HR Generalist

Reflection is a research lab making intelligence open and accessible for everyone to use, customize, and build on. We build open models that let anyone control their intelligence and help shape the future of AI. Our mission: make intelligence open and accessible to all.

We're looking for an HR Generalist to be a hands-on, go-to people partner across the business. This role sits at the intersection of People Operations, HR Generalist, and HR Business Partnering — covering the full employee lifecycle while also helping to shape the people practices and frameworks that will support the company as it grows.

You'll work closely with managers and employees alike: rolling up your sleeves on day-to-day HR operations, supporting recruitment and onboarding, managing employee relations, and partnering with leaders on performance and organizational effectiveness. This is a broad, varied role that suits someone who's equally comfortable building a process as they are navigating a complex ER case or coaching a manager through a difficult conversation.

What You'll Do

• Serve as the primary People Team point of contact for employees and managers in the UK.

• Partner with managers on employee relations matters, performance concerns, manager coaching, team effectiveness, and organizational changes.

• Manage employee relations cases end-to-end, including disciplinaries, grievances, performance improvement plans, and investigations, in line with UK employment law.

• Support organizational planning activities including team structures, role clarity, workforce changes, and manager effectiveness.

• Implement global People programs and processes locally, ensuring they are delivered effectively and compliantly within the UK.

• Coordinate local execution of performance reviews, talent discussions, compensation processes, and other cyclical People programs.

• Own UK People Operations administration across the employee lifecycle, including onboarding, employment changes, leave administration, and offboarding.

• Manage UK-specific benefits, pension administration, leave programs, and other local employee offerings.

• Partner with payroll, benefits providers, legal counsel, and external vendors to ensure accurate and compliant administration.

• Maintain employee records, documentation, policies, and HR systems with a high degree of accuracy.

• Identify opportunities to improve local processes, employee experience, and operational efficiency while aligning with global People practices.

• Ensure compliance with UK employment legislation and support implementation of new regulatory requirements as needed.

What We're Looking For

• 5+ years of experience in an HR Generalist, People Operations, HRBP, or similar role supporting UK employees.

• Strong working knowledge of UK employment law and employee relations practices.

• Proven experience independently managing employee relations cases from intake through resolution.

• Experience administering UK benefits, pensions, leave programs, and other employment-related processes.

• Experience implementing and executing People programs in partnership with a broader People team.

• Strong organizational skills and attention to detail.

• Excellent judgment, discretion, and ability to handle sensitive situations.

• Experience working with HRIS platforms and employee data management.

• Ability to operate effectively in a fast-paced, high-growth environment with evolving priorities.

Preferred Qualifications

• Experience supporting a technology or high-growth company.

• Experience working as part of a distributed or global People team.

• Experience supporting international employees or partnering across multiple jurisdictions.

• Familiarity with Rippling or similar HRIS platforms.

We believe that to make intelligence open and accessible to all, you need to start at the foundation. Joining Reflection means building from the ground up as part of a talent-dense team. You will help define our future as a company, and help define the future of open foundational models.

We want you to do the most impactful work of your career with the confidence that you and the people you care about most are supported.

• Top-tier compensation: Salary and equity structured to recognize and retain our talent globally.

• Stock options: Everyone who joins and contributes to Reflection's success gets to share in the upside through stock options.

• Health & wellness: Comprehensive medical, dental, vision, and life, with an annual wellness allowance.

• Meals: Lunch and dinner are provided in the office daily.

• Life & family: 22 weeks paid parental leave for all new birthing and non-birthing parents, including adoptive and surrogate journeys.

• Vacation days: Unlimited paid time off in the U.S. and 30 days in the U.K.

• Sponsorship support: We sponsor visas to help exceptional talent join our team and support long-term immigration pathways where applicable.

• Team building: We have regular off-sites, happy hours, and team celebrations.