Senior Data Science

About The Position

Justt is the world leader in fighting illegitimate chargebacks on behalf of merchants. Our chargeback mitigation solution uses smart technology to create a hands-off experience for merchants, while providing the highest overall success rates in the industry.

As the first senior data scientist in the company, you will solve complex financial business problems and lead the research efforts using modern machine learning models that will directly impact the company’s business goals. Your responsibility will truly be end-to-end, in terms of data annotation, data analysis, feature engineering, modeling, model productionalization, support and optimization of model performance.


  • Lead end-to-end ML projects from conceptualization to production.
  • Partner with leadership and product managers to understand the business and product needs. 
  • Communicate research results to business and product stakeholders, and clients.
  • Collaborate with data engineers and machine learning engineers.
  • Enable business and product stakeholders to be data driven, and solve problems that in turn allow the company to push the boundaries of business KPIs.
  • Monitor model & data performance, taking into account chargeback reversal decisions, that may arrive up to 120 days later.
  • Identify and address gaps in processes, data-science habits, data-science code reviews, data integrity and validation, unit testing, documentation, and continually improve the company’s processes and standards.


  • Bachelor's degree in Computer Science or related technical field, or an equivalent practical experience.
  • 2+ years development in Python or one other general purpose programming language such as Java.
  • Proven experience solving complex business and product problems with data science tools & libraries, modern machine learning models, or statistical and probabilistic modeling.
  • Can plan, collaborate, prioritize and execute on their research plans.
  • A brainstormer that loves a good discussion about new ideas with fellow data scientists and engineers.
  • Independent learner, imaginative and motivated to run on their own, who cares about novel research and papers, works well with others, with a “can do” approach.
  • A communicator that can tell their research story and make a strong case about the results validity.
  • Experience with SQL or similar query language
  • Speaking and writing English fluently.

Preferred qualifications:

  • Experience in FinTech and specifically working with Payments data and delayed feedback.
  • An advanced academic degree.
  • Strong programming skills.
  • Experience developing on remote machines such as AWS, GCP, Azure.
  • Community or side projects (please point us to your public GitHub or Kaggle accounts)
  • Thought Leader.

Apply for this position

Choose your cookie settings

You can control how Justt uses cookies on each device and browser that you use to browse our website. These cookie settings only apply to the device and browser you’re currently using.


Cookies used to make our site work for you,

securly and safely


Cookies used to understand how you interact with

our site, and how to improve it for future visits


Cookies used to improve your experience with our site, such as language and country selection


Cookies used to offer Justt’s services

across other websites and platforms

Confirm Cookies
Start now. Win back lost revenue

Find out why Justt is the right solution for your business.

    Chargebacks per month

    • Under $5,000
    • Under $50,000
    • Under $100,000
    • Over $100,000