Head of HR (m/f/d) – full-time

LOCATION: Hamburg (hybrid remote work possible)
START: Immediately, Hiring on a rolling basis (Start: e.g. Jan/Februar 2026)

About Blockbrain

Your opportunity to enable critical growth in one of Germany’s leading AI startups by building scalable HR structures – from 40 to 200+ employees.

About Blockbrain

For medium-sized companies, knowledge is the last real competitive lever. But information is stuck in tools, databases, and SharePoint folders – or disappears with experts who retire. Knowledge work processes remain manual, even though AI could deliver direct ROI here. And while IT is still planning, employees have long been using ChatGPT, Perplexity, DeepSeek & Co – without control, without guidance, and sensitive data is flowing away.

Our mission: We elevate human knowledge with responsible AI.

With the Knowledge Bots platform, we create what companies really need: AI-supported knowledge management that can be implemented quickly, grows flexibly with the company, and functions compliantly across all processes, departments, and industries. Teams use our GenAI construction kit to build customized AI assistants, agents, and workflows in minutes—just like Lego.

Instead of standard solutions such as Copilot, which everyone uses and which offer no competitive advantage, companies are using their own knowledge and specific processes as a differentiator – enriched with internal and external data, without hundreds of vendor integrations. Everything on a central platform: no-code, enterprise-ready, seamlessly integrated into existing systems, and scalable via API.

What sets us apart:

Strong growth momentum : Strong VC funding, we win enterprise deals against MS Copilot, Perplexity, ChatGPT, Harvey & Co. – with the highest conversion and engagement rates in the industry

Category champions trust us: Roland Berger, EY, IONOS (consulting), Bardehle Pagenberg, SGP (legal), Bosch Rexroth, Motherson, Kärcher, Harting (industrial), Giesecke+Devrient, CHG Meridian, LBBW (finance), and many more

Experienced team with high talent density: Co-founder of Statista, Bosch Executive, WHU, Antler, IBM, Amazon, Trumpf – experts in big data, process automation, B2B SaaS, generative AI, and cybersecurity.

You will take responsibility for HR and professionalize our people strategy. Working closely with founders, C-level executives, and management, you will establish HR processes and structures that can keep pace with our rapid growth—without losing our startup spirit.

Why this role is crucial:

As a fast-growing AI startup, we are facing an exciting challenge: scaling from currently around 40 employees to 200+ in the next few years. To do this, we need someone who is responsible for HR structures that can keep pace with this growth – professional, scalable, without losing the startup spirit.

• Establishing and managing scalable recruiting processes for all departments
• Developing standardized scorecards and assessment frameworks to ensure cultural fit and professional quality
• Working closely with hiring managers to define clear role requirements
• Hands-on recruiting: conducting interviews, sourcing candidates, managing headhunters
• Building employer branding and diversifying recruiting channels to attract more qualified applicants
• Management of the ATS (Personio/Deel) and continuous process improvement

People & HR Operations

• Ownership for onboarding and offboarding processes
• Further development and scaling of existing People Ops processes
• Employee support: from contracts to personal concerns
• Performance management: establishing a feedback culture, structuring development discussions
• Ensuring compliance with German labor law
• Further development and anchoring of company values and cultural principles
• Development of measures to strengthen team cohesion and corporate culture
• Development of competitive compensation and benefits structures
• Management and optimization of the HR tech stack (Personio, Deel, Vanta, LinkedIn)

Qualifications:

Minimum 4-8 years of experience in HR, ideally in startup/scale-up environments (Series A/B). Alternatively, you have equivalent qualifications with relevant professional experience in setting up HR structures.

Your profile

Technical

• Startup/scale-up experience: You have already established or significantly developed HR in fast-growing companies (ideally seed/series A/B).
• End-to-end recruiting: Experience in establishing and managing recruiting processes, ideally in the tech environment.
• People operations: Solid knowledge of onboarding/offboarding, performance management, and employee relations.
• German labor law: Basic understanding to act in compliance and avoid typical pitfalls.
• HR tech stack: Experience with HRIS systems (ideally Personio), Deel, or comparable tools.
• Process thinking: You build scalable structures without becoming bureaucratic.

Personal

• Hands-on & pragmatic: You roll up your sleeves and don’t shy away from operational tasks.
• Startup DNA: You feel at home in fast-paced, dynamic environments and make decisions pragmatically.
• Empathetic & people-oriented: You understand people’s needs and create an environment in which they can grow.
• Structured thinking: Break down complex problems into solvable steps.
• Strong communication skills: Fluent in German & English, proactive, clear.
• Culture champion: You exemplify values and strengthen a culture that attracts and retains top talent.

What we offer

• Full-time position in Hamburg: 3-4 days/week on site at the central office, flexible working hours.
• Ownership & real impact: Direct collaboration with founders and management – direct influence on growth, talent density, and culture.
• Creative freedom: You build HR according to your vision and take People & Culture to the next level.
• Growth opportunity: We are growing rapidly – you can grow with us and your role
• Attractive compensation: Competitive salary plus additional benefits
• Young, international team with high talent density and regular off-sites
• Flexible HR tech stack: Personio, Deel, Vanta, LinkedIn – expandable as needed

How to apply

Blockbrain is an equal opportunity employer. We celebrate diversity and are committed to creating an inclusive work environment.

If you’re interested in professionalizing HR at a leading AI startup, truly helping people, and creating processes that work and scale, you’ve come to the right place.