Software Engineer - EO L5 in London

Personio's intelligent HR platform helps small and medium-sized organisations unlock the power of people by making complicated, time-consuming tasks simple and efficient. Our team of 1,500 Personios is building user-friendly products that delight our 15,000+ customers and their million employees.

We’re hiring a Senior Software Engineer to join our EO team at Personio. This is a role that sits in a senior, high-trust engineering team working on core platform capabilities that power large parts of the Personio product. EO sits at the intersection of platform and customer-facing product. The systems built here are used by many other teams across Personio and directly impact how admins manage company structures, permissions, and employment-related data.

This role is primarily back-end focused, with a strong preference for engineers who are comfortable contributing to front-end work when needed (React). You don’t need to be a classic full-stack engineer, but you should be happy operating across the stack where it makes sense.

What You’ll Be Working On

Over the next 6–12 months, the team will spend most of its time on new customer-facing feature development, with the remaining time focused on modernising and improving existing foundations.

You’ll contribute to a set of initiatives centred on:

• Evolving core platform capabilities that power how organisations are represented and managed in Personio (data models, APIs, and workflows)
• Building secure, scalable backend services that support complex permissioning, delegation, and governance needs
• Improving foundations and system quality (performance, observability, robustness, tech-debt reduction, and operational excellence)
• Designing for change at scale, including backward-compatible migrations, versioning strategies, and safe rollout patterns
• Cross-team collaboration with multiple product and platform teams to ensure changes integrate cleanly and scale safely across the ecosystem

What You’ll Do

• Design, build, and evolve scalable backend systems that are used across Personio
• Work in ambiguous problem spaces, proactively identifying missing information and dependencies
• Balance product thinking with technical excellence, shaping solutions rather than just executing tickets
• Collaborate closely with Product and Design, while also managing a wide range of technical stakeholders
• Contribute to a senior-heavy team through code reviews, design discussions, and technical leadership
• Occasionally contribute to front-end work where it unblocks delivery or improves outcomes

What We’re Looking For

• Strong experience as a backend engineer working on production systems
• Comfort operating in ambiguous environments with changing priorities
• A product-minded approach to engineering and problem solving
• Ability to communicate clearly with engineers, product managers, and teams across the organisation
• Experience with Java, Kotlin, or similar languages is helpful, but not essential
• Front-end experience (React) is a strong plus, but not a hard requirement

Why Personio

Personio is an equal opportunities employer, committed to building an inclusive culture where everyone feels supported. We value in-person collaboration while offering flexibility. This role requires 2 days per week in your contracted office location, with the remaining days flexible. You’ll also get 20 Flex Days per year to work remotely from other locations.

Our benefits include:

• Competitive salary, benefits, and pre-IPO equity
• 28 days paid holiday, plus additional days after 2 and 4 years
• One fully paid Impact Day per year
• Generous family leave, mental health support, and sabbatical options
• Regular team events, office snacks, drinks, and weekly catered lunches