Senior Machine Learning Engineer, Lokalise

• This is a role for someone who thrives in complex systems, has a drive for engineering excellence, and enjoys supporting others to succeed
• 4+ years of experience building and operating backend systems in production
• Strong proficiency with Python, FastAPI, and Pydantic
• Solid understanding of microservice architecture, scalable distributed systems, and observability, with familiarity using tools like OpenTelemetry, Grafana, or Datadog to monitor both general system health and LLM-specific metrics like latency, token usage, and model performance
• Hands-on experience with prompt engineering in production
• Familiarity with CI/CD, containerisation, and cloud deployment
• Strong sense of ownership

Desirable

• We’re looking for a Senior Machine Learning Engineer to join our growing AI team
• You’ll be the technical owner of the systems that power LLM-based localization features — designing reliable, scalable, and observable services from the ground up
• You’ll also partner across disciplines to support ML operations and data infrastructure — enabling experimentation and continuous improvement
• Build and own LLM-powered back end services using FastAPI, Pydantic, etc. — ensuring they are scalable, observable, and easy to extend
• Design infrastructure that enables rapid experimentation with LLMs, including A/B testing, feature flagging, and usage analytics
• Integrate and maintain LLM observability tooling (e.g., LiteLLM, Langfuse) to monitor quality, cost, and performance of model calls
• Collaborate with Data and ML Scientists to productionize workflows, share feedback, and continuously improve experimentation speed
• Ensure systems are reliable and deployable with strong CI/CD practices, including instrumentation and alerting
• Contribute to team culture through pairing, mentoring, and sharing learnings to help others grow
• Stay connected to the product by understanding our users' needs, localization workflows, and broader industry trends