Senior / Mid Backend Engineer

Zixio develops software for complex, business-critical processes in pharma, clinical trials, medicine and industry. Our systems are used in real operational environments where stability, security, traceability and maintainability matter.

We are a technology-driven team based in Berlin. We are looking for a Senior or strong Mid-Level Backend Engineer who solves problems independently, challenges technical decisions constructively and strengthens our engineering team.

What you will work on

You will mainly work on backend systems for complex B2B applications. Depending on the project, you will also be involved in architecture, data modelling, API design, deployments, testing, security topics and technical documentation.

Typical topics include:

• backend development with PHP and relational databases
• roles, permissions, workflows and business logic
• API integrations and interfaces to external systems
• architecture discussions with our CTO and project team
• automated tests, debugging and quality assurance
• deployment and operational topics
• security aspects around data, authentication and interfaces
• AI integrations, such as internal AI hubs or assistant systems

We care about speed, but not at the expense of structure, quality and maintainability., * hybrid work and flexible working hours

• budget for training, conferences, certifications or coaching
• room to shape technical topics and take responsibility
• challenging projects instead of generic websites
• work on systems that are actually used in production
• close involvement in architecture and product decisions

Our engineering culture and stance on AI

We are building a solid, ambitious engineering team. We care deeply about technical quality: architecture, maintainability, security, testing, documentation and stable operation.

We also want our developers to keep growing. That means learning time, training budget, conferences, certifications and active support for technical development are part of how we work. We want people to stay close to new technologies and to have the space to become better engineers over time.

We have worked with AI technologies since 2017 and understand them beyond ready-to-use tools. We see AI as a way to empower engineers, not replace them. We follow current research, test new approaches critically and apply AI where it creates real value: internally in our own workflows and externally in customer systems. We are looking for someone who shares this mindset: curious about new technologies, but grounded enough to use them responsibly.

Leistungen:

• Betriebliche Weiterbildung
• Flexible Arbeitszeiten
• Gleitzeit
• Homeoffice-Möglichkeit
• Kostenlose Getränke
• Sabbatical

Requirements

Do you have experience in PHP?, * have several years of backend development experience, ideally with PHP and a common framework

• work confidently with relational databases and APIs
• understand design patterns, clean architecture and maintainable code
• analyze problems systematically instead of only fixing symptoms
• take web application security seriously
• enjoy learning new technologies and technical concepts
• like discussing technical decisions constructively
• work independently, take ownership and collaborate well with a team

We are looking for someone who genuinely enjoys technology and wants to understand how systems can be improved.

Nice to have

• Yii2, Laravel, Symfony or similar PHP frameworks
• experience with complex B2B or long-running business applications
• experience in regulated environments such as pharma, medicine, GxP, ISO or data protection
• understanding of OWASP, logging, audit trails, roles and permission concepts
• experience with automated testing, Docker, Linux, CI/CD or deployments
• interest in AI integration, LLMs, RAG or automation
• basic HTML, CSS and JavaScript skills

Benefits & conditions

Pulled from the full job description

• Flextime
• Sabbatical
• Work from home
• Flexible schedule