Senior Machine Learning Engineer

• Join a two-person ML team scaling a forecasting system from a handful of clients to hundreds. • Own client launches end to end from validating data and selecting models through to going live and monitoring performance. • Work on half-hourly demand predictions across diverse targets for multiple restaurant chains in a complex environment with feedback loops and high variability.

• Have production ML experience with a track record of deploying ML systems that handle messy data, fail gracefully, and need monitoring. • Have strong ML fundamentals and be able to reason about trade-offs in practice, explain the why behind feature and model choices, and make good judgement calls. • Have client-facing deployment experience and have personally owned an ML deployment end to end and be comfortable on calls with non-technical stakeholders. • Have strong programming skills in Python including the ML and scientific Python stack such as numpy and scikit-learn. • Use AI development tools such as Claude Code, Cursor, or Copilot daily as your default working mode.

• Have experience with forecasting, time-series, or demand-planning including lag features, calendar effects, and evaluation integrity. • Have experience with the Sona stack including Python, scikit-learn, MLflow, Docker, and GCP. • Have experience working in a small team where ownership is wide and context-switching is normal.

• Own client launches end to end including validating data, selecting models, running UAT, going live, and monitoring performance afterwards. • Join client calls, build relationships, and understand what actually matters on the ground. • Scale the forecasting system from a handful of clients to hundreds. • Work with industry experts to understand what is happening in client businesses and the realities of working there. • Take machine learning projects from business idea to deployed production system. • Handle messy data, build systems that fail gracefully, and ensure robust monitoring.

Sona is one of the most exciting B2B SaaS companies in the UK right now. The company has raised over $100 million from world-class investors and has grown revenue by 400% in 2023 alone. Two of the three founders, Oli Johnson and Ben Dixon, previously spent six years building Catapult, a gig platform for hospitality and retail, while Steffen Wulff Petersen came from Rocket Internet, where he helped launch Lazada, HelloFresh and Payleven. That domain expertise is a genuine differentiator: Sona is not a generic scheduling tool bolted onto HR. It is built from the ground up for complex, multi-site enterprises with hundreds or thousands of frontline staff. What stands out on Glassdoor (4.6/5 from 26 reviews, 88% recommend, 94% positive business outlook) is how consistently employees praise the team culture, the benefits and the pace of growth. The compensation sub-score is a remarkable 4.9/5. Sona offers genuinely strong benefits for a startup: Bupa health insurance, 25 days holiday plus 10 flexible public holidays (with an extra day per year of service), enhanced parental leave (26 weeks full pay for primary parents, 8 weeks for secondary), share options, pension matching up to 5%, twice-yearly team retreats and a quarterly £200 learning budget. The main things to be aware of: this is a fast-paced startup where priorities shift quickly; some reviews mention long hours and pressure around headcount management; and the team is still relatively small, at around 150 people. But with a fresh $45 million Series B led by N47, US expansion underway, and the recent launch of Forge, an enterprise AI application builder that lets customers create custom software on top of Sona's platform, the company is at a genuinely exciting inflexion point.

• Earn £95,000 to £110,000 salary plus share options. • Work fully remote within European timezones. • Take 35 days annual leave including 25 standard days plus 10 flexible public holiday days. • Receive an extra day of leave for every year of service. • Receive pension contributions matched up to 5%. • Access comprehensive health insurance. • Benefit from enhanced parental leave and pay. • Receive a co-working space stipend if based outside London. • Attend bi-annual all-expenses-paid team retreats. • Receive the latest MacBook and equipment budget for home office. • Access a professional development budget and unlimited free books.

Sona is building the next generation of AI-native frontline workforce management. The end-to-end platform covers Scheduling, HR, Payroll, and Communications giving the largest frontline organisations everything they need to staff more intelligently and empower their teams. In under 5 years Sona has impacted over 100k frontline workers, grown to 140+ team members, and secured over $100M in funding including a Series B led by N47 alongside Felicis, Northzone, and Gradient Ventures.