Job Application for Senior/Lead Machine Learning Engineer (AdTech) at Flo Health

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We’re very proud of our achievements:

In July, we secured a $200M investment led by General Atlantic to help revolutionise women’s health, and became the first purely digital consumer women’s health app to achieve unicorn status! 🦄

We’ve had 380M+ downloads, have almost 70M monthly users, are #1 by installs in the iOS Health category, hit 4.9 stars on the App Store (3M+ reviews), are backed by 9 VCs, had a 40% revenue increase last year, and topped a valuation of $1B.

We’re a growing, ambitious HealthTech business building the essential digital health partner of tomorrow to empower women, girls, and people who menstruate with the knowledge and support they need to stay well and live better.

Our cycle, ovulation and pregnancy tracking, educational content and anonymised community platform have been trusted for years by millions to help them feel more in control of their health every day.

Now, we’re harnessing the power of data analytics and AI to build a smarter future, one where we all know our bodies better, with an aim to become the essential health partner to women worldwide.

The Job

We are Flo, the world’s most popular female health app! Our engineers aren’t just building a better product; they’re making the world a better place by improving female health.

Flo is at the forefront of revolutionizing the AdTech landscape by utilizing advanced machine learning and data analytics. Our mission is to empower marketing and finance teams with predictive insights that enhance decision-making related to user acquisition (UA), campaign evaluation, budgeting, and more. We are seeking a talented Machine Learning Engineer to join our dynamic AdTech ML team. In this role, you will help us develop robust models to predict lifetime value (LTV) and other critical metrics.

Your Experience

Must have:

4+ years of experience in machine learning.
Strong knowledge of classical machine learning and neural networks.
Proven experience deploying ML models in production systems.
Strong computer science foundation.
Strong Python programming skills.
Experience building and managing data pipelines to operate on Big Data using distributed computing or streaming frameworks.
Excellent communication skills and ability to collaborate with diverse teams.
Ability to work in ambiguity and on high-risk systems.
Experience navigating high-impact systems under challenging circumstances.

Nice to have:

Experience with predictive LTV models.
Experience with forecasting models.
Experience with reinforcement learning models.
Experience with online testing.
Experience with any SQL syntax.

What you'll be doing

You'll be responsible for:

Developing ML models end-to-end: from initial experiments to deployment and ongoing maintenance.
Driving company growth in the AdTech domain by building ML solutions, focusing on LTV prediction and other KPIs critical to User Acquisition, Finance, and Marketing teams.
Designing, implementing, and ensuring scalable, production-ready, and high-performance solutions.
Building and maintaining data pipelines for efficient preprocessing, feature engineering, and model training.
Collaborating with key stakeholders, such as UA and Finance teams, to define requirements, interpret predictions, and integrate insights into workflows.
Partnering with product and engineering teams to ensure seamless model integration, deployment, and accuracy in production systems.
Calibrating models to meet business requirements for accuracy, efficiency, and scalability at cohort and individual prediction levels.
Developing and generalizing calibration methodologies to align predictions with cohort-level aggregates.
Exploring and implementing new ML use cases, such as budget allocation optimization, campaign optimization, and spend forecasting.
Establishing monitoring systems for model performance and retraining processes.
Diagnosing and resolving issues in production models.

#LI-Hybrid #LI-LM12

Salary Range - per year

£80,000 - £150,000 GBP

Ranges may vary depending on your skills, competencies and experience.

Reward

People perform better when they’re happy, paid well, looked after and supported.

On top of competitive salaries, Flo's employees have access to:

A flexible working environment with the opportunity to come into the office and work from home
Company equity grants through Flo’s Employee Share Option Plan (ESOP)
Paid holiday and sick leave
Fully paid female health and sick leave, in addition to holiday and regular sick leave
Workations - an opportunity to work abroad for two months a year
Six months paid maternity leave, and one months paid paternity leave (subject to qualifying conditions) inclusive of same-sex and adoptive parents
Career growth, progression, and learning development resources
Annual salary reviews
Unlimited free premium Flo subscriptions
A whole host of other benefits (health/pension/social schemes)

Our Culture

We’re problem solvers, we’re adaptable, we’re empathy driven and results led.

People here like working in a fast-paced, multi-national, multi-cultural and ever changing environment. Everyone has an impact on a powerful mission, and is happy to roll their sleeves up to ideate solutions and put them in place. Being part of a growing business means that sometimes it's not easy and we work hard, but our mission is always at the forefront of what we do.

Diversity, Equity and Inclusion

The strength of our workforce is in the diverse backgrounds of our employees, and Flo is committed to applying its equal opportunities policy at all stages of recruitment and selection. This means recruitment and selection of talent into Flo Health companies is only based on individual merit and qualifications directly related to professional competence. Shortlisting, interviewing, and selection will always be carried out without regard to gender identity or expression, sexual orientation, marital or civil partnership status, color, race, nationality, ethnic or national origins, religion or beliefs, ancestry, age, veteran status, mental or physical disability, medical condition, pregnancy or maternity status, trade union membership, or any other protected characteristics.

By applying for the above role, you confirm that you have reviewed our privacy notice for job applicants: https://flo.health/privacy-policy-for-job-applicants

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Senior/Lead Machine Learning Engineer (AdTech)

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