About the opportunity

Our client is an international technology company operating in the cybersecurity and software security space. Its engineering teams develop and maintain a security-focused platform used by organizations across multiple markets.

The company places strong emphasis on software quality, privacy, open-source principles and robust security architecture. You will join a collaborative engineering environment where technical autonomy, thoughtful design and continuous improvement are encouraged.

The role

We are looking for a Backend Software Engineer to contribute to the development and evolution of several software offerings, including self-hosted and cloud-based solutions.

Working within the backend team, you will develop and maintain APIs, implement business logic, strengthen application security and ensure the reliability and performance of existing services. The position involves the full development lifecycle, from technical analysis and implementation to testing, deployment support and continuous improvement.

You will also contribute to architectural discussions and help translate functional requirements into maintainable, secure and scalable solutions.

Key responsibilities

Backend development and quality

Design, develop and maintain backend features using PHP and CakePHP.
Improve existing code, investigate defects and deliver corrective fixes.
Translate functional specifications into reliable API workflows while preserving backward compatibility.
Participate in peer code reviews and apply consistent engineering standards.
Develop and maintain unit tests, targeting approximately 80% code coverage.
Implement end-to-end tests covering critical user journeys.
Optimize performance, scalability and compatibility across environments.
Favor clear, maintainable solutions and avoid unnecessary complexity.

Technical analysis and documentation

Help analyze customer feedback, bug reports and feature requests.
Work with product stakeholders to define appropriate technical and functional approaches.
Identify opportunities for structural and architectural improvements.
Maintain technical documentation, including OpenAPI specifications, SDK documentation and user or administrator guides.
Share technical knowledge through internal documentation and presentations.

Delivery and reliability

Support release preparation and deployment activities.
Collaborate with Site Reliability Engineering (SRE) teams on CI/CD pipelines and release quality.
Investigate production incidents and contribute to service restoration.
Participate in blameless post-incident reviews, root-cause analysis and corrective actions.

Security and data protection

Assess security risks associated with proposed changes and identify suitable mitigations.
Apply secure coding practices and established security standards.
Monitor dependencies for vulnerabilities and implement fixes without introducing regressions.
Support compliance with GDPR and applicable data protection requirements.
Contribute to security policies, risk management, least-privilege access and segregation of duties.
Participate in security exercises and continuous improvement of incident-management procedures.

Team collaboration

Manage priorities, deadlines and individual deliverables autonomously.
Communicate progress, risks and technical decisions proactively.
Contribute to pair programming, peer support and knowledge sharing.

Required technical background

A degree in Computer Science, Software Engineering, Electronics or a related field, or equivalent professional experience and qualifications.
At least 3 years of experience developing PHP applications.
Strong backend development skills with CakePHP, Laravel or Symfony.
Practical experience testing applications with PHPUnit.
Familiarity with OpenAPI specifications.
Good knowledge of Git and branching strategies.
Strong understanding of OWASP Top 10 vulnerabilities and secure coding principles.
Proficiency in at least one additional programming language, such as JavaScript, Bash, Python, Go or Rust.
Professional fluency in English, written and spoken.

Additional assets

Experience in one or more of the following areas would be advantageous:

Large-scale, high-availability software systems.
End-to-end testing or performance testing.
Evolutionary database design.
Authentication technologies such as OAuth, JWT, WebAuthn, Duo or Yubico.
Directory services and identity integrations, including LDAP, Active Directory or SCIM.
UML documentation.
Maintaining a mature, long-lived codebase.
Contributing to open-source projects.
Working with distributed teams and asynchronous communication.
Writing technical articles, blog posts or delivering technical presentations.

Personal qualities

Strong analytical and problem-solving skills.
A pragmatic, solution-oriented mindset.
Ability to balance technical quality with business priorities.
Autonomy, accountability and effective teamwork.
Openness to feedback and continuous learning.
Genuine interest in cybersecurity, privacy, ethical technology and open-source software.

Working environment

Luxembourg-based opportunity with a hybrid working arrangement.
International and collaborative engineering environment.
Professional development opportunities, including training.
Paid annual leave and a focus on sustainable work-life balance.
A culture emphasizing transparency, autonomy, privacy and shared success.

Interested?

If you enjoy building reliable backend systems and want to contribute to software where security and engineering quality are central, we would be happy to discuss the opportunity with you.

Apply through Skillhubs to learn more about the role and its technical environment.

Backend Software Engineer - PHP / API