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Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # MID-Level/Senior Software Engineer - **Company:** Pegamento - **Location:** Zeist, Netherlands - **Experience:** Experienced - **Contract:** Permanent contract - **Skills:** JavaScript (Programming Language), PHP (Programming Language), Application Programming Interfaces (APIs), Artificial Intelligence, Artificial Neural Networks, Software Quality, Databases, Continuous Integration, Data Centers, Relational Databases, Cursor, DevOps, Human-Computer Interaction, Session Initiation Protocols, Python (Programming Language), Search Technologies, Software Engineering, TypeScript, WebRTC, ReactJS, Retrieval-Augmented Generation, Large Language Models, Claude Code, Technical Debt, Backend, Kubernetes, Hardware Infrastructure - **Published:** October 26, 2026 - **Apply:** https://www.nationalevacaturebank.nl/vacature/fd0075f6-879a-4048-8d06-6a78e9cc8782/mid-level-senior-software-engineer ## About the Role We distinguish between what is necessary to succeed in this role and the knowledge you can develop while working with us. The exact number of years of experience is less important than demonstrated independence, professional judgment, and a track record of results in a production environment. + Several years of experience as a software engineer in an environment where real users depend on your code. + You have proven proficiency in either Python or JavaScript/TypeScript with React and want to develop the ability to independently build a complete feature-from database to user interface-within a year. + You work with relational databases and APIs on a daily basis and understand schema design, migrations, and scalability. + You design before you build, weigh alternatives and technical debt, and write maintainable, testable software. + You use AI development tools critically: you use them to speed up the process, but you also verify assumptions, security, and quality. + You collaborate constructively with engineers, designers, consultants, and project managers. You listen to the client, identify risks and dependencies early on, and can professionally say "no" without damaging the relationship. + You communicate fluently in Dutch or English, both verbally and in writing. A nice bonus Experience with one or more of the following topics makes us especially curious: SIP, WebRTC, or media streams; LLMs, RAG, vector search, or on-device AI; mobile performance; customer contact, CX, telephony, or CRM; the public sector or healthcare; containers, Kubernetes, CI/CD, and observability; or PHP for existing components. No experience with AI or SIP? You can learn those if you have a solid technical foundation. ## Description Wanted: Mid-Level/Senior Software Engineer with strong skills in Python or React. Why work with us: - We improve your accessibility - We enhance your customer experience - We increase your efficiency Want to know how we've been using AI to enhance the customer experience for years? Consult with an expert "With Pegamento, we found not just a supplier, but a true partner in change. Thanks to their expertise and our joint DevOps approach, we have made great strides in a short time. The technology supports our people so they can focus on where they make a difference: personal contact with entrepreneurs. " Laila de Rooij Director of Valuable Customer Contact Chamber of Commerce You'll learn the rest from us. You'll build software that actually helps people stay on track. ROLE Full-stack - or on the way there SCOPE 32-40 hours LOCATION Zeist / hybrid About Pegamento and this role Pegamento develops and manages digital workplaces and customer engagement solutions for organizations where accessibility is not just a side issue. Our applications, portals, and platforms support healthcare institutions, municipalities, educational organizations, industry, and helplines, among others. If our software goes down, people won't be able to properly reach their municipality, primary care physician, or care provider. You will therefore be working in complex client environments with high standards for privacy, security, performance, and continuity. We build on our own infrastructure and make decisions that must remain viable for years to come. To that end, we're looking for an engineer with experience in production software, the ability to exercise professional judgment, and a willingness to take responsibility for the results. The Core of the Role You'll take independent ownership of a portion of our system landscape. You'll think before you build, provide clear justification for technical decisions, and ensure that quality isn't left to chance. In addition to code, you'll also deliver clarity, rationale, and a solution that colleagues can understand, manage, and further develop. What you'll help build You'll work with Python and React. You'll start on the side where you're strongest and grow toward the other. You'll join a team that: + trains its own neural networks on our on-premises GPU infrastructure; + deploys private LLMs and open-weight models, both in the data center and on-device; + integrates SIP and other real-time communication protocols; + builds multisite platforms that support thousands of users. We use AI tools such as Cursor and Claude Code on a daily basis. You use these tools critically and efficiently; as an engineer, you remain responsible for design, code quality, security, and the production outcome. What We Expect in the First Year In your first 90 days + You'll deliver fully functional features within an existing codebase and, in coordination with the design and backend teams, deploy them to production. + You'll participate fully in reviews, refinement sessions, and architecture sessions, and provide well-reasoned feedback on others' work as well as your own. + You'll familiarize yourself with a specific domain and identify early on where improvements can be made-whether in terms of technology, collaboration, or our work processes. Within 12 months + You take ownership of a component, service, or domain and can explain architectural decisions to colleagues and clients. + You contribute to reusable components, patterns, CI/CD, and security-by-design, and help reduce the use of ad-hoc solutions. + You mentor less experienced colleagues and translate possibilities in AI, LLMs, SIP, and real-time events into practical solutions. What You Bring to the Table, Send us your resume or profile, a brief cover letter, and-preferably-an example of work you're proud of-such as a repo, case study, video, or code snippet-along with a few lines explaining the choices you made. Not sure if your profile is a perfect fit? Apply anyway and let us know what your concerns are. Recruitment in Response to This Job Opening We receive a great deal of interest in our job openings and are able to effectively reach candidates through our own channels. For this reason, we do not use external recruitment or staffing agencies to fill our positions. Unsolicited outreach regarding our job openings is therefore not appreciated. We kindly ask agencies not to contact us regarding this matter. A customer service representative reviews a cost report at a modern desk equipped with a laptop, headset, and coffee in a warm office with natural light.