JSON Experts in Essen
for reliable data exchange, matched in minutes with vetted and available freelancersHire experts who design robust data structures, connect REST APIs and validate complex payloads across web, mobile and enterprise systems. FRATCH matches you quickly and precisely with vetted, available freelancers who fit your technical needs.
Meet FRATCH Experts in Essen, who have recently used JSON
Fadi S.
Last position:
Data Scientist at E-Commerce
- Designed and developed a production-ready data platform based on Microsoft Fabric for an e-commerce company
- Built a scalable Medallion Architecture (Bronze, Silver, Gold) with Lakehouse and Delta Lake as the foundation for analytics and AI applications
- Developed a metadata-driven ETL platform with PySpark and a generic Incremental Loading Framework (SQL Server → Bronze → Silver → Gold)
- Developed reusable components for Microsoft Fabric Notebooks to standardize data integration, transformation, and validation
- Implemented automated data pipelines including monitoring, logging, error handling, and Delta MERGE strategies for stable production operations
- Built a business layer architecture for reporting, data warehousing, and reusable data products
- Integrated heterogeneous data sources via SQL Server, REST APIs, Amazon SP API, and Google Analytics 4
- Worked closely with business departments to analyze business requirements and translate them into scalable data architectures
Technologies: Microsoft Fabric, PySpark, Python, SQL Server, Delta Lake, Lakehouse, OneLake, Data Factory, Data Warehouse, REST APIs, Amazon SP-API, Google Analytics 4
Saruna M.
Last position:
Master's Thesis at Heinrich Heine Universität
- Title: Enhancing Syntactic Awareness in Transformer Language Models for Hindi Dependency Parsing
- Investigated syntactic knowledge captured by transformer language models (RoBERTa, XLM-RoBERTa) for Hindi dependency parsing, a morphologically rich and low-resource language.
- Developed structure-aware model variants (Struct_Roberta_hi, Struct_XLMR) by integrating a CNN-based parser network between transformer layers, inspired by the StructFormer architecture.
- Conducted extensive error analysis including label-wise, distance-based, direction-based, sentence length-based, and LVC/Non-LVC evaluations.
- Evaluated models on downstream NLP tasks (NER, POS tagging) using the IndicXTREME benchmark.
Manuel E.
Last position:
External Technical Lead for CI/CD, Architecture & Technical Governance at Insurance
- Technical lead for CI/CD modernization in the "Group Archive 4.0" system
- Architecture and steering responsibility according to the statement of work
- Setting up modern build and deployment processes
- CI/CD coaching and enablement of the internal development team
- Integration of modern DevOps, security, and compliance standards
- Ensuring technical governance, including collaboration with internal audit and BaFin
- Independently executing the modernization measures
- Supporting the team in adopting new technologies and methods
Loic N.
Last position:
Development of an app for managing Power Platform components at Hays GmbH
- Requirements analysis
- Provisioning of SharePoint sites and permissions
- Provisioning of SharePoint libraries and lists as data repositories
- Development of the UI with Power Apps
- Development of automations with Power Automate to transfer data from Power Apps using Dataverse connectors
- Creation, customization and management of Power Platform security roles
- Creation and management of Power Platform Pipelines
- Development of a UX design with Power Apps
Nils S.
Last position:
Backend System and Web Client for Replacing Electricity Meters for Energy Suppliers at Freelance
Design and implementation of a system for controlling the complete process of installing, removing, and replacing electricity meters by external service providers for an energy supplier
Automated retrieval of orders and available devices through defined interfaces (e.g. from SAP)
Orchestration of the process steps (assignment of meters, processing of meter data, transfer of updated information back to the source system) through a Spring-Boot backend
Provision of a React-based web client for operational tracking and control of orders, e.g. to continue failed process steps or resend notifications
Mugisha E.
Last position:
Freelancer Business Data Analyst at Study Boundless
- Manage WordPress websites, ensuring SEO-friendly structures and high-performance functionality
- Create and optimize Google Ads campaigns, leveraging data to enhance conversion rates and ROI
- Develop Looker Studio & Power BI dashboards to track customer behavior, sales trends, and digital performance
- Implement Google Tag Manager (GTM) and Google Analytics (GA4) to enable precise event tracking and reporting
Andreas A.
Last position:
IT-Application Manager at IHK-GfI
- Gathering, analyzing, specifying, and prioritizing requirements for the 'Archive and Delete' module of the Chambers of Industry and Commerce in a Scrum team
- Capturing and specifying screen/form designs, functionality, and data types in Confluence, as well as creating user stories in Jira
- Preparing PowerPoint presentations for the 'Archive and Delete' module
- Coordinating and supporting the Chambers of Industry and Commerce in the implementation of the module
- Writing SQL scripts for an Oracle database
- Technologies used: Scrum, Confluence, Jira, MS Office, Postman, JavaScript, REST API, JSON, DBVisualizer, SQL
Stefan W.
Last position:
Project team member at Environmental service provider
- Implementation and maintenance of an order management system
- RDBMS Oracle 19c
- Oracle Forms/Reports 12c/14c
- Oracle SQL
- XML processing
Discover over 15,000 top freelancers
Statistics of experts using JSON
Aggregated from the professional profiles of matched freelancers.
Experience
13 years (Germany: 19 years)
Position duration
1.4 years (Germany: 5.2 years)
Positions per freelancer
15 (Germany: 14)
Top business areas
Information Technology, Product Development, Business Intelligence
Top industries
Information Technology, Automotive, Education
Certification focus areas
Information Technology, Product Development, Audit
Bachelor's degree or higher
100% (Germany: 89%)
Master's degree or higher
83% (Germany: 56%)
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 29 Oct 2026.
Daily rate distribution
The chart shows how the daily rates of experts in this technology in Essen 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 Essen 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 29 Oct 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
JSON 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 (75%)
- Automotive (50%)
- Education (50%)
- Professional Services (50%)
- Government and Administration (50%)
- Retail (50%)
- Utilities (50%)
- Construction (38%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
Data format
JSON, short for JavaScript Object Notation, is a lightweight text format for representing structured data. It uses objects, arrays, keys and values that people can read and software can parse. Companies use it to move information between browsers, applications, services and databases.
Where JSON runs
JSON is a core format for REST APIs, configuration files, event payloads and document-oriented data stores. It supports web and mobile applications, integrations, dashboards and automated workflows. In Essen, specialists may support industrial, logistics, retail and service systems that exchange data across locations and business units.
Ecosystem and tooling
Strong JSON work connects the format to the systems around it. Experts commonly use REST, HTTP, OpenAPI, JSON Schema, jq and command-line tools, alongside JavaScript, TypeScript, Python, Java or .NET. They validate payloads, document contracts, transform data and inspect requests with tools such as Postman.
Typical deliverables
- API request and response structures
- JSON Schema definitions and validation rules
- Data transformation between services and vendors
- Configuration and deployment files
- Migration plans for inconsistent payloads
The deliverable may be a documented contract, a tested integration or a clean data model ready for production use. Good specialists also define how errors, missing values and optional fields should be handled.
When to hire expertise
Companies bring in freelance JSON specialists when integrations fail, payloads lack consistency or an API needs a clear contract. They can help during a new product launch, a system migration, a partner connection or a quality review. Remote collaboration often works well because schemas, examples and test cases can be reviewed asynchronously; on-site work in Essen can help when teams need close coordination with operational systems.
What strong specialists do
Quality goes beyond producing valid syntax. Strong professionals model data that is stable, readable and suitable for its consumers, while considering validation, versioning, security and performance. They test real edge cases, explain trade-offs clearly and trace malformed values back to their source. They also understand that JSON is a transport format, not a substitute for sound domain design.
Frequently asked questions
Need clarity? These are the questions we hear most often about JSON.
JSON is used to exchange structured information between web applications, mobile clients, APIs, databases and external partners. A specialist can also use it for configuration, event messages, reporting data and integration workflows.
JSON is usually more compact and easier to process in web applications than XML, while YAML is often chosen for human-friendly configuration. The right choice depends on validation, comments, document complexity, existing interfaces and the systems that consume the data.
A strong JSON specialist should understand REST APIs, HTTP methods, authentication, JSON Schema and API documentation. Experience with JavaScript or TypeScript, backend languages, databases, testing tools and data transformation is also valuable.
The required depth depends on the work. Simple payload adjustments may need a professional familiar with API testing, while schema design, large migrations or integration troubleshooting calls for someone who understands contracts, versioning, validation and production failure modes.
Yes, JSON projects are often well suited to remote collaboration because schemas, examples, API specifications and test results can be shared digitally. On-site sessions in Essen can still be useful when the work involves plant systems, internal processes or close coordination with local teams.
Review whether the JSON structures are valid, consistent, documented and easy for consuming systems to use. Ask for examples of validation rules, error handling, test coverage, versioning decisions and how the specialist handled ambiguous or incomplete data.
JSON is independent of JavaScript, even though its syntax originated in that ecosystem and the names are closely associated. A professional can work with it using Python, Java, C#, Go or other languages, provided they understand parsing, serialization and data contracts.
A capable JSON professional can resolve malformed payloads, incompatible field names, incorrect data types, missing values and unclear API contracts. They may also improve validation, normalize data between systems and make integrations easier to monitor and maintain.
The average hourly rate of freelancers in Essen, Germany who have used JSON in their recent projects is 66 €, which corresponds to a daily rate of about 525 € based on an 8-hour working day.
Of the freelancers in Essen, Germany who have used JSON in their recent projects, 100% hold at least a Bachelor's degree and 83% hold at least a Master's degree.
On average, freelancers in Essen, Germany who have used JSON in their recent projects have 13 years of professional experience, with a single engagement typically lasting around 1.4 years.
The most common languages among freelancers in Essen, Germany who have used JSON in their recent projects are German (100%), English (100%), and French (25%).
The most common industries among freelancers in Essen, Germany who have used JSON in their recent projects are Information Technology (75%), Automotive (50%), and Education (50%).
The most common business areas among freelancers in Essen, Germany who have used JSON in their recent projects are Information Technology (100%), Product Development (88%), and Business Intelligence (75%).
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 
Cologne 
Frankfurt 
Stuttgart 
Dusseldorf 
Dortmund 
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
