Contact
Availability
Available part time
20% (approx. 1 day per week)
- •100% Remote (worldwide)
- •On site assignments in the Frankfurt am Main area
- •Willing to travel within Germany (up to 2 days per week)
Certifications
CKAD: Certified Kubernetes Application Developer
The Linux Foundation · February 2027
View Certificate
Security Clearance (SÜ2)
Federal Office for the Protection of the Constitution · March 2028
Education
- 09/2008 – 02/2013
HfT Stuttgart
B.Sc. Business Information Systems
- 09/2006 – 09/2008
University of Stuttgart
Diploma in Computer Science (discontinued)
- 09/2000 – 09/2004
Adem Tolunay Gymnasium (Antalya)
General Higher Education Entrance Qualification (Abitur)
Language
German
Fluent
English
Conversational
Turkish
Native
M.Ilker Yildirim
Software & Cloud Engineer
Professional Profile
With over a decade of experience as an independent freelance Software and Cloud Engineer, I specialize in building backend heavy IT systems. My core focus lies in Java based Microservices, Cloud Native architectures, and secure Identity and Access Management (IAM) solutions.
Rather than relying on theoretical buzzwords, I deliver pragmatic and highly performant architectures. Whether migrating complex legacy systems to the cloud, implementing event driven microservices, or orchestrating deployments with Docker and Kubernetes. I write clean code and build resilient systems.
Your Advantage: As an independent freelance consultant, I offer transparent and legally compliant project collaboration. Furthermore, my active security clearance (SÜ2) makes me a highly trusted partner for critical projects in the public sector and finance.
How I can help you
Backend Development
I build backend systems designed to perform under heavy load. Utilizing Java (Spring Boot, Quarkus), Apache Kafka, and proven resilience patterns, I decouple complex monoliths into future proof microservice architectures.
CI / CD
By implementing fully automated CI/CD pipelines, I accelerate your development cycles, increase software quality, and minimize deployment risk. Your team becomes more productive, and your releases become more reliable.
Kubernetes / Docker
With Docker, I containerize your applications and make them portable. Through orchestration with Kubernetes, I ensure maximum scalability, high fault tolerance, and efficient resource utilization — the foundation of a modern microservice architecture.
Cloud & Cloud-Native
I design and implement cloud-native architectures built from the ground up for the cloud. The result is highly flexible, cost-efficient, and resilient systems that grow with your company's requirements.
Access & Identity Management
Security is not an afterthought. I implement custom IAM solutions, specializing in OpenID protocols. I seamlessly integrate external Identity Providers to secure your distributed services.
Frontend Development
My core expertise is in the backend, but I do not work in silos. I seamlessly integrate APIs, pragmatically extend existing UI services (like Angular), and ensure smooth collaboration across engineering teams.
Work Experience / Projects
Over a decade of experience in backend development and cloud transformation
- 07/2025 – present
ITZ Bund / Materna GmbH
Software Engineer (Freelancer)
More information and details coming soon.
Based in Frankfurt am Main - 03/2025 – present
Algebra Engineering & Consulting GmbH
Software Engineer (Freelancer, part-time)
Migration of a monolithic custom HR management software into a cloud-native microservices architecture
- Analyzed and progressively split an existing monolith into independent, domain-specific microservices
- Developed services with Java, Spring Boot, and JPA/Hibernate following Domain-Driven Design principles
- Introduced distributed transaction management based on the SAGA pattern
- Implemented asynchronous communication between services with Apache Kafka to enable decoupled, event-based data exchange
- Implemented resilience patterns (retry, timeout, circuit breaker) with Resilience4j to increase fault tolerance and stability of the microservice landscape
- Deployed containerized microservices on a Kubernetes cluster (K3s), including Helm-based configuration
- Integrated OpenTelemetry for distributed tracing and metrics, using Zipkin as the tracing backend to analyze service communication and performance
- Built and maintained GitLab CI/CD pipelines to automate build, test, and deployment processes, including static code analysis with SonarQube and artifact management with Nexus
- Created and maintained RESTful APIs including specification with OpenAPI/Swagger
- Set up monitoring and visualization with Prometheus Operator and Grafana
JavaSpring BootHibernate/JPAMicroservicesRESTfulKafkaSAGA PatternResilience4jOpenTelemetryZipkinDockerKubernetesK3sHelmPostgreSQLGitLab CI/CDMavenGitOpenAPI/SwaggerSonarQubeNexusPrometheusGrafanaKanbanBased in Stuttgart - 07/2023 – 01/2025
Mercedes-Benz / Netgo GmbH
Software Engineer (Freelancer)
Maintenance and further development of BPMN process-based business applications, plus cloud transformation of the services
- Further developed and maintained backend services based on Spring Boot, focusing on performance and scalability
- Modeled, extended, and maintained existing business processes using Camunda
- Set up and maintained CI/CD pipelines with Jenkins and GitLab CI to ensure efficient development and delivery processes
- Automated database backup and rollback operations through custom pipeline solutions
- Developed strategies for the cloud-native transformation of existing systems
- Planned and executed the migration of backend and frontend services from on-premise servers to Kubernetes
- Developed and maintained user interfaces with Form.IO, integrated into BPMN processes
- Analyzed and integrated new technologies into existing projects, including building prototypes to evaluate feasibility
- Conducted preliminary analyses and prepared the migration of services from Kubernetes to AWS
- Integrated Keycloak as a proxy provider for central management of authentication and authorization processes
- Developed custom Keycloak modules to enable integration of third-party LDAP and OIDC providers
- Adapted and extended Keycloak functionality to meet specific identity management and access control requirements
JavaSpring BootSpring SecuritySpring CloudSpring DataHibernateAngularCamundaForm.ioKubernetesDockerHelmAWSKafkaKeycloakPostgreSQLMS SQLJenkinsGitLab CILiquibaseOpenID/OAuth2MavenJiraConfluenceSonarQubeGitHub ActionsBlackduckBased in Berlin - 06/2023 – 07/2023
Messe München / Questit
Solution Architect (Freelancer)
Audit evaluating optimization and refactoring options and assessing the cloud migration of the existing CMS system
- Actively participated in technical meetings with stakeholders to align on requirements and solution strategies
- Analyzed existing CMS systems to identify optimization potential in templates and modules and implemented improvements
- Evaluated feasibility and prepared CMS systems for cloud transformation, taking technical and business requirements into account
- Implemented cloud transformation strategies focused on improved system performance, scalability, and cost efficiency
- Worked closely with customers and stakeholders to clarify requirements and ensure a smooth transformation process
- Conducted stakeholder interviews to clarify goals and define a sustainable cloud transformation strategy
- Interviewed software vendors to assess the capabilities and limitations of cloud environments and derive suitable implementation approaches
FirstSpirit 5.x (Cloud)JavaCMS TemplatingAzureDockerNextJSBambooJiraConfluencePostgreSQLBased in Munich - 08/2022 – 06/2023
Federal Office for Economic Affairs and Export Control (BAFA) / Adesso SE
Senior Full Stack Developer
Further development and maintenance of funding procedure applications
- Developed and optimized backend services using Spring Boot
- Ensured data security and compliance when transferring sensitive form data
- Maintained and further developed a Swing-based desktop application, focusing on stability and integration of new features
- Optimized the existing codebase to improve maintainability and performance of the legacy application
- Optimized data processing to ensure efficient and reliable handling of form data within the backend services
- Integrated and managed Oracle databases, including query performance optimization
- Built RESTful APIs to ensure efficient communication between frontend and backend
- Built and maintained CI/CD pipelines for automated application deployment
- Analyzed and fixed bugs and performance issues across the entire technology stack
- Evaluated and integrated new technologies to improve application performance and maintainability
- Documented systems and processes to improve transparency and traceability for future development
JavaSpringSwingAngularJSFJUnitSOAPRTFCIBMavenSVNWildFlyEclipseVS CodeOracle SQL DeveloperTeamCityJiraConfluenceOracle DBMySQLLiquibaseHibernateBased in Eschborn - 01/2022 – 08/2022
BMW / Adesso SE
Senior Full Stack Developer
Development of a central platform for providing and managing EMS and WLTP data for connected systems
- Led the development team as deputy tech lead, responsible for technical decision-making and team coordination
- Developed a central service for managing and providing EMS and WLTP data for connected applications and services, based on Java EE and Spring
- Migrated the on-premise Oracle database to AWS RDS PostgreSQL, including adapting database structures and optimizing queries for the new environment
- Deployed and orchestrated the application in Kubernetes environments (AWS EKS and OpenShift) using Helm and Docker
- Built and maintained CI/CD pipelines to automate builds, tests, and deployments
- Introduced and managed authentication and authorization mechanisms using OpenID Connect and OAuth
- Monitored the performance and reliability of the central service with AWS CloudWatch, including analyzing and resolving production issues
- Conducted unit, integration, and load testing with JUnit
- Worked closely with internal teams and stakeholders to align requirements and ensure successful integration of connected systems
- Analyzed, evaluated, and integrated new technologies and best practices to continuously improve the scalability and efficiency of the central service
Java EESpringSwingAngularJUnitRESTSOAPOracle DBHibernateAWSFlywayOpenShiftMavenGlassfishKubernetesDockerHelmOpenID/OAuth2JenkinsBased in Munich - 01/2021 – 11/2021
Mercedes-Benz / Material.one / Adesso SE
Senior Full Stack Developer
Development and integration of a service for secure transfer and approval of sampling data between Mercedes-Benz and its suppliers
- Further developed and optimized sampling data management services with Java, Spring Boot, and related Spring modules such as Spring Security, Spring Batch, and Spring Data
- Implemented both client-side and server-side encryption of sampling data using HashiCorp Vault, storing encrypted data in MinIO via S3 API calls
- Integrated Azure IAM as an external identity provider into Keycloak, allowing both local Keycloak users and Azure IAM users to access the application
- Implemented and maintained database migrations with Liquibase
- Managed and optimized databases (MS SQL, PostgreSQL) and implemented efficient data queries to improve system performance
- Orchestrated and deployed the application in Docker and Kubernetes environments
- Built CI/CD pipelines with Jenkins to automate the development and deployment process
- Worked closely with internal teams to integrate the software into company-wide systems and align requirements with stakeholders
- Analyzed and integrated new technologies to improve software efficiency and flexibility, particularly in encryption, storage, and cloud integration
JavaSpring BootSpring SecuritySpring BatchSpring DataMS SQLMicrosoft AzureDockerKubernetesJenkinsLombokEtcdHashiCorp VaultPostgreSQLMinIOLiquibaseBased in Stuttgart - 02/2020 – 01/2021
Mercedes-Benz / Adesso SE
Senior Full Stack Developer / Tech Lead
Development of a content management system for After-Sales Operations
- Led the development team as tech lead, responsible for technical decision-making and team coordination
- Communicated between stakeholders and the development team to clarify requirements, present progress, and align on technical solutions
- Planned and negotiated the project budget with clients, including resource alignment and cost optimization
- Developed and integrated a content management system (CMS) with FirstSpirit, tailored to the requirements of Mercedes-Benz After-Sales Operations
- Designed and developed REST APIs and backend services with Spring Boot and Spring Data to support CMS functionality
- Built and maintained the user interface with Angular, Bootstrap, HTML, CSS, and JavaScript
- Orchestrated and deployed the application in Kubernetes environments on IBM Cloud, using Docker for containerization
- Automated build and deployment processes with Jenkins to ensure continuous integration and delivery
- Worked closely with internal and external teams to integrate the CMS into existing company systems and processes
JavaSpring BootSpring DataFirstSpiritIBM CloudKubernetesDockerElasticsearchJenkinsMongoDBHTMLCSSJavaScriptBootstrapGradleRESTGitAngularBased in Stuttgart - 06/2018 – 02/2020
Daimler Fleetboard GmbH / Adesso SE
Senior Full Stack Developer
Development of a central access and identity management system for fleet management services
- Designed and developed a central access and identity management system using Azure AD B2C, ensuring consistent and secure authentication and authorization across all fleet management services
- Implemented OAuth2-based security mechanisms and integrated the central IAM with connected services
- Developed microservices with Spring Boot, Spring Security, and Spring Data, including REST APIs for data exchange between services
- Deployed and orchestrated services in Azure Kubernetes Service (AKS) with Helm and Docker
- Set up CI/CD with Azure DevOps, including code quality monitoring with SonarQube and performance monitoring with Grafana
- Worked closely and coordinated regularly with teams from other services to ensure interoperability and consistency between components
- Presented project progress and technical solutions to stakeholders from various regions worldwide to align on and secure requirements
- Continuously coordinated with the legal department to ensure compliance with data protection requirements, particularly regarding regional and global regulations
- Conducted code reviews and ensured adherence to best practices within the team
JavaSpring BootSpring SecuritySpring DataMicroservicesAngularJavaScriptMicrosoft AzureKubernetesHelmDockerGrafanaSonarQubeOAuth2GitJiraConfluenceBased in Stuttgart - 10/2016 – 06/2018
KfW Bank / Adesso SE
Senior Java – CMS Developer
Development and implementation of the content management system for the KfW Bank website
- Designed and implemented a content management system (CMS) with FirstSpirit 5, including developing Java-based modules to meet KfW Bank's specific requirements
- Designed and implemented an integrated content management and publishing workflow, including a four-eyes principle for editors, to make approval processes efficient and secure
- Developed workflow logic and extensions as Java-based extensions, including integration into the FirstSpirit CMS
- Customized and developed CMS templates with Java, HTML, CSS, and jQuery
- Worked closely with the UI/UX design team to technically implement design specifications
- Integrated the provided UI/UX designs into the CMS, taking performance and scalability into account
- Managed and optimized the database (DB2), including developing efficient queries to support CMS functionality
- Ensured system stability through regular testing, debugging, and performance optimization
- Documented technical implementations and handed them over to internal teams for further maintenance and training
- Conducted code reviews and ensured adherence to best practices
JavaJavaScriptDB2FirstSpirit 5SpringHTMLCMS TemplatingTomcatCSSjQueryBased in Frankfurt am Main - 05/2016 – 10/2016
Wilo SE / Adesso SE
Java – CMS Developer
Implementation of a content management system with FirstSpirit for the Wilo SE web presence
- Developed and customized the FirstSpirit CMS through Java-based modules to meet the specific requirements of Wilo SE's web presence
- Integrated analytics systems such as Customer Analytics and Real-Time Targeting into the CMS to capture and analyze user data for targeted marketing and communication strategies
- Created and customized templates with JavaScript, HTML, and CSS
- Implemented REST APIs to enable and optimize communication between the CMS and external systems
- Optimized CMS performance through adjustments and extensions based on customer requirements
- Ensured compatibility of templates and modules across various browsers and devices
JavaFirstSpiritRESTJavaScriptHTMLCSSUniversal MessengerCustomer AnalyticsReal-Time TargetingBased in Dortmund - 10/2013 – 05/2016
Daimler AG / Adesso SE
Java – CMS Developer
Implementation of a FirstSpirit CMS for the After Sales Operations website
- Designed and implemented a content management system (CMS) with FirstSpirit to support the Daimler AG After Sales Operations website
- Developed and customized templates with JSP, HTML, CSS, JavaScript, and jQuery
- Developed Java-based modules to extend and optimize CMS functionality, tailored to the project's specific requirements
- Designed and implemented complex workflow designs for approval and publishing processes, including four-eyes or six-eyes principles, to ensure quality assurance and compliance
- Documented workflows, modules, and technical implementations to support future maintenance and extension of the system
JavaFirstSpiritJSPHTMLCSSJavaScriptjQueryMavenSVNOracle DBBased in Stuttgart - 09/2011 – 02/2013
Porsche AG
Student Assistant / Bachelor's Thesis
Implementation of software for evaluating returned lease vehicles
Based in Stuttgart