Machine Learning EngineerUp to £230,000

About the Role

Almedia runs Freecash, a bootstrapped rewards platform with roughly 80 million users, profitable since day one. Their data and ML org is deliberately small, and the models it ships decide which offers and rewards get shown to which users in real time — a direct line from what you build to what the company earns. You'll own that surface end to end: designing and shipping production models, translating the mathematical problems at the core of the business into concrete ML formulations, building the reward and payout structures that balance user motivation with cost sustainability and advertiser value, and diagnosing why an underperforming reward campaign is underperforming.

This is a hands-on role — you'll be in the code, on a small team, with real influence over how the ML infrastructure gets built, from the training pipeline through to the model running on it. The feedback loop is short: build a model, test it, ship it, see the number move, in weeks rather than quarters. Priorities move across reward ranking, personalisation and measurement as the business needs them to, so this suits someone who treats an unfamiliar part of a problem as a chance to dig in rather than a detour from their specialty. They're hiring across a range of seniority, from experienced Senior through to Staff or Principal scope, and backgrounds in adtech, gaming or gambling — or with recommendation and ranking systems, or growth metrics like pLTV, retention and ROAS — land particularly well.

What They're Looking For

• You're genuinely hands-on in production ML, particularly on non-standard problems, and you've shipped models end to end rather than handing them off
• You work across the full stack of a problem: data pipeline, model, and live serving
• You have a strong grounding in statistics — A/B testing, regression, probability — and ideally causal inference and uplift methods
• You want to build ML infrastructure alongside your team, not just use infrastructure that already exists
• You're motivated as much by business impact as by technical elegance, and you'll do the simple high-leverage thing when that's what the business actually needs

About Almedia

Almedia rewards a community of roughly 80 million people for engaging with advertisers' products, through its Freecash platform. They've been profitable from day one, are still bootstrapped, and were ranked the third fastest-growing company in Europe in the FT1000 2025. Around 170 people today across Berlin and a new London office, with plans to roughly double. London is their newest site, and data and ML is one of the first functions being built there.