Senior Fullstack Engineer - Custom Solutions

We’re looking for an experienced Senior Fullstack Engineer to join a newly formed team at Staffbase that builds custom solutions — extending the functionality and capabilities of our award-winning employee communications platform to meet real customer needs. You’ll own solutions from beginning to end: shaping use cases together with stakeholders, building them across the stack, and validating them with the people who use them. You’ll also help bring structure to a growing team of mid-level engineers and mentor them along the way. We’re looking for empathetic, motivated team players who are driven by ownership and growth. Let’s talk!

As part of our tech stack, we use: React.js, TypeScript, JavaScript, Node.js, Kotlin, Go, Java, MongoDB, REST APIs & SDKs, Docker, Terraform, Selenium and Cypress, to name a few.

Our environment

• Working with skilled and like-minded professionals in a team that values diversity and inclusivity
• We aim to create a flexible and agile work environment that promotes the well-being and work-life balance of our employees
• We believe that team events during working hours play a vital role in building an exceptionally effective team, and we encourage them
• We are enthusiastic about technology and committed to using it to improve the world
• We follow the “You build it, you run it” approach and take pride in it

The team

You’ll join a newly formed team dedicated to building custom solutions that extend the Staffbase platform for our enterprise customers. We turn specific customer needs into reliable, scalable extensions — widgets, plugins, and integrations — that make our product work exactly the way each customer needs it to.

Because the team is new, there’s real room to shape how we work: to set engineering standards, bring structure to our processes, and grow together. That’s where you come in.

What you’ll be doing

• Own the development of custom solutions end-to-end — from technical design through implementation, testing, and release
• Partner with stakeholders (customers, consultants, and internal teams) to define and detail use cases before development, then validate solutions and gather feedback afterward
• Build across the stack: customer-facing UI in React and TypeScript, backend services, and integrations with Staffbase and third-party APIs
• Mentor mid-level engineers and help bring structure, engineering standards, and good practices to a newly formed team
• Work in a cross-functional, agile setup and produce high-quality, well-tested code
• Give and receive valuable feedback in our code review process, and continuously learn and share knowledge with your peers
• Work iteratively — pushing code frequently, keeping a healthy CI/CD pipeline, and automating where it helps

What you need to be successful

• Solid professional experience (typically 5+ years) as a fullstack developer, including working within engineering teams and owning solutions from concept to delivery
• Strong frontend skills with React.js, TypeScript, and JavaScript, paired with solid backend experience (e.g. Kotlin, Java, or Node.js)
• Confidence working with REST APIs and SDKs, and integrating with external systems
• Experience mentoring or guiding less-experienced developers, and a knack for bringing structure to how a team works
• Comfort working directly with stakeholders — you can translate business needs into technical solutions and validate them afterward
• A strong focus on quality, clean code, testing, and continuous learning
• Fluent written and spoken English and German — both are required, as you’ll work closely with German-speaking stakeholders and customers in the region
• A self-starter who works well both independently and as part of a team
• You understand and appreciate diversity and inclusivity in the workplace

Nice to have

• Experience with Go, MongoDB, Docker, Kubernetes, GitHub Actions, Terraform, Prometheus or Grafana
• A background in professional services, consulting, or building custom, customer-facing solutions
• Enterprise integration concepts such as SSO, SAML, OIDC, or SCIM
• A good understanding of REST and microservices architecture

What you'll get

• Competitive Compensation - we offer attractive salary packages including LTIP (unit-based Long Term Incentive Plan)
• Flexibility - we offer flexible working time models and the option of hybrid work, and support this with a yearly flex work allowance of €1560
• Recharge - with 31 vacation days annually (incl. one floating holiday), plus pro rata fully paid Fridays off during August
• Support - we offer offering a company pension scheme
• Volunteers Day - you’ll get one day off per year for supporting a social project