07.10.2026 aktualisiert
100 % verfügbar
Senior Software Developer
Steinhagen, Deutschland
Weltweit
IT specialist in software developmentÜber mich
Motivated software developer with over a decade of experience, passionate about embracing new challenges and continuously expanding my skills. Flexible and open-minded, I’m dedicated to delivering excellent results—whether working independently or collaborating with a team.
Skills
PHPAPIsAuthenticationsSaasDatenbank DesignLinuxPerformance ManagementLinux-AdministrationMySQLLeistungssteigerungSoftware ArchitectureSoftwareentwicklungSymfonyWeb Performance OptimizationWorkflows
Senior PHP & Symfony Backend Development
Senior-level PHP and Symfony development for complex backend systems, business applications, APIs, and long-running production platforms.
Backend Architecture & REST APIs
Design of maintainable backend architectures, REST APIs, service boundaries, authentication, authorization, integrations, and asynchronous workflows.
Legacy PHP & Symfony Modernization
Modernization of existing PHP and Symfony applications, including technical debt reduction, refactoring, upgrades, testing, architecture improvements, and safe incremental migration.
Database Design & Performance
SQL database design, Doctrine ORM, query optimization, indexing, transaction boundaries, data integrity, and performance analysis for backend applications.
SaaS, Multi-Tenancy & Microservices
Architecture and development of SaaS platforms, multi-tenant systems, microservices, messaging, background processing, and service integrations.
Performance & Reliability Engineering
Analysis and improvement of slow, unstable, or difficult-to-operate backend systems, including caching, database bottlenecks, concurrency, workers, resource limits, and production failures.
Docker, CI/CD & Production Delivery
Docker-based environments, CI/CD pipelines, deployment workflows, worker processes, configuration management, observability, and production-readiness improvements.
Security-Focused Backend Engineering
Authentication, authorization, tenant isolation, secure APIs, sensitive-data handling, background-job security, and security-conscious backend architecture.
Testing & Code Quality
PHPUnit, integration testing, characterization tests, static analysis, automated quality checks, and test strategies for both legacy and modern applications.
Linux & Server Environments
Linux administration, Bash scripting, PHP-FPM, runtime configuration, networking, filesystem permissions, production troubleshooting, and server diagnostics.
AWS & Cloud Environments
AWS fundamentals, cloud deployments, Docker-based workloads, infrastructure integration, application configuration, and secure backend delivery.
Erfahrung
Berufserfahrungmehr als 10 Jahre
Freelancer seit2009
Sprachen
DeutschverhandlungssicherEnglischverhandlungssicher
Projekthistorie
Delivered websites, web applications, and custom software for international clients.
Provided technical support and troubleshooting.
Nine years building enterprise backend systems and scalable web applications.
- Designed and implemented REST APIs and microservice architectures
- Backend architecture and technical design; contributed to architecture decisions and engineering standards
- Database design and optimization
- Authentication and authorization
- Automated testing with PHPUnit
- Docker-based development and deployment; built and automated CI/CD pipelines
- Hands-on work with Kubernetes-based containerized environments
- Collaborated with infrastructure and frontend engineering teams
Developed and maintained web applications and internal business systems.
Implemented backend and frontend features, and supported deployment and system maintena