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Principal LLM Engineer

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Supercell

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Location:
Finland, Helsinki

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Category:
IT - Software Development

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Contract Type:
Not provided

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Salary:

Not provided

Job Description:

Supercell is looking for an entrepreneur disguised as an engineer — someone who’s obsessed with building real things, thrives on autonomy, and is energized by big, undefined problems. We want a person who treats AI as a playground for creation — who can imagine bold applications, prototype fast, and ship production-grade systems that change how we work and play. Someone who wants to set the standard for what “great” looks like in LLM engineering — and who’s excited by the idea of doing it inside one of the most creatively free companies in the world.

Job Responsibility:

  • Build and ship bold ideas: Design, prototype, and deliver production-grade LLM and agentic systems — from creative tools to intelligent in-game and internal agents
  • Own the craft: Define how we design, evaluate, and scale LLM applications across Supercell. Set the bar for quality, reliability, and creativity
  • Move fast and take risks: Try new frameworks, break things safely, and push the limits of what’s possible with emerging models and tools
  • Collaborate like a founder: Work closely with game teams, engineers, and artists to find high-impact opportunities — and make them real
  • Inspire and enable: Help others across Supercell build confidently with AI, sharing insights, frameworks, and reusable components

Requirements:

  • Proven track record building production LLM or agentic applications — ideally shipped or widely used
  • Deep technical grounding in Python, APIs, orchestration, evaluation, monitoring, and modern LLM frameworks (LangChain, LlamaIndex, OpenAI, Anthropic, vLLM, etc.)
  • Entrepreneurial mindset: You’ve built from scratch, taken bets, and thrived in environments with freedom and ambiguity
  • Strong product sense and creativity — able to turn vague ideas into concrete, delightful experiences
  • Excellent communicator and evangelist — you bring others along and create excitement
  • Curiosity and appetite for risk and experimentation. You move fast and learn faster

Nice to have:

Bonus: interest in games, creativity, or building tools that empower others

What we offer:

Relocation support: dedicated mobility team and partners will support you throughout your move

Additional Information:

Job Posted:
December 12, 2025

Employment Type:
Fulltime
Work Type:
On-site work
Job Link Share:

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