Andrej Karpathy-Style Comprehensive Transformers from Scratch for Research Foundations

Master the Transformer architecture from first principles, building a deep, intuitive understanding for advanced research and application in modern AI.

The Sequence Problem: Why Traditional Models Struggle

Unit 1: Understanding Sequences

Unit 2: Traditional ML's Limitations

Unit 3: The Need for New Models

Recurrent Neural Networks (RNNs): A First Attempt at Sequences

Unit 1: Introducing Recurrent Neural Networks

Unit 2: The Core Mechanics of Simple RNNs

Unit 3: RNN Architectures and Applications

Unit 4: Training and Limitations of Simple RNNs

Unit 5: Conceptual Implementation of Simple RNNs

The Achilles' Heel of RNNs: Vanishing/Exploding Gradients

Unit 1: Understanding Gradient Flow in Neural Networks

Unit 2: The Vanishing Gradient Problem in RNNs

Unit 3: The Exploding Gradient Problem in RNNs

Unit 4: RNN Limitations and the Need for Alternatives

Convolutional Neural Networks (CNNs) for Sequences: Local Views

Unit 1: CNNs: A Quick Primer

Unit 2: CNNs for Sequences: 1D Convolutions

Unit 3: Limitations of CNNs for Sequences

The Parallelization Imperative: Why We Need a New Paradigm

Unit 1: The Need for Speed: Why RNNs Are Slow

Unit 2: Beyond RNNs: Seeking Parallel Solutions

Unit 3: Setting the Stage for Transformers

Attention: The Core Idea of 'Paying Attention'

Unit 1: Beyond Fixed Contexts

Query, Key, Value: The Building Blocks of Attention

Unit 1: Understanding the Core Components of Attention

Unit 2: Q, K, V in Action: From Words to Vectors

Unit 3: The Interplay of Q, K, and V

Dot-Product Attention: The Raw Score Calculation

Unit 1: The Essence of Dot Product Attention

Unit 2: Matrix Multiplication for Efficiency

Unit 3: Conceptualizing the Raw Scores

Scaled Dot-Product Attention: Stabilizing the Scores

Unit 1: The Need for Scaling Attention Scores

Unit 2: The Scaling Solution

Softmax and Weighted Sum: Turning Scores into Probabilities and Outputs

Unit 1: From Raw Scores to Meaningful Weights

Unit 2: The Weighted Sum: Combining Information

Self-Attention: Attending to Oneself

Unit 1: Understanding Self-Attention

Unit 2: Deep Dive into Self-Attention Mechanics

Unit 3: Self-Attention in Context

Implementing Scaled Dot-Product Self-Attention from Scratch (Conceptual)

Unit 1: Setting the Stage for Self-Attention

Unit 2: Calculating Attention Scores

Unit 3: Producing the Attention Output

Multi-Head Attention: Diverse Perspectives

Unit 1: Beyond a Single Focus

Unit 2: The Multi-Head Mechanism

Unit 3: Finalizing Multi-Head Output

Implementing Multi-Head Attention from Scratch (Conceptual)

Unit 1: Setting the Stage for Multi-Head Attention

Unit 2: Independent Projections for Each Head

Unit 3: Parallel Attention Computations

Unit 4: Combining Head Outputs

Unit 5: Putting It All Together

Positional Encoding: Injecting Order into Orderless Attention

Unit 1: The Need for Position

Unit 2: Types of Positional Encodings

Unit 3: Sinusoidal Positional Encoding

Unit 4: Learned Positional Embeddings

Unit 5: Integrating Positional Encoding

Sinusoidal Positional Encoding: A Deterministic Approach

Unit 1: The Need for Position

Unit 2: Introducing Sinusoidal Encoding

Unit 3: Properties and Advantages

Unit 4: Integration and Alternatives

Unit 5: Practical Considerations

Learned Positional Embeddings: An Alternative Strategy

Unit 1: Understanding Learned Positional Embeddings

Unit 2: Practical Considerations and Comparisons

Unit 3: Refining Positional Understanding

Feed-Forward Networks (FFN): Per-Position Transformations

Unit 1: Understanding the FFN in Transformers

Unit 2: FFN Architecture and Operation

Unit 3: FFN in the Transformer Block

Unit 4: Practical Aspects and Alternatives

Unit 5: Review and Consolidation

Layer Normalization: Stabilizing Activations

Unit 1: The Need for Normalization

Unit 2: Layer Normalization Explained

Unit 3: Layer Normalization in Transformers

Unit 4: Practical Considerations and Alternatives

Unit 5: Review and Application

Residual Connections: Enabling Deeper Networks

Unit 1: The Problem with Deep Networks

Unit 2: Introducing Residual Connections

Unit 3: Benefits and Impact

The Encoder Block: Assembling the First Half

Unit 1: The Encoder Block: Putting It All Together

Unit 2: The Encoder Block: The Second Half

Unit 3: Encoder Block: Forward Pass and Implementation

Causal (Masked) Self-Attention: Preventing Future Peeking

Unit 1: Understanding Causal Attention

Unit 2: Implementing Causal Masking

Unit 3: Causal Attention in Practice

Unit 4: Advanced Masking Concepts

Unit 5: Impact and Implications

Encoder-Decoder Attention (Cross-Attention): Bridging Source and Target

Unit 1: Understanding Cross-Attention's Role

Unit 2: Mechanics of Cross-Attention

Unit 3: Cross-Attention in Context

The Decoder Block: Generating Sequences

Unit 1: Decoder Block Essentials

Unit 2: Decoder Block Architecture

The Full Transformer Architecture: Encoder-Decoder for Sequence-to-Sequence

Unit 1: Putting It All Together: The Encoder-Decoder Journey

Unit 2: The Encoder Stack: Deepening Understanding

Unit 3: The Decoder Stack: Generating with Context

Unit 4: Output and Training

Computational Complexity and Memory Footprint of Attention

Unit 1: Understanding Computational Cost

Unit 2: Attention's Computational Demands

Unit 3: Memory and Scaling Challenges

Transformer Variants: BERT (Encoder-Only) and GPT (Decoder-Only)

Unit 1: Why Variants? Tailoring Transformers

Unit 2: BERT: The Encoder-Only Powerhouse

Unit 3: GPT: The Decoder-Only Generator

Unit 4: Comparing BERT and GPT