
Vikram Kaviya
Verified Expert in Engineering
Data Scientist and Developer
Udaipur, Rajasthan, India
Toptal member since June 2, 2026
Vikram is a senior data scientist and ML engineer with 8 years of experience leading end-to-end AI initiatives. He specializes in LLM alignment (DPO, GRPO), custom LLM orchestration, and extreme multi-class classification (100,000+ categories). Backed by a strong data engineering foundation, Vikram excels in inference efficiency, deploying optimized generative models and scalable search solutions using vLLM, Triton, and Elasticsearch.
Portfolio
Experience
- Python - 8 years
- PyTorch - 7 years
- Natural Language Processing (NLP) - 7 years
- Elastic - 5 years
- Reinforcement Learning from Human Feedback (RLHF) - 3 years
- Generative Artificial Intelligence (GenAI) - 3 years
- Retrieval-augmented Generation (RAG) - 3 years
- Agentic AI - 2 years
Preferred Environment
Visual Studio Code (VS Code), JupyterLab, Cursor AI
The most amazing...
...thing I've built is a custom LLM orchestration framework standardizing Claude, GPT, and tool-calling via a strict Python class schema.
Work Experience
Senior Data Scientist
Knowdis Data Science
- Engineered a custom LLM orchestration framework and provider-agnostic SDK, standardizing the LLM lifecycle and implementing stateful tool loops for reproducible execution, reducing new feature development time by 50%.
- Developed a dynamic error-simulation engine for synthetic pre-training that improved spelling correction accuracy by 6% to 7%, alongside architecting a GRPO latent reasoning pipeline with Phi-4 SFT distillation.
- Engineered a compute-efficient incremental learning pipeline for large-scale multi-class product classification across 100,000+ categories, maintaining over 90% accuracy during client audits.
- Architected an Elasticsearch indexing pipeline for 30+ million product images via WebDataset, bypassing file I/O bottlenecks. Engineered a diff-based backfill system using Painless scripts to maintain index freshness.
- Optimized Vision-Language Model (VLM) inference utilizing AWQ quantization for automated image description generation, and engineered a "VLM-as-a-judge" framework to evaluate search retrieval accuracy.
- Engineered an inference profiling library acting as a quality gate for 15+ client models. Automated gRPC/HTTP load testing across internal and client QAT servers, evaluating latency quantiles up to 32 concurrent requests (8 baseline).
Machine Learning Engineer
Leena AI
- Boosted BERT ranking accuracy from 0.85 to 0.89 by engineering a novel guided incremental training pipeline that utilized soft labels and optimized data cleaning.
- Led Supervised Fine-Tuning (SFT) and Direct Preference Optimization (DPO) of GPT2-XL for intent-free HR extractive question answering. This improved accuracy from 0.73 to 0.80 and was deployed via Text-Generation-Inference(TGI).
- Architected Spanish and Arabic bi-encoder pipelines utilizing online hard triplet loss. This was supported by incremental indexing and Celery-based shadow testing for offline evaluation.
Data Scientist
Paytm
- Engineered an SMS classifier utilizing fastText and XGBoost for transactional data with regex entity extraction. Built a Passbook view by aggregating transactional SMS data via PySpark on Transient EMR and MongoDB.
- Architected a deep parsing PyTorch model for credit card bill entity extraction, training on class and candidate embeddings to achieve 0.9888 accuracy and an AUC exceeding 0.94 across every class.
- Developed real-time streaming analytics features, including IP-to-location mapping, bounce rate, and time-on-page, utilizing Flink and Druid for an in-house, Google Analytics-style data engine.
- Engineered an Airflow-based Transient EMR framework to dynamically provision and terminate ephemeral clusters for ETL jobs, minimizing onboarding effort and saving thousands of dollars over on-premise Hadoop clusters.
Experience
Large-scale Product Visual Search and Ingestion Pipeline
This pipeline applied targeted conditional updates using Painless scripts, serving as the primary index synchronization mechanism to maintain data freshness. On the inference side, I optimized Vision-Language Model (VLM) deployments using AWQ quantization to automate high-throughput image description generation. Finally, I built a robust "VLM-as-a-judge" evaluation framework to continuously monitor and score the retrieval accuracy of the visual search system.
Agentic eCommerce Product Onboarding Engine and Orchestration SDK
Extreme Product Category Classification System
I subsequently extended the framework to process structured metadata (titles and specifications) by building a two-stage retrieval and LLM reranking architecture. This system ensembles three specialized retrievers to heavily prune the search space before passing candidates to a Qwen-V3 model for final refinement. By integrating hierarchy-aware logic into the pipeline, the system achieved a 50% reduction in gross search irrelevance.
Generative Search Query Correction for eCommerce
Education
Bachelor's Degree in Mathematics and Computer Science
Indian Institute of Technology, Guwahati - Guwahait, India
Certifications
Reinforcement Learning
Coursera
Natural Language Processing
Coursera
Deep Learning
Coursera
Skills
Libraries/APIs
PyTorch, vLLM, Hugging Face Transformers, PySpark, XGBoost, MLlib
Tools
Elastic, Claude, Celery, TorchServe, Apache Airflow, Visual Language Models (VLMs)
Languages
Python, Scala
Storage
PostgreSQL, MongoDB
Frameworks
LangGraph
Paradigms
Parallel Computing
Platforms
Visual Studio Code (VS Code), Docker, Apache Flink
Other
Natural Language Processing (NLP), Machine Learning, Artificial Intelligence (AI), Architecture, AI Model Training, FastAPI, Large Language Models (LLMs), Reinforcement Learning from Human Feedback (RLHF), Generative Artificial Intelligence (GenAI), Retrieval-augmented Generation (RAG), Agentic AI, AI Agents, Prompt Engineering, Programming, Probability Theory, Algorithms, Optimization, Calculus, JupyterLab, Cursor AI, Neural Machine Translation, EMR, fastText, Reinforcement Learning, Deep Learning
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