Job Overview
  • Company

    JaJa Finance Ltd

  • Date Posted

    30-06-2025

  • Location

    London, England, United Kingdom

Senior Data Scientist

About Jaja 


Our Mission: Empowering our customers to buy, borrow, and build—driven by tech, fuelled by data, and built for the future. 

Our Company Values: Care Deeply, Adapt & Thrive, Challenge everything, Go for it! Own it, Make it Simple 


Jaja is an innovative UK based consumer finance business, leading initially with a digital credit card launched in 2018, and a pipeline of consumer finance solutions in the making.  


We are on a mission to redefine the consumer finance experience and liberate customers from needless complexity, wasted time and frustration. Or as we say it, Make Simple.  


We will delight our customers – making the customer experience simpler, more enjoyable, more intelligent – treating customers fairly and giving them more control of their money. 


Why join us?    

This is a chance to make a real impact in a growing business on a mission to change the face of the consumer finance industry forever. 

 

About The Role 

Jaja Finance is looking for a Senior Data Scientist to join our team. Your role will span across the whole lifecycle of model development. That means you are someone who enjoys in equal measures the data wrangling to compose meaningful feature and clean sets, and modelling using Machine Learning.  


You’ll develop and deploy
machine learning models that power real-world decisions — from underwriting to fraud detection to optimise customer conversion. This is an end-to-end role: data wrangling, model development, evaluation, and performance monitoring.
 


As a Data Scientist, you'll play a key role in the end-to-end lifecycle of our advanced machine learning models, working with structured and unstructured data to fuel predictive analytics. You’ll be part of an agile, innovative team, developing cutting-edge solutions that are transforming the world of credit risk. Your work will have a real-world impact, driving smarter decisions and enhancing our customer experience. 

 

Key responsibilities: 

  • Lead your own projects, across the end-to-end lifecycle of model development  
  • Compose the necessary datasets in order to tackle the task at hand  
  • Pre-process/clean the data according to the ML algorithm of your choice  
  • Conduct exploratory data analysis to identify trends, patterns, and insights  
  • Train, tune and evaluate the performance of the model  
  • Build the necessary monitoring in order to measure performance and quickly spot data drift   
  • Collaborate with stakeholders from different functions
    in order to understand their requirements and provide the appropriate solutions
     
  • Actively search for areas where ML solutions could have a big impact on the business  
  • Communicate findings and insights to technical and non-technical stakeholders  
  • Support the rest of the Analytics team by building complex visualisations in Tableau  

 

This role offers
the chance to make a real impact in a growing scale-up on a mission to change the face of the consumer finance industry forever.
 

 

About You 

We’re
seeking a curious, hands-on Senior Data Scientist and the successful candidate must have the right to work in the UK and meet the following criteria:
 

 

Required Skills & Experience: 

  • Bachelor's degree in computer science, Mathematics, Statistics, Business Administration or related field  
  • Advanced knowledge of SQL (joins, aggregations, CTEs and window functions)  
  • Good knowledge of Python, including popular Data Science packages (pandas, matplotlib, seaborn, numpy, sklearn)  
  • Familiarity with what is happening under the hood of popular Machine Learning algorithms  
  • Strong problem-solving skills and attention to detail  
  • Strong communication and collaboration skills  
  • Ability to work in a fast-paced, dynamic environment  
  • Eagerness to make an impact and lead on model delivery  
  • Previous experience developing underwriting or behavioural models for credit extension 

 

Desired: 

 

  • Master's degree in data science/Machine Learning or related discipline  
  • Knowledge of Deep Learning frameworks, ideally Keras/Tensorflow
     
  • Familiarity with software version control (GitHub, bitbucket)  
  • Knowledge of Tableau  
  • Ability to comprehend research papers and possibly apply their solutions  
  • Credit card industry knowledge 

 

What's in it for you?  

  • Competitive salary based on industry benchmarking 
  • Fully flexible remote hybrid working model
     
  • Option to join our Pension Salary Exchange scheme to turbo charge your pension contributions 
  • Participation in our annual bonus scheme  
  • 25 days annual leave (FTE) plus UK bank holidays (with an additional day added for each full calendar year worked, up to a maximum of 30 days). 
  • An extra day off for your birthday each year 
  • Private medical cover through Vitality 
  • 4x life insurance cover 
  • Family-friendly policies with enhanced support 
  • Free access to our confidential Employee Assistance Program 
  • Access to various company perks, competitions and recognition scheme