Senior Full Stack Developer - PHP&WordPress (m/f/d)

Permanent employee, Full-time · Karlsruhe, Barcelona

Your mission

Many businesses struggle with web development complexities, balancing legacy systems and new technology. As a Senior Full-Stack Developer - PHP&WordPress with us, you'll help clients by building web solutions that deliver results.
We work with diverse clients on strategic maintenance and new applications using cutting-edge technology. This offers unique opportunities for growth and varied challenges.
We're seeking a skilled Senior Full-Stack Developer - PHP&WordPress to join our team. You'll handle architecture, development, and maintenance of high-performance e-commerce and content platforms. This role requires strong PHP and WordPress expertise, plus a commitment to modern development practices, code quality, and security.

You are doing this with us:

Architect, develop, and maintain complex WordPress and WooCommerce applications.
Write secure, efficient, and maintainable code in PHP and JavaScript.
Optimise application performance through advanced caching strategies (Varnish, Nginx Cache) and database tuning
Perform in-depth debugging and performance profiling using tools such as Xdebug or XHProf to diagnose and resolve complex issues.
Lead and participate in code reviews and contribute to architectural design discussions.
Engineer solutions for complex requirements, including multilingual and multicurrency e-commerce systems.
Manage contributions across multiple client projects, maintaining clear documentation and diligent time tracking for billing purposes.
Proactively identify challenges, propose effective solutions, and communicate clearly with team members and stakeholders to drive projects forward.

Your experience

You have valuable experience with:

Programming PHP and JavaScript, TypeScript, JSX/TSX, HTML5, CSS, Sass, Twig
Minimum of five years of professional experience in full-stack development.
Expert proficiency in PHP, with a deep understanding of Object-Oriented Programming (OOP), SOLID principles, and procedural code structures.
Extensive experience with custom WordPress and WooCommerce development.
Strong proficiency in database design and management with MySQL, including advanced SQL query optimisation.
Thorough understanding of web security principles and experience implementing secure coding practices.
Demonstrated experience with a modern templating engine, such as Twig.
Hands-on experience with automated testing frameworks and CI/CD processes.
In-depth knowledge of HTTP protocols, headers, and reverse proxy caching systems.

Nice to have:

Experience developing RESTful APIs or GraphQL services.
Familiarity with modern front-end frameworks (e.g., React, Next.js) and TypeScript.
Experience with PostgreSQL.
Knowledge of search platforms such as Elasticsearch or OpenSearch.
Experience working with AI tools or integrations in a development context.
Implement and manage automated testing (e.g., Playwright, Cypress) and CI/CD deployment pipelines.
Contributions to open-source projects.
Experience with modern cloud and deployment platforms (e.g., Northflank, Vercel, Cloudflare).
Familiarity with web accessibility standards (WCAG)

Our Tools

Our development workflow utilises the following tools and technologies:

Version Control & CI/CD: Git, GitHub, GitHub Actions
Development Tools: Docker, Composer, npm, WP-CLI, SSH
Project Management & Collaboration: Asana, Notion, Slack, Google Workspace

The results

This comes out of your work in the end:

Solid responsive layouts and interactions
Functionality that is well-tested and resolves the needs of the customer
An implementation approach that can be maintained and updated easily
Code that is clean and can be understood and extended by others
Time estimates that are reliable

Your peers

You'll be working with these folks:

Project Manager
UX- & UI designer
Digital Business Consultants
Marketeers

Our promise

What we live by and what we love about our work:

Taking ownership and working independently is part of who we are. Flexible hours and working from home go without saying. We see our work as an important part of life, but just one part, and one that should adapt to everything else that matters.
You'll find a set of values here that we not only believe in but truly live every day.
We’re a diverse, international team of digital enthusiasts who are passionate about their topics — just like you.
You’ll get regular feedback from mentors. And because we’re always evolving and aim to improve a little every day, we value it the other way around too. Share your ideas, speak up when something’s off, and tell us how we can do better..
We’ve got fresh fruit, coffee, and soft drinks in all our offices. And we regularly get together for lunch.
Togetherness matters to us: we meet for team activities and workshops in Karlsruhe, Cologne and Barcelona, or virtually, of course.
If you’re keen to grow, we’re here to support you: with language courses, conferences and other training opportunities. But as always: those who take the initiative get the most out of it. So talk to us about what you'd like to pursue.
We’re pet-friendly: after a quick intro, dogs are welcome in the office.
We make sure you have what you need to do great work: phone plan, the right hardware, BahnCard or JobRad — whatever gets you going.

In a nutshell: You’ll help shape digital formats with our clients, set up smart processes and infrastructures, share both creative and technical know-how, and most importantly get things done. You’re the one who makes it happen. We don’t believe in “can’t”, but we do believe it’s up to you to drive what should.

Start date: Immediately
Model: Hybrid (2 days/week working at the office)
Location: Barcelona or Karlsruhe
Salary range: 48,000 – 65,000 EUR/anno
Required experience: Minimum 8 years experience in the field

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About us

We create digital impact for our clients. Since we believe that a solid business strategy can only thrive when all aspects of the digital world are considered, we need hands-on experts for all digital disciplines to achieve this. Our services entail digital analytics, strategic planning, project management, UX/design, development, marketing and the education of our client’s employees.

We have offices in Karlsruhe, Cologne and Barcelona and alongside netzstrategen more companies belong to our family to complete our clients’ digital workbench and of our own products and businesses.

Our clients are from many different industries and sizes; we are working for big health corporations as well as small local retailers. We are independent from our clients and other institutions - so we don’t have to answer to nobody but to ourselves. This allows us to work with an open and honest attitude when it comes to suggestions for strategies and implementations. Our clients appreciate this a lot.

Honesty and sincerity are enormously important to us und we live our values in our daily work. We all like coming to our offices, to see our clients and our colleagues. Our community is important to us and we invest time and energy in nurturing it. Work to us is more than just bashing stones for a dime :-)

We try to make decisions together in the company; in our weekly lunch meetings, in our frequent plannings or in our bi-annual cross company workshop, where we all come together physically or virtually to spend some time together and try to keep the companies on the right path.

Sounds like your thing? Then we look forward to hearing from you!

Apply for this job

We are looking forward to hearing from you!

Thank you for your interest in our company and team. Please fill out the following short form. Should you have difficulties with the upload of your data, please send an email to jobs@netzstrategen.com.