Machine Learning Engineer (LLM)

Bjak; City Of London; Hybrid; GBP 70,000 - 90,000; Full time

Job summary

A leading AI solutions firm in the United Kingdom is looking for an AI Engineer to fine-tune models and design evaluation frameworks. You'll collaborate with cross-functional teams to ensure AI features are impactful and trustworthy. Candidates should have strong experience in deep learning and proficiency with PyTorch or TensorFlow. This hybrid role offers top-tier compensation and flexible work arrangements.

Benefits

Housing rental subsidies

Quality company cafeteria

Unlimited, flexible time off

Health, dental & vision insurance

Performance-based bonuses

Qualifications

• Strong experience in transformers and fine-tuning methods.
• Proficiency with PyTorch or TensorFlow.
• Skilled in prompt engineering for tone and safety.

Responsibilities

• Fine-tune and adapt AI models using LoRA/QLoRA.
• Engineer prompts and curate datasets.
• Evaluate models with metrics for safety and quality.

Skills

Transformers

Deep learning

Fine-tuning methods

Prompt engineering

Software engineering foundations

Tools

PyTorch

TensorFlow

Job description

Transform Language Models into Real-World Applications

We’re building AI systems for a global audience. We are living in an era of AI transition - this new project team will be focusing on building applications to enable more real world impact and highest usage for the world.

This role is a global role with hybrid work arrangement - combining flexible remote work with in-office collaboration at our HQ. You’ll work closely with regional teams across product, engineering, operations, infrastructure and data to build and scale impactful AI solutions.

Why This Role Matters

You’ll fine-tune state-of-the-art models, design evaluation frameworks, and bring AI features into production. Your work ensures our models are not only intelligent, but also safe, trustworthy, and impactful at scale.

What You’ll Do

• Fine-tune & adapt - Use LoRA/QLoRA to optimize open-source models (LLaMA, Mistral, Gemma)
• Engineer prompts & curates data - Craft prompts and datasets that reflect tone, brand voice, and safety.
• Evaluate models – Build metrics pipelines for perplexity, toxicity, and relevance to ensure safe and high-quality outputs.
• Deploy & monitor – Scale models into production with performance optimization and monitoring for drift.
• Collaborate & deliver – Partner with product, engineering, and design teams to launch user-facing AI features.

What Is It Like

• Like ownership and independence
• Believe clarity comes from action - prototype, test, and iterate without waiting for perfect plans.
• Stay calm and effective in startup chaos - shifting priorities and building from zero doesn’t faze you.
• Bias for speed - you believe it’s better to deliver something valuable now than a perfect version much later.
• See feedback and failure as part of growth - you’re here to level up.
• Possess humility, hunger, and hustle, and lift others up as you go.

Requirements

• Strong experience in transformers, deep learning, and fine-tuning methods (LoRA/QLoRA, SFT, distillation).
• Proficiency with PyTorch (preferred) or TensorFlow.
• Skilled in prompt engineering and dataset curation for alignment with tone, safety, and trust.
• Familiar with evaluation metrics: perplexity, toxicity, relevance.
• Strong software engineering foundations in algorithms, data structures, and clean code practices.

Nice to Have

• Prior work in text generation, moderation, or personalization.
• Experience with RLHF or reinforcement learning in LLMs.
• Contributions to open-source ML projects.

What You’ll Get

• Flat structure & real ownership
• Full involvement in direction and consensus decision making
• Flexibility in work arrangement
• High-impact role with visibility across product, data, and engineering
• Top-of-market compensation and performance-based bonuses
• Global exposure to product development
• Lots of perks - housing rental subsidies, a quality company cafeteria, and overtime meals
• Health, dental & vision insurance
• Global travel insurance (for you & your dependents)
• Unlimited, flexible time off

Our Team & Culture

We’re a densed, high-performance team focused on high quality work and global impact. We behave like owners. We value speed, clarity, and relentless ownership. If you’re hungry to grow and care deeply about excellence, join us.

About Bjak

BJAK is Southeast Asia’s #1 insurance aggregator with 8M+ users, fully owned by its employees. Headquartered in Malaysia and operating in Thailand, Taiwan, and Japan, we help millions of users access transparent and affordable financial protection through Bjak.com. We simplify complex financial products through cutting-edge technologies, including APIs, automation, and AI, to build the next generation of intelligent financial systems.

If you're excited to build real-world AI systems and grow fast in a high-impact environment, we’d love to hear from you.