Senior Backend Developer (Kotlin)

Personio's intelligent HR platform helps small and medium-sized organizations 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 1.5 million employees. Ready to make an impact from day one?
The Role
This role requires
2 days per week
in the office and is based in
Munich, Berlin or Dublin
.

As a Staff Software Engineer in our Recruiting team, you'll set the technical direction for one of Personio's biggest revenue drivers — the product customers use to run their entire hiring process — alongside Whistleblowing and Workforce Planning. You'll join a large, senior-heavy team that balances mature, high-traffic systems with new, AI-led capabilities like AI screening and smart candidate pipelines, and you'll take on the hardest, least-defined problems: the ones that often reach beyond the team's own boundaries.

What You'll Do

• Identify and disambiguate the hardest problems — including ambiguous ones that span beyond the team — and turn them into clear, solvable work for others to build on.
• Set technical direction across Recruiting, Whistleblowing and Workforce Planning, making architecture and design decisions that hold up across the platform.
• Drive initiatives that cross team lines, aligning with staff engineers and partner teams across the Apps area and the wider platform.
• Invest in the success of every project and engineer on the team — not only your own work — through design guidance, mentoring, and unblocking others.
• Shape the team's AI-led capabilities, such as AI screening and smart candidate pipelines, from approach through to delivery.
• Lead the modernisation of legacy systems while keeping a major revenue-driving product reliable for some of our most demanding customers.
• Collaborate cross-functionally with Product, Design, and partner teams, representing the domain credibly in cross-team and architectural discussions.

What You Need To Succeed

• Extensive software engineering experience designing and operating complex, distributed systems in production (full-stack; strong backend or frontend depth both welcome).
• High autonomy in ambiguity — you find and frame the right problems, especially the messy ones that cross team boundaries, before solving them.
• Strong ownership at scale — you feel accountable for the success of the whole team's output, not just the code you write.
• A growth mindset — you raise the bar for yourself and the engineers around you, and grow others in the process.
• Strong system design and architecture skills that extend well beyond a single team's scope.
• Product and business judgement — you connect technical decisions to customer and business outcomes.
• Influential communication — you align engineers and stakeholders across teams around a shared technical direction.

Why Personio
Personio is an equal opportunities employer, committed to building an integrative culture where everyone feels welcomed and supported. We embrace uniqueness and understand that our diverse, values-driven culture makes us stronger. We are proud to have an inclusive workplace environment that will foster your development no matter your gender, civil status, family status, sexual orientation, religion, age, disability, education level, or race.

At Personio, we value in-person collaboration while also offering flexibility. This role is office-based, with 2 required days in your contracted office location. The remaining days can be worked from home or in the office if you prefer. In addition, you’ll have 20 Flex Days per year to work remotely from other locations.

Aside from our people, culture, and mission, check out some of the other benefits that make Personio a great place to work:

• Receive a competitive reward package – reevaluated each year – that includes salary, benefits, and pre-IPO equity
• Enjoy 28 days of paid vacation, plus an additional day after 2 and 4 years
• Make an impact on the environment and society with 1 (fully paid) Impact Day
• Receive generous family leave, child support, mental health support (including 24 sessions per year with Oli for yourself and 10 sessions for a significant other), and sabbatical opportunities
• We enjoy gathering for meals, cultural initiatives, and events like local Summer Sessions and year-end celebrations. There's also healthy snacks, drinks, and a weekly catered lunch.

We're hiring on behalf of a Haystack partner!

The Role

• Plan and technically lead architectural decisions for the development and enhancement of applications
• Create architectural concepts, decision documentation, and technical guidelines
• Collaborate with team leads, product owners, and tech leads to design robust solutions
• Actively participate in software development (approx. 40%), including architecture PoCs, core modules, refactoring, and blueprints
• Coordinate with other Software and Solution Architects within the company
• Ensure code quality through code reviews and conduct architectural workshops to impart suitable architectural and design patterns.

What You'll Need

• At least 7 years of experience in software development, with several years primarily responsible for technical architectural decisions
• Excellent Python skills and experience in at least one other technology (e.g., TypeScript/React or C#/.NET)
• Experience developing productive applications with generative AI models (e.g., LLM-based assistance systems, conversational AI, RAG architectures, or AI Agents) and knowledge of relevant frameworks and libraries
• Solid practical experience in agile methodologies such as Scrum or Kanban
• Experience with cloud-native architectures on Microsoft Azure and with Azure DevOps for CI/CD, deployment, and operational processes
• Strong communication skills and very good English (min. C1 level) and German (min. B2 level) spoken and written language skills.

What's On Offer

• Flexible working hours to accommodate personal needs
• Attractive special payments, such as a company success bonus and other performance-based salary components
• Company health management, including E-Gym Wellpass and company pension scheme

Apply via Haystack today!

We’re looking for a talented
Senior
Software Engineer
with strong Kotlin skills (or Java and willing to learn Kotlin) to join us in Berlin or Munich.

In the Foundation Division of FlixTech, our Finance Technology Stream helps the business grow efficiently by delivering smart, compliant, and automated finance solutions. We keep things simple for our internal users so they can spend less time on manual tasks and more time on what matters. The team you will join is not focused on user-facing experiences or polished UIs. Our success is measured by data correctness, consistency, and trustworthiness, even in complex and evolving business scenarios. You’ll be part of a self-managed, cross-functional team with a Product Owner and fellow Software Engineers, directly supporting new country launches, new business models, and the continuous evolution of Flix’s financial backbone.

This role is well-suited for someone who enjoys ownership, working close to real business problems, and contributing to the long-term foundations of an international company. If you value collaboration, thoughtful engineering, and building systems that need to be right, not just fast, we’d love to meet you.

About The Role

• Design, develop, and maintain backend services using Kotlin
• Build and evolve scalable, event-driven systems that process, validate, and expose financial data
• Use AI tools such as Claude Code and Copilot conscientiously to assist in faster and higher-quality development
• Collaborate closely with the Product Owner and Finance stakeholders to translate business requirements into robust technical solutions
• Ensure data accuracy, traceability, and auditability across financial and accounting flows
• Improve system reliability, observability, and performance for business-critical processes
• Contribute to clean code, architectural discussions, and continuous improvement of engineering practices

About You

• 5-7 years of experience developing backend systems, with Java or preferably using Kotlin
• Hands-on experience building backend services using the Spring ecosystem (e.g. Spring Boot, Spring Data)
• Experience with event-driven design (e.g. asynchronous processing, messaging, domain events)
• Practical experience with cloud platforms (preferably AWS, or similar)
• Solid understanding of databases, both NoSQL (e.g. DynamoDB) and/or relational systems
• Comfortable working in complex, data-heavy domains (ideally Finance), where investigation, analysis, and precision are key
• Communicate clearly in English, open-minded, curious, and motivated to continuously improve both yourself and the systems you work on

We recognize that everyone carries a unique set of valuable skills and experiences. If you think you could have an impact even though you don't meet 100% of the requirements, we still encourage you to apply. We want to hear from you!

What We Offer

• Travel perks: 12 free Flix vouchers + 12 discount vouchers for friends & family.
• Work from (M)Anywhere: Depending on your role, work from another location for up to 60 days per year.
• Hybrid work model: We are an office-first company, but we offer flexibility to balance work and life.
• Wellbeing support: Access confidential 1:1 counselling, courses, and stress management for yourself and up to four family members.
• Learning & Development: Take advantage of language classes, training courses, and expert-led sessions to grow your skills.
• Mentoring Program: Connect with experienced colleagues to gain insights and accelerate your career.

To view more local benefits specific to each office location, please check out this link:
Locations - Flix Career
Why Join Flix?
At Flix, you’ll find teams that rally together to overcome challenges and spark creativity. We believe in ownership culture - giving you the freedom to take initiative, make an impact, and shape your own career path.

As we continue to expand across the globe, you can make a real difference in how we work.

If you’re ready to grow and lead your journey, Flix is the place for you!

Engineering Munich, Germany Full-time On-site

About Offgen
offgen is building the next generation of AI-powered productivity tools for consulting and finance teams, starting with PowerPoint. We're a small, ambitious team based in Munich, working with some of the world's leading firms. We move fast, set a high bar, and give everyone real ownership from day one.

About The Role
You lead the development of offgen's AI capabilities — designing robust integrations, building intelligent pipelines, and pushing the boundaries of what our product can do. This is a technical leadership role at the intersection of applied AI and production engineering.

Your responsibilities

• —AI Systems Engineering: Architect and implement LLM-powered features, retrieval pipelines, and AI workflows.
• —Model Integration: Evaluate, integrate, and fine-tune models and APIs to meet product requirements.
• —Infrastructure: Design scalable, reliable infrastructure for AI workloads in production.
• —Technical Leadership: Set engineering standards, mentor engineers, and drive technical decisions.
• —Research Translation: Bridge the gap between cutting-edge AI research and practical product features.

Your profile

• —5+ years of software engineering experience, with at least 2 years focused on AI/ML systems.
• —Deep expertise in Python and experience building production AI applications.
• —Solid understanding of LLMs, RAG architectures, embeddings, and prompt engineering.
• —Experience with cloud platforms (AWS, GCP, or Azure) and containerised deployments.
• —Strong engineering rigour — you care about correctness, observability, and maintainability.
• —Ability to work autonomously and drive complex projects from concept to production.

What we offer

• —A rare opportunity to shape the AI architecture of a product from the ground up.
• —Significant equity and competitive senior-level compensation.
• —Direct collaboration with the founders and full technical ownership.
• —A small team of strong engineers where your decisions matter.
• —Flexible working arrangements and a culture built on trust and quality.