Machine Learning & Deep Learning Portfolio
Context: Delivered while working Full-Time (ARGO DATA) + completing MS CS (UT Austin)
This portfolio showcases my expertise in machine learning and deep learning, from foundational research to production-scale systems serving hundreds of users.
🧠 2025: RL for Mathematical Reasoning (Gemma-3 Fine-tuning)
Signal: RLHF / Post-Training / Foundation Models
🎯 Motivation & Research Challenge
Mathematical reasoning in small language models (270M parameters) presents unique challenges: limited capacity for complex reasoning, tendency for verbose explanations, and difficulty in learning structured problem-solving approaches. The goal was to implement Group Relative Policy Optimization (GRPO) from scratch to enhance chain-of-thought reasoning while maintaining computational efficiency.
🔧 GRPO Implementation from Scratch
Algorithm Innovation
- Group Relative Optimization: Custom implementation using TRL 0.21.0 framework
- Policy Architecture: Gemma-3-270M with specialized mathematical reasoning head
- Reference Model: Frozen SFT checkpoint for KL divergence regularization
- Reward Engineering: Multi-component reward function with efficiency penalties
Training Infrastructure
- Memory Optimization: 15GB VRAM constraint (down from 25GB+ baseline)
- Precision: BF16 mixed precision for 2x memory reduction
- Batch Strategy: Gradient accumulation (4-8 steps) + dynamic batching
- Distributed Setup: Multi-GPU training with gradient synchronization
⚡ Advanced Reward Engineering
Custom Reward Function Design
R = Correctness + Efficiency + KL Regularization
- Correctness Component:
- SymPy-based mathematical equivalence checking (handles algebraic simplification)
- Numerical tolerance for floating-point comparisons (±1e-6)
- Multi-format answer parsing (fractions, decimals, expressions)
- Binary reward: +1.0 for correct, 0.0 for incorrect
- Efficiency Penalty:
- Token count penalty: -λ × (tokens in <think>...</think>)
- Encourages concise reasoning while maintaining accuracy
- Hyperparameter λ = 0.01 (tuned empirically)
- KL Regularization:
- Prevents policy drift from SFT reference model
- β = 0.02 (KL coefficient) for stable training
- Computed per-token for fine-grained control
🔬 Memory & Compute Optimizations
Memory Engineering
- Gradient Accumulation: 4-8 steps to simulate larger batch sizes
- Activation Checkpointing: Trade compute for memory (30% reduction)
- Dynamic Padding: Variable sequence lengths to minimize waste
- Model Sharding: Distribute model weights across GPUs
Training Optimizations
- Learning Rate Schedule: Cosine annealing with warmup
- Attention Implementation: "eager" mode for compatibility
- Checkpoint Strategy: Save every N steps, keep last 3
- Monitoring: Real-time reward tracking and KL divergence
📊 Training Results & Analysis
Achieved Performance Metrics
- Training Steps: ~1200 GRPO iterations with stable convergence
- Memory Usage: Reduced from 25GB+ to 15GB VRAM (40% improvement)
- Reward Convergence: Steady improvement in mathematical accuracy
- Efficiency Gains: 25% reduction in reasoning verbosity while maintaining correctness
- KL Stability: Maintained <0.1 KL divergence from reference model
🔬 Technical Innovations
- GRPO from Scratch: Complete implementation of group relative policy optimization algorithm
- Mathematical Reward Design: Novel approach combining correctness, efficiency, and stability
- Memory-Efficient Training: Techniques for training large models on constrained hardware
- Structured Reasoning: <think>...</think> format for interpretable mathematical reasoning
🏭 2023-Present: Production RAG System (ARGO DATA)
Signal: Production Scale / Latency Engineering / System Design
🎯 Motivation & Production Challenge
Building a production RAG system that serves `200+` concurrent users with sub-100ms latency requires solving complex challenges: real-time index updates, content change detection, embedding consistency, and fault tolerance. The system needed to be "self-healing" - automatically adapting to content changes without manual intervention.
🔧 Self-Healing Architecture Design
Change Detection Pipeline
- File System Watchers: Real-time monitoring of wiki content directories
- Content Hash Tracking: SHA-256 hashing for detecting granular changes
- Semantic Diff Analysis: NLP-based change significance scoring
- Batch Processing: Intelligent grouping of related changes
Intelligent Re-indexing
- Incremental Updates: Only re-process changed content sections
- Dependency Tracking: Update related documents automatically
- Zero-Downtime Deployment: Blue-green indexing strategy
- Rollback Capability: Automatic reversion on quality degradation
⚡ Production-Scale Optimizations
- Embedding Pipeline Optimization:
- Batch Processing: Process 100+ documents simultaneously
- GPU Acceleration: CUDA-optimized embedding generation
- Caching Strategy: Redis-based embedding cache with TTL
- Async Processing: Non-blocking embedding updates
- Vector Database Engineering:
- Pinecone Optimization: Custom indexing strategy for 1M+ vectors
- Sharding Strategy: Namespace-based data partitioning
- Query Optimization: Metadata filtering for faster retrieval
- Connection Pooling: Persistent connections for reduced latency
🔬 Latency Engineering Deep Dive
Sub-100ms P50 Latency Breakdown
- Query Embedding: <10ms (cached model inference)
- Vector Search: <30ms (Pinecone optimized queries)
- Context Assembly: <15ms (parallel document retrieval)
- LLM Generation: <40ms (streaming response initiation)
- Total P50: 95ms average response time
🏗️ Infrastructure & Reliability
FastAPI Backend
- Async Architecture: Handles 200+ concurrent connections
- Connection Pooling: Persistent database connections
- Rate Limiting: Per-user and global rate limits
- Health Checks: Continuous system monitoring
Monitoring & Observability
- Prometheus Metrics: Custom metrics for RAG performance
- Grafana Dashboards: Real-time system visualization
- Alert System: Automated incident response
- Performance Tracking: Query latency and accuracy metrics
📊 Production Performance Metrics
Achieved Scale & Performance
- Concurrent Users: 200+ simultaneous active sessions
- Response Latency: 95ms P50, 150ms P95
- Throughput: 1000+ queries per minute sustained
- Uptime: 99.7% availability (production SLA)
- Index Updates: Real-time processing of content changes
- Memory Efficiency: 8GB RAM for full system operation
🔬 Technical Innovations
- Self-Healing Index: Automatic content change detection and re-indexing
- Latency Optimization: Multi-level caching and async processing
- Production Reliability: Circuit breakers, health checks, and auto-recovery
- Scalable Architecture: Horizontal scaling with load balancing
👁️ 2023-Present: ID Verification Vision System (ARGO DATA)
Signal: Computer Vision / Cloud Cost Optimization / Production ML
Challenges Solved
Cut vendor API costs by ~60% by replacing 3rd-party APIs with in-house PyTorch models deployed on Azure.
Technical Depth
- Architecture: "Hydra-Net" architecture (3 heads, 1 backbone) for multi-task learning
- Optimization: 50% memory usage reduction enabling efficient autoscaling
- Cost Engineering: Significant cost reduction while maintaining accuracy
- Cloud Deployment: Azure-based inference with auto-scaling capabilities
- Model Design: Multi-head architecture for document verification tasks
🛰️ 2022: Hyperspectral Super-Resolution (ISRO Research)
Signal: HPC / CUDA Optimization / Research Rigor
Challenges Solved
Accelerated training 30x on 1TB+ satellite datasets via custom CUDA-level optimizations for hyperspectral image processing.
Technical Depth
- Performance: 30x training acceleration through CUDA optimization
- Scale: Handling 1TB+ satellite datasets efficiently
- Architecture: SR-GAN pipeline for 4x resolution upscaling (20m → 5m)
- Infrastructure: Multi-GPU cluster optimization and distributed training
- Research Impact: Published research with ISRO collaboration
🚦 2022: TrafficSwarm (Multi-Agent Reinforcement Learning)
Signal: Reinforcement Learning / Multi-Agent Systems / Distributed AI
Challenges Solved
Solved decentralized coordination for traffic grid optimization using shared-context reinforcement learning.
Technical Depth
- Multi-Agent RL: Coordinated behavior across multiple autonomous agents
- Algorithm Development: Custom policy optimization algorithms using RLlib and PyTorch
- Distributed Systems: Decentralized coordination without central control
- Simulation: Complex traffic simulation environments with realistic constraints
- Performance: Improved traffic flow efficiency through learned coordination
🔬 Research & Innovation Highlights
Core ML/DL Expertise
- Foundation Models: RLHF, post-training optimization, and fine-tuning at scale
- Computer Vision: Multi-task learning, super-resolution, document processing
- Reinforcement Learning: Policy optimization, multi-agent systems, reward engineering
- Production ML: Latency optimization, cost engineering, scalable deployment
Technical Specializations
- Optimization: CUDA programming, memory optimization, distributed training
- Architecture Design: Multi-head networks, attention mechanisms, efficient inference
- MLOps: Production deployment, monitoring, auto-scaling, cost optimization
- Research: Academic collaboration, publication-quality research, novel algorithm development
Technology Stack
- Frameworks: PyTorch, Transformers, RLlib, LangChain
- Infrastructure: Azure ML, CUDA, Multi-GPU clusters, Docker
- Databases: Pinecone, Vector databases, Real-time indexing
- APIs: FastAPI, Production serving, Auto-scaling systems
📊 Impact Metrics
- Production Scale: `200+` concurrent users with sub-100ms latency
- Cost Optimization: 60% reduction in vendor API costs
- Performance: 30x training acceleration through optimization
- Research: Published work with government research organization (ISRO)
- Open Source: Multiple repositories with community adoption
This portfolio demonstrates deep expertise across the full ML/DL lifecycle, from research and algorithm development to production deployment and optimization.