Senior Applied Data Scientist (AI)

TL;DR

Senior Applied Data Scientist (AI): Developing and validating knowledge tracing and longitudinal learner models to define operational mastery with an accent on computational psychometrics, calibration, and fairness. Focus on building robust training pipelines for noisy learner data and productionizing these models into scalable services.

Location: Hybrid in Budapest, Hungary

Salary: HUF 1.8M – 2.2M per month

Company

hirify.global creates intuitive products that simplify learning and personal development to help educators and students learn together.

What you will do

• Design and build knowledge tracing and longitudinal learner models to support mastery and progression features.
• Define operational constructs, model targets, and evaluation criteria for "mastery" and "progression".
• Develop robust training and scoring approaches for noisy, incomplete, and evolving learner interaction data.
• Lead evaluations for model validity, calibration, fairness, stability over time, and interpretability.
• Partner with engineering to productionize learner models into reliable services, including deployment and monitoring.
• Translate learning theory into scalable product systems and communicate model assumptions to stakeholders.

Requirements

• 6+ years of experience in applied ML, data science, or applied research with models shipped into real products.
• Strong depth in knowledge tracing, sequence modeling, probabilistic modeling, temporal modeling, Bayesian approaches, or psychometrics.
• Working understanding of computational psychometrics for rigorous measurement of constructs.
• Ability to evaluate models based on calibration, uncertainty, fairness, and robustness beyond predictive accuracy.
• Experience working with longitudinal data and designing stable, interpretable models over time.
• Strong Python and ML stack skills for implementing and iterating on modeling pipelines.

Nice to have

• Deep experience with Item Response Theory (IRT) or educational measurement.
• Experience with learning science or adaptive learning systems.
• Track record of building customer-facing learner progress or mastery products.
• Experience combining structured knowledge representations (concept graphs) with learner models.
• Experience partnering with platform teams to run models at scale on AWS.

Culture & Benefits

• Competitive compensation and participation in the company ownership program.
• Flexible work culture with remote and hybrid collaboration options.
• Generous time off, including local holidays and an annual "Dim the Lights" recharge period in December.
• Comprehensive wellness programs and mental health support.
• Learning and development resources, including professional development tools and tuition reimbursement.
• Employee recognition through the Motivosity program.