REST API Experts in Leipzig
matched in minutes by AIHire experts who design clear API contracts, connect web and mobile applications, and secure integrations with OAuth 2.0 and OpenAPI. FRATCH matches you quickly with vetted, available freelancers whose REST API experience fits your project.
Meet FRATCH Experts in Leipzig, who have recently used REST API
Sascha W.
Last position:
Lead Product Owner CADKit at Ottobock SE
- Repositioned and provided functional leadership for a CAD web platform to digitally transform the prosthetics manufacturing process worldwide
- Translated the CPO vision into a technical roadmap and guided an interdisciplinary team of developers, designers, and QA specialists
- Delivered complex 3D interfaces based on Vue.js and Three.js
- Rolled out 8 scalable web apps worldwide, increasing production efficiency by 80%
Gwen G.
Last position:
Senior Ruby on Rails & DevOps Developer at Sapiens
Further development of a software solution for managing audit applications and audit notifications according to §106d SGB V for the Association of Statutory Health Insurance Physicians in Hamburg.
- Developed numerous features, optimised performance, refactored code and analysed errors
- Refactored the development container setup
- Optimised the Gitlab-CI build pipeline
- Introduced improvements to the team workflow
Julian H.
Last position:
Working Student / Master's Thesis Student in Software Development at Scale GmbH
- Tech stack: Python, Qt, tensorflow.js, plotly, Angular, TypeScript, HTML, CSS, Git
Knud W.
Last position:
Lead Programmer, Architect and Deputy Product Owner at Bundesagentur für Arbeit
- Lead programmer, architect and deputy product owner
- Completed transition from zPDV to STEP
- Ensured quality of C++ and Perl sources through automated and manual checks
- Supported resolution of incidents and errors in testing
- Implemented batch for supplementary assignment of payment run numbers
- Implemented batch for distribution of SGB 2 information to the central payment unit
- Supported replacement of Solaris with Linux
- Upgraded gcc from 7.4 to 9.3
- Programmatically generated Makefiles from Borland projects for builds
- Extended funding data with new attribute “Kennzeichen Fahrtkosten Praktikum”
- Programmatically generated XSD and WSDL files from IDL definitions
- Represented the product owner when needed
- Implemented batch for one-time payment processing
- Developed generator for Liquibase files
- Implemented and maintained regular anonymization of production data
- Supported migration from SLES 12 to SLES 15
- Supported introduction of mutual TLS
- Implemented batch for sending deletion impulses to EDA BE
- Organized script directory structure
- Investigated potential introduction of String-Latin and implemented minimal solution
- Remediated security findings identified by CheckMarx
- Supported PAP recalculations and general change notices
- Converted ERP interfaces from SOAP to REST
- Planned technical and business topics such as register modernization, cash register security, training costs, four-eyes principle
Natascha F.
Last position:
Senior iOS Developer - ANÜ at Stadtwerke München GmbH
- Development of an iOS app that combines public transport and sharing services
- Collaboration according to Scrum in a large cross-functional team
- Creation of reusable components with SwiftUI and Combine
- Development of a custom solution for Apple Maps
Thomas P.
Last position:
Product Owner & AI Automation Architect (B2B) at Ihre-Hygieneberatung
Development of a digital audit application for inspections in medical facilities. The goal is to connect on-site data collection, voice recording, documentation and downstream processes in one end-to-end, AI-supported workflow.
Design and development of a Flutter audit app with Claude Code for the structured execution and documentation of inspections.
Processing of voice recordings captured in the app through automatic transcription and AI-supported creation of structured inspection reports, followed by an approval process
Connecting various data sources such as email, Odoo 19, attendance records and Google Drive via n8n to automate billing and follow-up processes
Automatic provision of required documents and email delivery through n8n-controlled workflows, including the use of LLMs for text creation
Skills: Flutter, Claude Code, LLM Integration, n8n, Odoo 19, Google Drive, Process Automation
Frank R.
Last position:
eCommerce Software Developer at WirTube-Shop
- Maintenance and system handover
- Planning and carrying out core and plugin updates
- Developing a plugin to extend invoice creation and payment via Flow Builder
Hannes W.
Last position:
intermedix GmbH / CGM Deutschland AG
Rule-based software for managing, planning, and providing promotional materials in the pharmaceutical industry
High performance, high availability
Fullstack, DevOps (CI/CD)
Python, PostgreSQL, Vue.js, Typescript, Docker, Docker-Compose, Nginx
Successfully transformed old Excel-based processes into an optimized product that has been in production since 2024
Mostafa S.
Last position:
Freelance Senior Software Engineer & AI Consultant at Self-employed
- Led the development of a complex geospatial data platform, engineering an end-to-end system for processing and analyzing high-resolution aerial imagery.
- Engineered a scalable backend responsible for on-the-fly map tile serving and running complex data analysis queries using PostGIS and Python.
- Developed and trained custom computer vision models using Python, PyTorch, and YOLOv8 to perform object detection and segmentation on large-scale datasets.
- Built modern, responsive user interfaces and data visualization dashboards using Next.js, TypeScript, and React.
- Gained practical expertise in geospatial libraries such as GDAL and Rasterio for processing and manipulating raster and vector data.
- Managed the entire project lifecycle, from initial technical architecture and database design to final deployment using Docker.
Andreas M.
Last position:
Managing Director at ESIS-ERP GmbH
- Took over management of the company
Peter T.
Last position:
Freelance Go Developer/DevOps Engineer at IONOS SE
- Developed an API for customers to provide NFS shares in the cloud
- Created Kubernetes operators and services with REST APIs in Go
- Used LinuxKit to provision VMs
Jan B.
Last position:
API-Engineer at Freelance
- API-first product design (OpenAPI 3, HAL) and development (NodeJS)
- Setting up DevOps pipelines with GitHub Actions in an AWS architecture
- Technologies: OpenAPI 3, REST, HAL, NodeJS, JavaScript, TypeScript, AWS, AWS Lambda, Docker, GitHub Actions
Sebastián K.
Last position:
Smart Charging at Mercedes-Benz, MBTI
Agile software development in an interdisciplinary environment
Cross-team collaboration to achieve important milestones
Independently developing new and improving existing features
Estimation, refinement, implementation, and presentation
Finding solution ideas, analyzing problems, rolling out bug fixes
Writing automated tests, manual testing, log and error analysis
Ensuring high availability, fault tolerance, and scalability of the production environment
Rolling out releases and multi-stage infrastructure
Setting up alerts and monitoring
Pair programming, code reviews, documentation
On-call duty, 3rd level support
Event-Driven Architecture, Clean Code, Hexagonal Architecture
Microservices based on Go (Gin), Java 21 (Spring Boot 3), Python (FastAPI)
Terraform/OpenTofu, KQL, SQL, JSON, REST, Helm, ArgoCD, AzureCLI, K9s, OAuth2
Postgres, Redis, Kafka, Azure EventHub, Kubernetes, nginx, Ingress
AppInsights, LogAnalytics, OpenTelemetry, Datadog, OpenAPI 3, Swagger
Azure DataExplorer, Storage, KeyVault, Container Registry, Azure Functions,…
Junit5/Jupiter, testify, RestAssured, Docker Compose, Wiremock
IntelliJ, Scrum, Kanban, Teams, Confluence, OpsGenie, Arc42
GitHub CI/CD, GitLab CI/CD, Azure DevOps
EV charging protocols (EVSE, OCPP, V1G, V2G)
Linus H.
Last position:
Software Developer at Check24 Vergleichsportalreise Reise Gmbh
- Designing, developing, and maintaining web portals, including creating and connecting interfaces to other systems (APIs)
- Performing error analysis and troubleshooting
- Designing and implementing data structures
- Refactoring software components to improve maintainability
- Creating user interfaces
- Web portal for monitoring error messages (PHP, MySQL, Elasticsearch, ExtJS 5.0, Symfony)
- Web portal for electric car buying advice, further development, and providing a white-label solution for a startup in the e-mobility sector (PHP, Symfony, JavaScript, Bootstrap 5)
- Providing a REST API for a healthcare app (PHP, Symfony API Platform, AWS)
- Developing middleware for data exchange between multiple applications (PHP)
Discover over 15,000 top freelancers
Statistics of experts using REST API
Aggregated from the professional profiles of matched freelancers.
Experience
19 years (Germany: 17 years)
Position duration
2.4 years (Germany: 2.9 years)
Positions per freelancer
11 (Germany: 12)
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Retail, Healthcare
Certification focus areas
Project Management, Operations, Product Development
Bachelor's degree or higher
82% (Germany: 92%)
Master's degree or higher
55%
Certifications per freelancer
1 (Germany: 3)
Most common languages
German, English, Spanish
Speak two or more languages
93% (Germany: 97%)
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 Leipzig 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 Leipzig using REST API
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.
REST API 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 (93%)
- Retail (50%)
- Healthcare (43%)
- Professional Services (43%)
- Tourism (43%)
- Automotive (29%)
- Energy (29%)
- Manufacturing (29%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
What REST APIs do
REST API is a common way for software systems to exchange data over HTTP. It exposes resources through predictable URLs and uses methods such as GET, POST, PUT and DELETE. Responses usually use JSON, making REST APIs practical for web apps, mobile products, partner integrations and internal services.
Core design work
Strong REST API work starts with a clear resource model and stable contracts. Experts define endpoints, request and response schemas, status codes, pagination, filtering and error formats. They also plan versioning and backward compatibility so clients can evolve without unexpected outages.
Ecosystem and tooling
REST API projects often involve OpenAPI or Swagger for documentation and contract review. Professionals may work with API gateways, OAuth 2.0, JWT, webhooks, Postman, automated tests and observability tools. They connect APIs to databases, message queues and services built with Java, .NET, Node.js, Python or other stacks.
Where companies use it
- Connect frontend applications with backend services
- Expose product data to mobile apps and external partners
- Link SaaS tools, payment services and business systems
- Replace fragile point-to-point integrations with documented endpoints
REST APIs run across commerce, logistics, manufacturing, finance, healthcare and public services. Companies in Leipzig may need specialists who can collaborate on-site, remotely or in a hybrid team and communicate clearly with German- and English-speaking stakeholders.
When to bring in expertise
Freelance support helps when an API needs a reliable design before implementation, when undocumented endpoints block delivery, or when integrations fail under real usage. It is also useful for modernising legacy services, introducing authentication, preparing an OpenAPI specification or improving test coverage and monitoring.
What quality looks like
The best professionals think beyond individual endpoints. They check naming consistency, validation, security, idempotency, performance and useful documentation. They test failure paths as carefully as successful requests, explain trade-offs to product and engineering teams, and leave behind an API that other specialists can safely extend.
Frequently asked questions
Before you brief your next project: the most common questions about REST API.
A REST API lets separate software systems exchange resources over HTTP. Companies use it to connect web and mobile applications with backend services, partner systems, databases and SaaS products.
A REST API usually exposes resource-oriented endpoints and works well with standard HTTP caching, status codes and tools. GraphQL gives clients more control over returned fields, while SOAP provides stricter messaging and contract conventions for selected enterprise environments.
A strong REST API specialist should understand HTTP, JSON, authentication, databases and automated testing. OpenAPI, OAuth 2.0, API gateways, cloud deployment, logging and version control are also valuable adjacent skills.
The right REST API experience depends on the risk and scope of the system, not simply its endpoint count. A small internal integration may need focused implementation skills, while a public or partner-facing API calls for deeper knowledge of security, compatibility, monitoring and release planning.
Yes, REST API work is often well suited to remote collaboration because specifications, code reviews, test collections and documentation can be shared online. Leipzig teams should still agree on communication routines, security access and whether German or English is required for stakeholder work.
Review whether a REST API has consistent resource naming, useful status codes, clear schemas and documented error behaviour. Ask for evidence of automated tests, authentication design, backward compatibility, monitoring and practical documentation for client teams.
Choose a REST API when resources map naturally to HTTP operations and broad client compatibility matters. Another style may fit better when clients need highly tailored data queries, real-time streaming or strict message contracts that REST does not provide as naturally.
A capable REST API freelancer can deliver endpoint designs, an OpenAPI specification, implementation, automated tests and client-facing documentation. Depending on the project, the scope may also include authentication, deployment configuration, monitoring dashboards and a migration plan for existing consumers.
The average hourly rate of freelancers in Leipzig, Germany who have used REST API in their recent projects is 90 €, which corresponds to a daily rate of about 717 € based on an 8-hour working day.
Of the freelancers in Leipzig, Germany who have used REST API in their recent projects, 82% hold at least a Bachelor's degree and 55% hold at least a Master's degree.
On average, freelancers in Leipzig, Germany who have used REST API in their recent projects have 19 years of professional experience, with a single engagement typically lasting around 2.4 years.
The most common languages among freelancers in Leipzig, Germany who have used REST API in their recent projects are German (93%), English (93%), and Spanish (14%).
The most common industries among freelancers in Leipzig, Germany who have used REST API in their recent projects are Information Technology (93%), Retail (50%), and Healthcare (43%).
The most common business areas among freelancers in Leipzig, Germany who have used REST API in their recent projects are Information Technology (100%), Product Development (100%), and Quality Assurance (57%).
Main locations of FRATCH Experts, who have recently used REST API
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 
Essen 
Bremen 
Dresden 
Hanover 
Nuremberg Request a free demo
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FRATCH CEO
