freelancers in this technology in Cologne are distributed, based on recent contracts on our platform. Each bar covers a rate range — its height shows how many freelancers charge within that range.
Average rates of experts in Cologne using JSON
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 30 Aug 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
About the technology
Core format
JSON, short for JavaScript Object Notation, is the common way to move data between services, apps, and scripts. It is simple to read, easy to generate, and widely supported across web stacks, cloud services, and mobile apps. Strong specialists know where JSON fits best and where stricter formats are safer.
Typical work
- API requests and responses
- Configuration files for services and tools
- Event payloads and webhooks
- Data export, import, and integration feeds
- Documents that use nested records and arrays
Skills around it
Good professionals work comfortably with JSON Schema, REST, HTTP, and validation logic. They also understand escaping, encoding, nested structures, and how to keep payloads stable as systems change. In Cologne, this often matters for teams running commerce, logistics, media, and internal business platforms.
When to bring in help
Bring in freelance expertise when payloads break, APIs drift, or integrations become hard to maintain. Specialists are also useful when teams need cleaner contracts between services, better validation, or a review of large document structures. They can help both remote teams and local groups that prefer on-site workshops in Cologne.
What strong experts do
Strong experts keep JSON clean, predictable, and easy to consume. They reduce ambiguity, remove duplicate fields, and design structures that fit real use cases instead of forcing every system into one shape. They also spot issues early, such as invalid nesting, bad naming, or inconsistent date handling.
Quality signs
- Clear field names and stable object shapes
- Valid data that passes schema checks
- Consistent handling of null, empty, and missing values
- Good support for versioned APIs and backward compatibility
- Documentation that matches the actual payloads
Frequently asked questions
Curious about JSON? Here are the answers that come up again and again.
JSON is used to exchange structured data between services, browsers, mobile apps, and automation tools. It is common in APIs, configuration files, event messages, and data exports. Teams choose it because it is compact, readable, and easy to parse.
No. JSON looks similar to JavaScript object syntax, but it is a data format, not a programming language. That difference matters because valid JSON has stricter rules for quotes, commas, and supported value types.
Bring in a JSON specialist when integrations keep failing, payloads are inconsistent, or schema changes cause breakage. They are also useful when a team needs cleaner API contracts or a review of nested data structures. This is common in system integration work across Cologne-based teams as well as remote setups.
JSON is usually lighter and easier for APIs than XML, while YAML is often friendlier for human-edited configuration. The right choice depends on the task: JSON fits service-to-service data exchange well, XML still appears in some enterprise systems, and YAML is common in tooling and config. A good specialist helps choose the format that matches the system.
A strong JSON freelancer should also know REST, HTTP, validation, and API design. JSON Schema is often important when strict contracts are needed. Awareness of encoding, date formats, and error handling is also useful.
Simple tasks may only need a focused JSON expert who can clean up payloads or fix parsing issues. More complex work, such as versioned APIs or large integration layers, needs someone who understands schema design, compatibility, and downstream consumers. The harder the data flow, the more value an experienced specialist brings.
Most JSON work can be done remotely because the deliverables are usually files, schemas, APIs, and reviews. On-site collaboration can help when teams need to align many systems or agree on data contracts quickly. In Cologne, both models are common depending on the project setup.
Look for a JSON expert who writes valid, predictable structures and explains design choices clearly. Good work is easy for other systems to consume, handles optional fields sensibly, and avoids unnecessary complexity. Clean samples, careful schema use, and clear documentation are strong signs.
The average hourly rate of freelancers in Cologne, Germany who have used JSON in their recent projects is 107 €, which corresponds to a daily rate of about 860 € based on an 8-hour working day.
Of the freelancers in Cologne, Germany who have used JSON in their recent projects, 88% hold at least a Bachelor's degree, 50% hold at least a Master's degree, and 6% hold a doctorate.
On average, freelancers in Cologne, Germany who have used JSON in their recent projects have 21 years of professional experience, with a single engagement typically lasting around 2 years.
The most common languages among freelancers in Cologne, Germany who have used JSON in their recent projects are German (100%), English (100%), and French (32%).
The most common industries among freelancers in Cologne, Germany who have used JSON in their recent projects are Information Technology (95%), Banking and Finance (53%), and Retail (53%).
The most common business areas among freelancers in Cologne, Germany who have used JSON in their recent projects are Information Technology (100%), Product Development (95%), and Quality Assurance (63%).
Main locations of FRATCH Experts, who have recently used JSON
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.
Berlin 
Hamburg 
Munich 
Frankfurt 
Stuttgart 
Dusseldorf 
Dortmund 
Essen 
Nuremberg Request a free demo
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Philipp Thomaschewski
FRATCH CEO
