Solutions Developer

About MixvoipWe are Mixvoip, a Luxembourg-based company providing Cloud Telephony, Connectivity, Cybersecurity, and Managed IT Services to businesses and public organizations. We design, operate, and support many of our solutions ourselves. When we see an inefficient process, a missing integration, or an opportunity to create a better customer experience, we like to build something that solves it. That’s where you come in. About the roleYou will join Mixvoip’s IT Services team as a Solutions Developer. Your role sits between software development, infrastructure, automation, and product design. You will build internal tools that make our teams more efficient, automate repetitive processes, connect systems through APIs, and contribute to customer-facing products. Projects can be very different from one another. You might build a small automation in Python, a backend service in Rust or C#, a React interface, an integration between several platforms, or a complete solution combining software, infrastructure, authentication, APIs, and physical devices. We are therefore not looking for someone attached to one specific framework. We are looking for someone who can understand a problem, choose an appropriate technical approach, prototype quickly, and turn the result into something secure, reliable, understandable, and maintainable. AI-assisted development is part of how we work. You should be comfortable using coding assistants and development agents such as Codex, Claude, or similar tools to explore codebases, build features, refactor, test, document, and accelerate development. The important part is not how much code AI can generate for you. It is whether you understand what is being built and remain responsible for the architecture, security, quality, and operation of the final solution. Key responsibilitiesDesign and develop internal applications, automation, and operational tools Contribute to customer-facing products and new commercial solutions Translate operational or business needs into practical software solutions Prototype ideas quickly and turn successful prototypes into production-ready systems Work across technologies such as Rust, Python, C#, TypeScript, React, Next.js, Vite, and similar tools Build and integrate APIs, webhooks, databases, internal systems, and third-party services Design frontend, backend, and service components when required Apply appropriate software architecture and design patterns without unnecessary complexity Implement authentication, authorization, and secure handling of application data Write maintainable, testable, and understandable code Review both human-written and AI-generated code critically Build automated tests and contribute to CI/CD and deployment processes Deploy and operate applications in Linux, Windows, containerized, cloud, or on-premises environments Troubleshoot across application and infrastructure layers, including logs, networking, databases, APIs, permissions, and services Implement appropriate logging, monitoring, and health checks Document architecture, dependencies, APIs, deployment procedures, and important technical decisions Identify manual or repetitive work that could be simplified through software or automation Work closely with systems engineers, network engineers, support teams, and other colleagues across Mixvoip What do we need from you?Strong software development fundamentals Professional experience building applications, tools, automation, platforms, or software products Experience with more than one programming language or technology stack Strong knowledge of at least one backend language such as Rust, Python, C#, or similar Experience with modern web development using TypeScript, React, Next.js, Vite, or comparable technologies Good understanding of APIs, HTTP, authentication, webhooks, databases, and system integrations Good understanding of software architecture and common design patterns Experience with Git, code reviews, testing, and collaborative development workflows Good understanding of application security Good infrastructure fundamentals, including networking, DNS, HTTP/HTTPS, TLS, operating systems, permissions, and reverse proxies Comfortable working with Linux and the command line Familiarity with containers and modern deployment practices Strong experience using AI coding assistants and development agents in real development work Ability to review AI-generated solutions critically and recognize when they are incorrect, insecure, or unnecessarily complex Ability to learn unfamiliar technologies quickly Good documentation habits Professional proficiency in English You do not need to be an expert in every technology we use. Strong fundamentals, adaptability, and good engineering judgment matter more to us than knowing a specific framework by heart. What would make you stand out?Experience with Rust, Python, C#, or .NET Advanced TypeScript and React experience Experience building internal tools or operational platforms Experience turning manual business processes into software and automation Experience developing customer-facing software products Experience integrating hardware, meeting room equipment, embedded devices, or IoT systems Experience with PostgreSQL, SQL Server, Redis, message queues, or event-driven architectures Experience with Docker, Kubernetes, CI/CD, or infrastructure-as-code Experience operating applications in both cloud and on-premises environments Knowledge of OAuth2, OpenID Connect, SAML, LDAP, Active Directory, or Entra ID Experience integrating Microsoft 365, Teams, Exchange, calendars, or meeting room technologies Good understanding of enterprise IT infrastructure and networking Experience with monitoring, observability, secrets management, and secure software development Contributions to open-source projects or personal technical projects French, German, and/or Luxembourgish Why Mixvoip?At Mixvoip, you will work on software that solves real problems. An internal tool might remove hours of repetitive work every week. An integration might eliminate an entire manual process. A prototype might become a product offered to our customers. You will work close to the people who use what you build, and across telecom, cloud, networking, cybersecurity, managed IT, software, and sometimes hardware. This also means you can work on a solution end to end: from the initial idea and architecture to the code, infrastructure, deployment, and operation. We encourage experimentation and rapid prototyping, while expecting production systems to be secure, reliable, and maintainable. You will have freedom in how you solve problems, together with responsibility for the technical decisions you make. A new way to apply: Join Mixvoip’s success storyWe would like to see more than your CV. Record a brief video with your smartphone and tell us about something you have built. It can be a commercial product, an internal tool, an automation, a personal project, or something completely different. Tell us what problem you were trying to solve, how you approached it, and what technical decisions you made. Please remember to attach your CV in PDF format too. Instead of a conventional motivational letter, we would also like you to use an AI tool of your choice. For this role, show us how you use an AI coding assistant or development agent to solve a technical problem. We are interested in how you guide the tool, what you verify yourself, and how you apply your own engineering judgment. PS: Want to know who you’ll be working with? Meet me, Antoine CAVELIERI’ve been with Mixvoip for 8 years, and my role is to help businesses make better use of their IT. With the IT Consulting team, we support customers who often have very different realities. Some have an internal IT department and need a reliable technical partner. Others rely on us for almost everything related to their infrastructure, users, security, cloud services, networks, and day-to-day IT operations. That variety is what makes this job interesting. One day, you may be working on Microsoft 365. Another day, you may be helping with virtualization, servers, storage, backups, Wi-Fi, Linux systems, scripts, migrations, or a customer project that does not fit neatly into one category. I like people who are curious, structured, and honest about what they know and what they still need to learn. In consulting, nobody knows everything. What matters is the ability to understand the problem, ask the right questions, investigate properly, communicate clearly, and take ownership until things move forward. I care a lot about practical solutions. Our customers are SMEs. They need systems that work, advice they can understand, and partners they can trust. Good consulting is not only about technical knowledge. It is also about listening, explaining, documenting, prioritizing, and staying calm when something goes wrong. I also believe that modern IT work should make good use of the right tools, including AI. Not to replace thinking, but to speed up research, scripting, documentation, troubleshooting, and daily operations. If you enjoy broad technical challenges, customer contact, autonomy, terminal work, small automation tasks, and the idea of helping many different businesses improve their IT step by step, then you could be a great fit for the team.