Senior ML Engineer

We are hiring for a rapidly growing company that provides marketing automation tools, focusing on building an intelligence layer that empowers small businesses to achieve better marketing outcomes through data-driven predictions and actions. This is an opportunity to join a dynamic, remote-first ML team and play a pivotal role in shaping the future of their predictive capabilities.

The Role

• Own the correctness of predictive models processing billions of behavioral events for engagement prediction, send-time and audience optimization, and list health.

• Act as the primary reviewer for the team, ensuring data representativeness, sampling, labeling, and evaluation designs are robust.

• Manage the transition of models from offline evaluation to production, including CI gates, drift monitoring, A/B testing, and retraining.

• Leverage deep LLM training experience for fine-tuning and self-hosting models, focusing on evaluation and guardrails for real-world applications.

• Mentor and elevate other engineers on the team through code reviews and knowledge sharing.

What You'll Need

• 5–8+ years of experience shipping and owning ML models in production.

• A proven ability to identify and rectify silent failure modes such as bias, sampling issues, and temporal leakage.

• Deep understanding of applied fundamentals for imbalanced and time-series problems.

• Mature MLOps practices, including monitoring, A/B testing, retraining pipelines, and cost management.

• Hands-on experience with LLM fine-tuning, ideally on self-hosted infrastructure.

• Fluency in Python and the modern ML ecosystem (scikit-learn, gradient boosting, pandas/Polars, PyTorch).

What's On Offer

• Competitive annual salary (€75,000 - €100,000) plus additional benefits.

• A remote-first culture with significant autonomy and a bias towards shipping.

• Company-paid global retreats and a generous vacation policy.

• Comprehensive parental leave and a dedicated parenting budget.

Apply via Haystack today!