Spring Boot Experts in Cologne
matched in minutes from over 15,000 CVsHire experts who create secure REST APIs, modular Java services and cloud-ready applications with Spring Boot, Spring Security and Spring Data. FRATCH matches you quickly and precisely with vetted, available freelancers.
Meet FRATCH Experts in Cologne, who have recently used Spring Boot
Hooman B.
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.
Burhan D.
Last position:
Enterprise Architect & Solution Architect at DB Netz AG
With project PRIZMA, DB will modernize its infrastructure on the one hand, and develop a fail-safe IT landscape on the other hand, which can be restored quickly and securely in case of a disaster.
- Capture current architectures of existing systems as well as methodical consulting and development of target architectures
- Deepen and maintain the building plan / target IT landscape
- Implement technical architecture concepts & architecture descriptions
- Implement migration concepts for updating and further developing the platform and information systems
- Assess submitted improvement suggestions as part of the project
- Capability management: identify capability gaps, develop target visions, and support transformation planning within the enterprise architecture.
- Create a compatibility matrix of the components in use and compare dependencies of specific versions
- Create an IT concept for extending the platform with the following topics: hardware and software requirements, security, licensing, high availability, load balancing, backup & recovery, update strategy, monitoring integration, etc.
- Coordinate with business architects as well as technical architects from the cross-functional architecture area of the PRISMA program for the topics (backup, Active Directory, monitoring, Citrix, and business applications ...)
- Status meetings and alignment of project planning with the Release Train Engineer / Project Manager
- Advise the Release Train Engineer / Project Manager in identifying project risks
- Advise the System Architect Engineers in steering the implementation of the concept
- Implement the IT concept
- Document the infrastructure
Label: MS Project, LINUX, Windows, ORACLE, Java, REST, SharePoint, Microsoft Exchange, UML, Enterprise Architect, BPMN, AZURE, AWS, V-MODEL, Micro Service, VisualStudio, SAP S/4HANA, SCRUM(SAFE), ESB (TIBCO), Python, Innovator, LeanIX (TOGAF), Ansible, Ansible Tower, Ansible Automation, ROBOT, SpringBoot
Marc S.
Last position:
Fullstack Developer at PLANT-MY-TREE
PLANT-MY-TREE®-per-order
The application enables Shopify merchants to automatically place tree-planting orders for every incoming order. By integrating ecological contributions directly into the purchase process, the manual effort 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 to capture order data in an event-driven way and integrates the weclapp ERP system 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 via 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 25, 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
Maurice K.
Last position:
Solution Architect – Cloud-Native Transformation of IoT Monitoring Platform at NDA / Wind Energy Sector
- Led the end-to-end architecture and migration of a legacy on- premise IoT monitoring system to a cloud-native Azure platform within a 17-member development team
- Designed and implemented a scalable microservices architecture (Java 21, Spring Boot, Kubernetes, Azure Services), decoupling IoT data streams and eliminating legacy system bottlenecks
- Defined technology stack, mentored developers, and orchestrated cross-functional teams in 4 countries to ensure high-quality delivery and alignment with architectural standards
- Drove requirements engineering and system redesign, removing years of technical debt and introducing event-driven processing and automated workflows
- Key Achievements
- Increased system stability and uptime by ~10x, eliminating need for 24/7 DevOps intervention
- Reduced hosting costs by ~80% (5x savings) through cloud optimization
- Improved performance and scalability, enabling stable handling of high-volume IoT data streams
- Delivered successful zero-disruption migration from on-prem to cloud, with strong user satisfaction and reliability from day one
Nawfal C.
Last position:
Internship in Software Development at Haeger Consulting
- working in a team using an agile method (Scrum)
- Backend development in Java (Spring Boot)
- Frontend development in Angular
Thomas P.
Last position:
Freelance Software Architect at Self-employed
Allal K.
Last position:
Java Senior Full Stack Developer at Insurance ÖRAG
- Further development of a policy administration system (contract/claims) for the legal expenses insurer ÖRAG.
- My role: Senior Software Developer.
- The team consists of 12 developers.
- Technologies used: Java 8/21, Java EE, Quarkus, WebLogic, JPA, RabbitMQ, JTA, CI, CD, Jenkins, DB2, Maven, Jenkins, GIT (bitbucket) later GitLab, Junit, Elasticsearch, Mockito, Jira, SonarQube, Scrum, React, Workflow
- Migration and modernization of legacy systems: rewrote C and C++ code in Java to improve maintainability, scalability, and performance. Refactored Python into Java, including optimization and integration into modern architectures.
- Study on the use of AI (Codex) for implementing a Java feature. The goal is to compare the time spent and productivity of AI-supported development with a classic implementation by a developer. The results should show how strongly the use of AI affects development time and efficiency.
- Development of the following tariff calculators for the years 2024/2026: private, companies, doctors, farmers, owner-occupied G + H, landlords, traffic, club, top managers, sales representatives, special criminal law, savings bank, municipal, BayGT, doctors, Dehoga
Hamdi R.
Last position:
Full-Stack AI Developer at Karray-Pflege GmbH
PFS-Matching-App
- Integrated an intelligent LLM chatbot using LangChain4j, enabling conversational AI, context-aware question answering, document summarization, and autonomous tool execution.
- Implemented Retrieval-Augmented Generation (RAG), prompt engineering, and AI agent workflows to connect large language models with enterprise data and backend services.
- Developed RESTful APIs and secure backend services to support AI-driven interactions and business processes
Markus G.
Last position:
Full Stack Developer at REWE Digital
- A warehouse valuation system was reimplemented using Java, Spring Boot, and Camunda. The backend solution focuses on integration and batch calculations, the frontend on managing formulas and reviewing results.
- Java 21
- Spring Boot
- JPA
- Maven
- REST
- Kafka
- PostgreSQL
- DB2
- Liquibase
- Google Cloud Storage
- Keycloak
- GitLab CI/CD
- Helm
- Terragrunt
- SonarQube
- Angular
- IntelliJ
- JUnit 5
- Mockito
- Open API
Jens H.
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
Ayhan G.
Last position:
Senior QA Engineer / Test Automation Engineer / SDET at Rewe digital
Consulting, designing, and implementing the software testing lifecycle for multiple Android apps and backends Introducing test automation with Appium, SpringBootTest, RestAssured Setting up and managing emulators Developing an E2E library, an integration library, a Testcontainers library, and other libraries Developing, implementing, and advising on CI strategies Building the test environment with Testcontainers and virtualization Developing and implementing test cases for integration tests and end-to-end tests Establishing a maintainable test architecture with low entry barriers to simplify the creation of automated tests Some tools and technologies used: JUnit, RestAssured, Testcontainers, Kubedock, Appium, Android emulator, Jira Xray, Mockito, WireMock, Spring Framework, Kotlin
Predrag P.
Last position:
Test Developer | Test Automator at CreditReform
Technologies: Java 25, Selenium, Insomnia, SSO, GitLab, Jenkins, Docker, Kubernetes, Jira, IntelliJ, Nexus, Oracle, MariaDB, Spring Boot, Grafana, Concept Board, Vue.js, OpenAPI, Kotlin. Implementation, maintenance, and extension of automated end-to-end regression tests for UI and API interfaces. Appropriate and targeted test automation across multiple software products, including Java-based Windows applications. Automating business processes with Selenium, reset jobs, and DB import jobs, as well as creating test concepts, test case descriptions, and structured bug reporting.
Vladimir M.
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 N.
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
Jyothikrishna S.
Last position:
Senior Back-end Engineer at RLE Engineering and Services GmbH
- Works at Ford Motor Company as Senior Back-end Developer on contract via outsourcing
- Designed and developed REST APIs based on the analyzed requirements and technical standards
- Investigated issues and defects to determine root causes and formulate corrective action measures
- Participated in QA, stage, and production release activities
- Conducted code reviews for performance improvement
- Provided monitoring and support using GCP
- Used test driven and behaviour driven development approaches
- Took part in agile ceremonies
Discover over 15,000 top freelancers
Statistics of experts using Spring Boot
Aggregated from the professional profiles of matched freelancers.
Experience
19 years (Germany: 17 years)
Position duration
2 years (Germany: 1.9 years)
Positions per freelancer
13 (Germany: 12)
Top business areas
Information Technology, Product Development, Quality Assurance
Top industries
Information Technology, Retail, Banking and Finance
Certification focus areas
Information Technology, Product Development, Project Management
Bachelor's degree or higher
95%
Master's degree or higher
71% (Germany: 55%)
Doctorate
10% (Germany: 6%)
Certifications per freelancer
2
Most common languages
German, English, French
Speak two or more languages
100% (Germany: 96%)
Based on our profile pool as of 19 Sep 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 Spring Boot
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 19 Sep 2026. Actual rates may vary depending on seniority level, experience, skill specialization, project complexity, and engagement length.
Spring Boot 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 (96%)
- Retail (50%)
- Banking and Finance (46%)
- Automotive (42%)
- Telecommunication (42%)
- Transportation (38%)
- Government and Administration (38%)
- Insurance (33%)
Please note that freelancers can work across multiple industries, so percentages overlap.
About the technology
Spring Boot foundations
Spring Boot is an open-source framework for building production-ready applications with Java and the wider Spring ecosystem. It reduces configuration through auto-configuration, starter dependencies and embedded servers, while keeping application structure explicit and testable. It is widely used for REST services, web applications, batch processes and backend systems.
Services and systems
Spring Boot supports modular monoliths and distributed services that connect business processes, data stores and external APIs. Professionals use it for payment flows, customer portals, logistics services, industrial systems and internal business applications. Its strong integration with Java makes it suitable for long-lived systems that need clear ownership and maintainable code.
Ecosystem and tooling
The framework works closely with Spring MVC, Spring WebFlux, Spring Security, Spring Data and Spring Cloud. A capable specialist may also bring experience with:
- JPA, Hibernate and relational databases
- Kafka, messaging and scheduled processing
- Docker, Kubernetes and cloud deployment
- Maven or Gradle, Git and automated testing
When expertise matters
Companies often bring in freelance specialists when a Java service needs a reliable foundation, a legacy Spring application requires modernization or an API must connect safely to new systems. Cologne-based teams may benefit from on-site workshops, while remote collaboration works well for focused delivery when communication, documentation and access are organized.
Delivery and security
Strong Spring Boot professionals define clear boundaries between controllers, services and data access. They handle configuration by environment, validation, error responses, logging and observability rather than treating them as afterthoughts. They also understand authentication and authorization with Spring Security, secure dependency management and practical integration testing.
Choosing a specialist
Look for evidence of comparable Spring Boot systems, not familiarity with the framework name alone. A useful professional can explain trade-offs between Spring MVC and WebFlux, select suitable persistence patterns and improve an existing codebase without unnecessary rewrites. Ask for examples of testing, deployment, incident handling and collaboration with product and operations teams.
Frequently asked questions
Everything clients usually want to know about Spring Boot, in one place.
Spring Boot is used to create Java web applications, REST APIs, background services and business systems. It provides sensible defaults and integrated tooling so teams can focus on application behavior while retaining control over configuration and architecture.
Spring Boot has a broad ecosystem, extensive documentation and strong adoption across enterprise Java. Quarkus and Micronaut can offer a leaner runtime profile or faster startup in some cloud and native deployments, so the right choice depends on existing skills, libraries, operational goals and the application's workload.
A strong Spring Boot specialist usually understands Java, HTTP, SQL and API design alongside Spring MVC, Spring Security and Spring Data. Experience with Docker, Kubernetes, cloud services, messaging systems and automated testing is also valuable when the work reaches production.
The needed experience depends on the system's risk, integrations and delivery stage. A small API may need focused framework knowledge, while a regulated or distributed system calls for a professional who can shape architecture, security, observability, testing and release practices.
Yes. Spring Boot projects are well suited to remote collaboration when repositories, environments, tickets and deployment processes are accessible. Cologne teams should agree early on working hours, workshop needs, documentation standards and whether German or English is required for communication.
Spring Boot is a strong fit when a team wants a Java backend with established integrations, clear conventions and room to grow. It is especially useful for systems that need security, database access, messaging, transaction handling and reliable operational support.
Ask how the professional would structure modules, test integrations, manage configuration and protect sensitive endpoints. A capable Spring Boot expert explains trade-offs clearly, reviews existing code constructively and connects technical decisions to reliability, delivery and maintenance.
Teams in Cologne may work across product, operations and enterprise IT environments, so clear technical communication matters. Spring Boot professionals should be ready to align on architecture, contribute to code reviews, document decisions and collaborate either on-site or remotely according to the project setup.
The average hourly rate of freelancers in Cologne, Germany who have used Spring Boot in their recent projects is 93 €, which corresponds to a daily rate of about 742 € based on an 8-hour working day.
Of the freelancers in Cologne, Germany who have used Spring Boot in their recent projects, 95% hold at least a Bachelor's degree, 71% hold at least a Master's degree, and 10% hold a doctorate.
On average, freelancers in Cologne, Germany who have used Spring Boot in their recent projects have 19 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 Spring Boot in their recent projects are German (100%), English (100%), and French (38%).
The most common industries among freelancers in Cologne, Germany who have used Spring Boot in their recent projects are Information Technology (96%), Retail (50%), and Banking and Finance (46%).
The most common business areas among freelancers in Cologne, Germany who have used Spring Boot in their recent projects are Information Technology (100%), Product Development (88%), and Quality Assurance (63%).
Main locations of FRATCH Experts, who have recently used Spring Boot
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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