Staff Machine Learning Engineer

Overview

Job Description

Responsibilities

• - Own and build core optimisation systems: Design, implement, and operate ML and optimisation models that power pricing, matching, and allocation within Rosso and related systems, from research through to production.
• - Solve complex applied problems: Develop linear programming and optimisation solutions for batch and near–real-time use cases, balancing cost, risk, portfolio constraints, and commercial outcomes.
• - Ship production-grade models: Build and maintain end-to-end ML and optimisation pipelines in the cloud (AWS preferred), ensuring robustness, explainability, and operational reliability.
• - Develop core IP in-house: Replace third-party logic with high-quality internal implementations, iterating quickly as product and market understanding evolves.
• - Collaborate and influence: Work closely with product, engineering, and commercial teams to translate business needs into effective technical solutions, communicating clearly with non-technical stakeholders.
• - Raise engineering standards: Contribute to best practices in modelling, experimentation, and code quality, and provide informal mentorship to junior engineers and data scientists.

Required Skills

• - Strong optimisation background: experience with linear programming, operations research, or constrained optimisation in real-world systems.
• - Hands-on ML / data science experience: proven ability to build and ship models that matter.
• - Production mindset: experience designing, deploying, and maintaining cloud-based ML or optimisation systems.
• - First-principles thinking: comfortable working in ambiguous, greenfield problem spaces.
• - Strong Python skills and experience with the standard data science stack.
• - Commercial awareness: understands how technical decisions translate into business impact.

Benefits

• - Competitive salary - our current band for this role is £105,000 or equivalent in local currency. We review salaries twice a year using real-time market data, with transparent, consistent pay for the same role and level.
• - Stock Options - everyone on the team has ownership in our mission.
• - 25 days holiday + public holidays - Swap public holidays for ones that matter most to you. Plus, get an extra day off for your birthday 🎉.
• - Remote & flexible working - We’re fully remote with clear core hours, and no internal meetings on Friday afternoons.
• - Home working & wellbeing budgets: Up to £1,200 / €1,200 annually to upgrade your remote setup (co-working passes, equipment, etc.). Up to £150 / €150 monthly on anything that supports your wellbeing - from therapy to gym memberships to meditation apps.