Senior Machine Learning Engineer

We're building the intelligence layer that turns our customers' marketing data into outcomes — predictions and actions that help small businesses reach the right people, at the right time, on the right channel, without a full marketing team.

Our ML team is young and shipping fast. We're now hiring its senior technical anchor: the engineer whose judgment the team's models get checked against before they touch production. We work remote-first across ~40 countries with a lot of autonomy and a strong bias toward shipping.

What you'll work on

• Own the correctness of predictive models built on billions of behavioral events — engagement prediction, send-time and audience optimization, list health, segment discovery
• Be the review backstop for the team on data representativeness, sampling, labeling, and evaluation design — the places where models go quietly wrong
• Take models from honest offline evaluation to disciplined production operation: CI gates, drift monitoring, A/B testing, retraining, serving cost
• Bring deep LLM training experience as we fine-tune and self-host our own models, including evaluation and guardrails for systems that take real actions on real accounts
• Level up the engineers around you through review and example

What we expect from you

• 5–8+ years shipping ML models to production and owning them there
• A sharp eye for silent failure modes — representativeness and population bias, sampling problems, label noise, temporal leakage, calibration — and a record of catching them before they shipped
• Deep applied fundamentals on imbalanced and time-series problems
• Mature production MLOps habits: monitoring, A/B testing, retraining pipelines, cost discipline
• Hands-on LLM fine-tuning beyond adapters — supervised fine-tuning at minimum, preference optimization or RL a strong plus — ideally on self-hosted GPUs
• Fluency in Python and the modern ML stack (scikit-learn, gradient boosting, pandas/Polars, PyTorch)
• Comfort as a senior IC on a small team, working remote and async
• Based within EMEA region 

Bonus points

• Large-scale event/columnar stores and relational databases at scale
• Revenue, attribution, or uplift modeling
• You've been the first senior engineer on a young ML team before
  
  

What we offer

• Yearly gross salary: 75k-100k EUR/year
• Remote-first culture
• International health insurance
• Company-paid retreats once a year
• 31 days of vacation (including public holidays)
• 12 paid sick days - Parents can use them to care for their sick children
• 4 creative days - One paid day off per quarter to do something creative and fun
• 12 parental days - One paid day off each month to treasure time with your children
• Parental leave: 100% paid leave (3 months maternity, 1 month paternity) or adoption
• Parenting budget of $1000
• Joy Budget - Annual allowance starting at $1,000 per year and increasing over time
• MacBook for work