Senior AI Engineer (GenAI)

Join ABC Fitness, the leading technology provider for the fitness industry!

Join ABC Fitness and become part of a culture that’s as ambitious as it is authentic. Let’s transform the future of fitness—together!

Our Values

Best Life

We believe great work begins with great people. That’s why our culture is built on respect, trust, and belonging. We create an inclusive environment where every team member can bring their authentic self to work—because diverse perspectives drive innovation and meaningful impact.

Growth Mindset

We are doers, thinkers, and dreamers. At ABC Fitness, your growth is our investment. Through continuous learning, mentorship, and professional development opportunities, we empower you to reach new heights—personally and professionally.

One Team

From day one, you’ll be part of a team that collaborates, celebrates, and cares. We move fast, support one another, and have fun along the way. Because when you thrive, we all thrive.

We’re looking for a senior individual contributor who can independently lead delivery of an LLM feature area, including eval strategy and production readiness.
 

ABOUT THE TEAM

The AI Engineering team builds and scales GenAI-powered experiences across ABC’s fitness technology platform—turning messy, real-world workflows into reliable, observable, production systems. We partner closely with Product, Design, and Engineering to ship AI features that are accurate, fast, cost-aware, and safe.

At ABC, we love entrepreneurs because we are entrepreneurs. We roll our sleeves up, we act fast, and we learn together.
 

ABOUT THE ROLE

As a Senior AI Engineer (GenAI), you’ll build end-to-end LLM applications, from prototyping prompts and agentic workflows to production-grade services with evaluation, monitoring, and iteration loops. You’ll work on agent orchestration (e.g., Lang Chain/Lang Graph-style patterns) and establish LLM evaluation frameworks so we can confidently ship improvements.

We’re interested in candidates who are excited to move “up the stack” into production AI engineering, owning not just modeling ideas, but the full system: orchestration, evaluation, deployment, and continuous improvement.
 

WHAT YOU’LL DO

• Build and ship LLM-powered product capabilities end-to-end: APIs, orchestration logic, integrations, and production rollouts.
• Design and implement agentic workflows (tool use, planners/routers, multi-step reasoning, handoffs, memory/state management) using modern orchestration frameworks (e.g., LangChain / LangGraph-style).
• Develop strong prompting + context engineering practices, including prompt versioning and experimentation (e.g., A/B testing approaches).
• Build evaluation harnesses for LLM apps: curated test sets, scenario-based evals, automated checks, offline/online quality metrics, human review loops, regression gates, and release criteria for model/prompt/workflow changes.
• Implement safety and reliability patterns for LLM systems, including guardrails, tool permissions, prompt-injection awareness, fallback handling, and secure data handling.
• Own production readiness for AI features, including rollout plans, monitoring, incident response inputs, performance tuning, and post-launch iteration.
• Experience designing clean API/tool interfaces for LLM workflows, including structured inputs/outputs, schema validation, error handling, retries, and observability.
• Collaborate with platform/infra teams to deploy on AWS or GCP, ensuring reliability, scalability, latency, and cost controls.
• Instrument systems for observability (quality, latency, token/cost, errors) and create feedback loops to improve model and system behavior over time.
  Work cross-functionally with Product/Design to translate ambiguous problems into measurable outcomes and shippable iterations.
• Use AI-assisted development tools responsibly to accelerate coding, testing, debugging, documentation, and experimentation while maintaining strong engineering standards for review, quality, security, and maintainability.
   

WHAT YOU’LL NEED

• 5-8 years of professional experience in software engineering, applied ML, data science engineering, or AI product engineering.
• Strong Python skills, and experience building backend services (e.g., Flask/FastAPI) and integrating with REST APIs.
• Practical understanding of LLMs/SLMs and how they behave in production (hallucinations, prompt sensitivity, latency/cost tradeoffs).
• Hands-on experience building LLM applications (RAG, tool use, agents, workflow orchestration), with the ability to demonstrate end-to-end ownership from prototype → production → measurement → iteration.
• Awareness of production AI risks such as hallucinations, prompt injection, unsafe tool use, data leakage, privacy concerns, and model/output drift.
• Experience with cloud infrastructure (AWS or GCP) and shipping production workloads (containers, deployments, monitoring).
• Strong engineering fundamentals: testing, debugging, performance thinking, and clean, maintainable design.
• Excellent communication skills and ability to collaborate effectively in fast-paced, agile environments.
• Practical experience using AI-assisted engineering tools such as Cursor, GitHub Copilot, Claude, ChatGPT, or similar tools to improve developer productivity without compromising code quality.

AND IT’S GREAT TO HAVE

• Experience with LLM evaluation/observability tooling (e.g., experiment tracking, tracing, prompt/version management, continuous evaluation).
• Familiarity with vector databases / retrieval systems and relevance tuning (RAG patterns, embedding selection, chunking strategies).
  Prior work on agent reliability patterns: guardrails, tool error handling, fallbacks, and human-in-the-loop designs.
• Experience with CI/CD, Docker/Kubernetes, or infrastructure-as-code.
• Bachelor’s degree in computer science, Engineering, or equivalent practical experience is preferred

Please note that the salary information shown below is a general guideline only and based on employees in Poland and may be different in other countries. Salaries are based upon candidate experience, qualifications, and location, as well as market and business considerations. Our pay range for Poland based candidates for this position is zł275,000 - zł310,000 PLN annually. Your recruiter can share more about the specific salary range for the job location during the hiring process. Also, certain positions are eligible for additional forms of compensation such as bonuses and commissions.
 

Why This Matters 

ABC Fitness is building toward an AI-native future by developing agentic experiences, intelligent workflow automation, and platform-level capabilities that turn data and models into action. The work spans recommendation systems, orchestration, embedded intelligence, and scalable AI-powered product experiences that directly influence how customers acquire, serve, retain, and grow their members. It is an opportunity to build applied AI in production, at meaningful scale, on problems that matter to customers every day. 
 

At ABC Fitness, we don’t just build technology—we build communities and transform lives. Your work matters here, your growth is supported, and your voice is heard. We welcome diverse talent and encourage you to apply, even if you don’t meet every requirement.

ABC’S COMMITMENT TO DIVERSITY, EQUALITY, BELONGING AND INCLUSION: 

ABC is an equal opportunity employer committed to diversity, equity, and inclusion. We strive to create a workplace where every employee, client, and partner feels valued, inspired, and empowered to reach their full potential. For us, inclusion isn’t just the right thing to do—it’s a business imperative. Learn more at abcfitness.com

About ABC Fitness

ABC Fitness is the #1 software provider for fitness businesses of any size, all around the world. Supporting 30K clubs, 650K coaches, 40M members, and processing more than $12B in payments every year, ABC Fitness provides scalable, data-driven solutions to simplify club management and engage members and clients.

From personal trainers, boutique studios, and gyms, to international franchise health clubs, ABC Fitness will move your business forward through technology and industry insights. Innovation is at the center of everything we do, across ABC Glofox, ABC Ignite, ABC Trainerize, and ABC Evo. Let's make your fitness vision a seamless reality, together. Learn more at abcfitness.com.

#LI-REMOTE

If you like wild growth and working with happy, enthusiastic over-achievers, you'll enjoy your career with us!