LLM Engineer

Join SLAY – Build the Future of Digital Life

SLAY, founded in December 2022, is one of the fastest-growing mobile startups in the world. With 5 apps and games reaching #1 in the App Store across 3 continents, we’re backed by world-class investors including Accel, Kevin Weil, Riccardo Zacconi, Scott Belsky, and Ilkka Paananen.

Our mission: To create digital life through AI and become the leading company for virtual friends that live, grow, and evolve like humans. Pengu, our flagship character app, is already the #1 AI character IP in the US and Europe.

Your Role: LLM Engineer

We are looking for an LLM Engineer to join our high-performance team in-person at our Berlin office. You’ll play a key role in designing data pipelines, fine-tuning architecture, and evaluation systems. You’ll move fast, own decisions, and close the loop from experimentation to production.

What You’ll Do

• Design and implement LLM fine-tuning pipelines and evaluation loops
• Integrate LLMs into production systems and products
• Make smart tradeoffs between technical ambition and feasibility
• Translate the latest AI research into real-world applications
• Work on data collection, model training, inference, and deployment

Who You Are

• Relentlessly driven, with a passion for winning and building world-class AI products
• Experience with full-stack model deployment and ML infrastructure
• Strong software engineering skills in production environments
• Clear product thinking and the ability to move fast under pressure
• Bachelor’s degree in Computer Science or equivalent practical experience
• You thrive in an in-person, high-intensity team based in Berlin

How We Work

• Berlin-Only: No remote/hybrid — full in-office setup
• A-Players Only: We hire top talent and pay above-market salaries
• Grind: We work and communicate on nights and weekends. We move fast.
• High Urgency: Turn weeks into days. Hours into minutes.
• Fast Firing: We move on quickly if there’s not a fit. Paid trials are standard.
• Flat Structure: Titles reflect responsibility, not hierarchy
• Mission-Driven: You’re excited about building the future of virtual characters

Benefits & Compensation

• Total Compensation: €200k – €500k (includes salary + stock options)
• Office Perks: Apple Studio Displays, Herman Miller chairs, and premium workspace in Berlin Mitte
• Full Commute Reimbursement: We cover 100% of your travel costs
• Gym Membership: We pay for your fitness
• Visa Sponsorship: We assist with all relocation and visa paperwork
• Bureaucratic Support: Help with German taxes, healthcare, social security, and admin

Ready to Build Something Extraordinary?

If you’re an A-player ready to grind, build, and scale something legendary, this is your chance. Let’s talk.