Find the right Integration Developers in Germany matched in minutes from over 15,000 CVs with the power of AI.
Need API integration, ERP and CRM connectivity, or middleware work for SAP, MuleSoft, Boomi, Azure Integration Services, or Kafka? Get freelance integration developers who build stable interfaces, fix data flows, and keep systems in sync, fast and precisely matched with vetted, available experts.
About the role
What they do
Integration developers connect systems that must exchange data without friction. They build interfaces, map fields, transform payloads, and keep business processes flowing across internal and external applications.
- Design API and file-based integrations between ERP, CRM, e-commerce, and internal tools
- Build and maintain middleware, message flows, and event-driven connections
- Handle data mapping, validation, error handling, and retries
- Document interfaces, dependencies, and technical handovers
Common tools
A strong integration developer works comfortably across modern APIs and enterprise stacks. In practice, that can mean REST, SOAP, JSON, XML, OAuth, queues, ETL jobs, and platforms such as MuleSoft, Boomi, SAP CPI, Azure Integration Services, or Kafka.
They also know how to read logs, trace payloads, and debug issues across systems without disrupting operations. The best freelancers are careful with naming, versioning, security, and message structure, because small mistakes can break many downstream processes.
When to bring one in
Companies hire an integration developer when systems need to talk to each other and the internal team is already busy. That is common in ERP rollouts, CRM migrations, platform upgrades, merger projects, and the launch of new partner interfaces.
In Germany, this often comes up in manufacturing, logistics, retail, finance, and B2B software teams that work with SAP landscapes, local service providers, or mixed on-site and remote stakeholders. A freelance specialist is useful when you need focused delivery, not a long hiring cycle.
What good looks like
A strong integration developer does more than code connectors. They understand business processes, ask the right questions about source and target systems, and spot data problems before they become production incidents.
- Clear logic for mapping, transformation, and fallbacks
- Solid experience with APIs, middleware, and messaging
- Careful testing in development, staging, and release paths
- Practical documentation that operations and developers can use
- Calm debugging when multiple systems fail at once
Freelance fit
Freelance integration developers are a good fit when the scope is specific, technical, and time-sensitive. They can join for design, implementation, rescue work, or a short transition period after go-live.
For distributed teams, remote collaboration works well when requirements, access, and test data are prepared early. In Germany, on-site workshops can still help when many departments are involved or when older systems need careful coordination.
Choosing the right person
Look for evidence of real delivery in complex environments. A reliable integration developer can explain interface decisions in plain language, show how they handled failures, and describe how they reduced support effort after release.
The best candidates balance software engineering discipline with process thinking. They are not just coders; they are the people who keep connected systems stable when business operations depend on them.
Meet FRATCH Integration Developers
Oleg Orlov
Senior Software Architect C#/.NET | BI, Data & AI Integration
Last position:
Senior Software Developer / BI Integration Developer Power BI, C# at Telecommunications
Embedded Analytics & AI-assisted BI
Design and development of an integrated analytics solution based on ASP.NET Core, Power BI Embedded, and LLM services to provide contextual business information.
Development of an AI agent with Function/Tool Calling for secure orchestration of REST APIs, SQL data sources, and technical services within defined business processes.
Build-up of automated BI workflows including workspace management, deployment processes, and scheduled refresh via the Power BI REST API.
Implementation of secure service-to-service communication with Microsoft Entra ID and service principal, as well as integration into existing enterprise system landscapes.
Technologies: ASP.NET Core, C#/.NET, Power BI Embedded, Power BI REST API, LLM API, AI Agents, Function/Tool Calling, Entra ID
Thomas Langer
Consultant for AI, Electronics Development and System Integration
Last position:
Consultant for AI-driven process automation at Lumiz
AI-driven automation of purchasing on a printing company's website, including selecting delivery times, order options, ordering, payment, and uploading print data from the Lumiz Cloud.
Marc Smyk
Fullstack Engineer | Java & Spring Boot | Angular | System Integration
Last position:
Fullstack Developer at PLANT-MY-TREE
PLANT-MY-TREE®-per-order
The application allows Shopify merchants to automate tree-planting orders for each incoming order. By integrating ecological contributions directly into the checkout process, manual work for tracking and billing reforestation initiatives is eliminated. The system increases transparency for end customers through real-time visualizations of the ecological impact directly in the storefront. The architecture is based on a modular monolith with Spring Boot in the backend and an integrated React app inside the Shopify admin area. The solution uses webhooks for event-driven capture of order data and integrates the ERP system weclapp for automated monthly invoicing. An app proxy mechanism provides dynamic statistics such as CO2 compensation and planted trees without any performance loss for the merchant shop.
Tasks:
- Design of the modular software architecture based on Spring Modulith to ensure high maintainability
- Development of the event-driven business logic for evaluating Shopify orders using webhooks
- Implementation of automated invoicing by connecting the weclapp REST API
- Building the frontend using React Router and Shopify App Bridge for native integration
- Design of the database model and implementation of the persistence layer with JPA/Hibernate and Prisma
- Integration of internationalization processes for global use in the frontend and email communication
- Automation of deployment processes using Docker and GitLab CI/CD
Project skills: Java, Spring Boot, Spring Security, Spring Modulith, Hibernate, JPA, REST API, PostgreSQL, Maven, Liquibase, React, TypeScript, React Router, Vite, Node.js, Prisma, Zod, Docker, Docker Compose, GitLab CI/CD, Shopify CLI, Shopify App Bridge, Polaris, weclapp, i18next, Lombok, Vitest
Reginald Leonczuk
AI-Assisted Software Development | IoT | Embedded | Industrial & ERP System Integration
Last position:
ERP System Redesign (web-based)
PHP and React redesign of a web-based ERP system.
- Development of the header and parts of the navigation
- Development of various modules in React, e.g. calendar, chat, and various tables
Frank Doerries
Project management, development and system integration for retrofit on a Uranus thermionic mass spectrometer
Last position:
Project management, development and system integration for retrofit on a Uranus thermionic mass spectrometer at Forschungszentrum Jülich
- Development of a retrofit concept, including qualification measures
- Development, installation and commissioning of the required hardware and software
- Development of a safety concept
- Execution and documentation of in-house verifications / qualification
- Initiation and implementation of measures in case of non-conformities
- Execution of CE conformity assessment procedures and CE marking
Bent-Ove Gütz
OX Administrator
Last position:
KMS system integrator at Soorce Professionals GmbH
- installation and maintenance of communication systems on marine vessels
- advanced security checks
- building cluster environments using VMware ESX servers, DataCore, and Dell hardware
Fabian Jonen
Robotics System Integrator and Web Developer
Last position:
System Integrator for Robotics and Web Development at SENPRO Sensortechnik GmbH
- Developed a collaborative robot cell for automated handling and silicone dispensing of sensor components.
- Responsible for mechanical design, electronics, software integration and final CE certification.
- A custom-designed tool-changing system enabled automated switching between handling and dispensing tools.
- Developed a Django-based control console for industrial robots for process monitoring, combining a real-time dashboard (WebSocket, Chart.js) and a RESTful API (DRF).
- It allows asynchronous program execution, live data and camera stream visualization, robot control, as well as statistical analysis and documentation of process data with an interactive Bootstrap interface.
- Technologies used: Universal Robots (URScript), Arduino, OpenCV, Python, Django/Django REST Framework (DRF), Channels, SQLite, Chart.js, Bootstrap, JavaScript, HTML/CSS, AutoCAD, Autodesk Fusion 360, design & fabrication with aluminum profiles, laser parts, specialized sheet metal, RoboDK simulation
Alban Tchuinkou
C/C++ Developer on AIX Systems for SAP Kernel System Integration
Last position:
C/C++ Developer on AIX Systems for SAP Kernel System Integration at IBM Research and Development
- AIX/Linux system administrator: deployment of LPARs (Logical Partitions) for SAP Kernel Development
- C/C++ SAP kernel development and integration to SAP HANA Database
- C/C++ programming and software integration, support for SAP kernel on AIX system; development and testing on SAP VDI
- Example: development of the ABEC Tool (AIX Build Environment Checker) to create SAP build environments for debugging process and benchmarking
- Benchmarking and test execution of SAP kernels (test from the communication to the SAP HANA Database and to SAP NetWeaver) on AIX
- Automate the SAP kernel build via Jenkins and benchmarking over crontab jobs
- New C/C++ compiler design and testing (based on Clang++ and LLVM)
- Customer ticket handling to resolve SAP kernel bugs and build failures
- SAP kernel development with Rust programming language, migrating some sub-kernel projects from C/C++ to Rust because of Rust's memory safety model, ownership system, and concurrency features
- Refactoring selected components in Rust and integrating them with existing C++ codebase via FFI
Lars Pietrowski
Web and Software Developer (Fullstack) / EDI Interface Developer
Last position:
Interface development
Development of a robust interface for querying ERP data from an SQL database and transferring it to a REST API in JSON format. The interface enables seamless integration of customer order data and ensures efficient data communication between the systems. • Technologies: C#, NET, JSON, MS SQL Server, REST.
Massimiliano Giacometti
Founder and Managing Director, SoC Integration Engineer
Last position:
Founder and Managing Director, SoC Integration Engineer at PlanV
- CVA6 MMU: formal verification using SVA
- CVA6 subsystem: IP integration, verification (UVM)
- Tightly coupled cache coherence for CVA6: RTL design and verification (SystemVerilog), FPGA prototyping (IP integration - CPU, LLC, DDR, Eth), Linux
- Verification of a laser controller on FPGA (medical, VHDL, VUnit, Python, C++ for Microblaze)
- Fault injection emulation on FPGA (SystemVerilog)
Maksym Shvaykovskyy
Head of System Integrations
Last position:
Head of System Integrations at TAKKT AG
- Lead high-performing teams to enhance enterprise system efficiencies, specializing in ERP and PIM systems within AWS, Azure, and proprietary datacenter infrastructures
- Ensure seamless alignment with stakeholder visions through strategic tech integration and dynamic leadership
- Build Generative AI solutions using platforms such as Azure/OpenAI, Google, Claude, and Ollama
- Develop intelligent system integrations and advanced data strategies leveraging AI and machine learning models
- Champion Agile methodologies (SCRUM) and mentor team in roles such as Team Lead, Scrum Master, and Product Owner
- Deliver robust, scalable solutions that power strategic business growth and operational excellence
Adil El Khlifi
AV systems integrator
Last position:
AV systems integrator at Forte Germany GmbH
- SMS-Group full AV systems integration
- Invesco Germany full AV system integration
- SPITZKE SE Central Competence Center full AV system integration
- BP Germany upgraded AV system installation
- And more
Discover over 15,000 top freelancers
Integration Developers statistics
Aggregated from the professional profiles of matched freelancers.
Experience
18 years
Position duration
2 years
Positions per freelancer
15
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Manufacturing, Automotive
Certification focus areas
Information Technology, Production, Business Intelligence
Bachelor's degree or higher
90%
Master's degree or higher
70%
Doctorate
10%
Certifications per freelancer
1
Most common languages
German, English, Polish
Speak two or more languages
100%
Daily Rate Distribution
The chart shows how the daily rates of freelancers in this role 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. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
Average rates for Integration Developers & Seniority distribution
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.
Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
Frequently Asked Questions
Have questions? See our quick guide to FRATCH
An Integration Developer builds the connections between systems so data can move reliably from one application to another. That usually includes API work, message flows, data mapping, transformation, testing, and technical documentation. The role is about keeping business processes connected, not just writing code.
A strong integration developer should understand APIs, middleware, messaging, and data formats like JSON and XML. They should also know how to debug interface errors, handle authentication, and design stable error handling. Good communication matters too, because they often work between business teams and application owners.
An Integration Developer focuses on the interaction between systems and the end-to-end flow of data. An API Developer may work more narrowly on one service, while a Backend Developer often builds core application logic inside a single system. In real projects, the boundaries can overlap, but integration work is usually broader and more cross-system.
A freelance Integration Developer makes sense when you have a defined scope, a deadline, or a temporary skills gap. That is common during migrations, platform rollouts, interface rebuilds, or support for a live project that needs immediate attention. It is often faster than hiring permanently when the need is project-based.
Many projects involve REST, SOAP, OAuth, queues, and file-based exchanges, often with tools such as SAP CPI, MuleSoft, Boomi, Azure Integration Services, or Kafka. The exact stack depends on the system landscape and the type of data exchange. A good freelancer should be able to explain what they used and why.
Much of the Integration Developer work can be done remotely if access, documentation, and test environments are in place. On-site sessions can help at the start of a project, especially when many departments are involved or legacy systems need close coordination. In Germany, a mixed setup is common for enterprise projects.
Ask for examples of past interfaces, failure handling, and how they tested changes before release. A good integration developer can explain trade-offs clearly, show structured debugging habits, and describe how they reduced support issues after go-live. Strong documentation and clean handover are also good signs.
A freelance Integration Developer should be ready to work with unclear source data, changing requirements, and several stakeholders at once. It helps to confirm system access, test data, deployment steps, and ownership early. The best assignments are the ones where technical depth and careful coordination both matter.
The average hourly rate for Integration Developers in Germany is 85 €, which corresponds to a daily rate of about 677 € based on an 8-hour working day.
Of the freelancers working as Integration Developers in Germany, 90% hold at least a Bachelor's degree, 70% hold at least a Master's degree, and 10% hold a doctorate.
On average, freelancers working as Integration Developers in Germany have 18 years of professional experience, with a single engagement typically lasting around 2 years.
The most common languages among freelancers working as Integration Developers in Germany are German (100%), English (100%), and Polish (17%).
The most common industries among freelancers working as Integration Developers in Germany are Information Technology (92%), Manufacturing (83%), and Automotive (50%).
The most common business areas among freelancers working as Integration Developers in Germany are Information Technology (100%), Product Development (92%), and Quality Assurance (75%).
FRATCH Integration Developers main locations
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 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.
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We always have the time for a call or email!
Philipp Thomaschewski
FRATCH CEO
