# Senior Principal Data Scientist (Fulfilment) **Company**: Grab **Location**: Singapore **Experience**: senior **Job type**: full-time **Category**: Data Science **Industry**: Technology **Apply**: https://jobs.smartrecruiters.com/Grab/744000146514470-senior-principal-data-scientist-fulfilment-?utm_source=yubhub.co&utm_medium=jobs_feed&utm_campaign=apply **Canonical**: https://yubhub.co/jobs/job_ae91de16-102 ## Description Grab is Southeast Asia's leading superapp, providing services such as food delivery, financial management, and ride-hailing. The Fulfilment Tech Family builds the systems that power Grab's marketplaces across Southeast Asia, designing real-time, distributed systems and Machine Learning (ML) solutions that process hundreds of millions of requests each day. We are looking for a Senior Principal Data Scientist to lead our shift toward automated marketplace optimization, advancing how we use data and ML to automate pricing, dispatch, and supply management decisions. **Responsibilities** - Design and implement end-to-end RL systems that combine model-based RL, offline RL, simulation, and online learning into a unified training pipeline. - Build latent world models and marketplace state representations that capture supply-demand interactions, location-based patterns, and behavioural signals from users and drivers. - Develop systems that optimize across multiple marketplace levers simultaneously,pricing, dispatching, and supply repositioning,to expand the set of achievable outcomes for the business. - Create policy evaluation frameworks and establish monitoring systems that allow safe deployment of new decision-making policies in production. - Fine-tune open-source large language models on domain-specific data to build capabilities for prediction, reasoning, and simulation within marketplace applications. - Design and implement training strategies for language models, including supervised fine-tuning, preference-based alignment, and iterative improvement methods. - Work with data engineers and backend engineers to integrate RL and LLM systems into real-time production environments serving millions of users. **Qualifications** - PhD in Computer Science, Operations Research, Applied Mathematics, or related field with at least 10 years of experience. - Proficiency in RL fundamentals, including Markov Decision Processes, stochastic control, and reward design trade-offs. - Experience building production ML/ RL systems with online learning or simulation-based optimization. - Knowledge in world models and sequential modelling, including latent dynamic models (RNNs, transformers, state-space models) and representation learning for complex systems. - Hands-on experience fine-tuning large language models in production, including supervised fine-tuning and at least one preference-based alignment method (RLHF, DPO, or GRPO). - Experience with distributed training frameworks, such as DeepSpeed, FSDP, or Megatron-LM. - Proficiency in Python and ML frameworks (PyTorch or TensorFlow). - Experience with scalable computing platforms, such as Spark or Ray. **Benefits** - Term Life Insurance and comprehensive Medical Insurance. - GrabFlex, a benefits package that suits your needs and aspirations. - Parental and Birthday leave, and Love-all-Serve-all (LASA) volunteering leave. - Confidential Grabber Assistance Programme. - FlexWork arrangements, such as differentiated hours. ## Skills ### Required - Reinforcement Learning - Machine Learning - Large Language Models - Distributed Training Frameworks - Python - PyTorch - TensorFlow - Scalable Computing Platforms --- Source: [Apply at jobs.smartrecruiters.com](https://jobs.smartrecruiters.com/Grab/744000146514470-senior-principal-data-scientist-fulfilment-?utm_source=yubhub.co&utm_medium=jobs_feed&utm_campaign=apply)