Series

Multi-part deep dives — each series builds one thing end to end, with experiments you can rerun yourself.

Kv Measured

1 part

Every list of KV cache techniques presents a dozen of them as peers. On one A100 the spread is enormous: prefix reuse cut a shared-prefix workload from 59.4s to 6.2s, while tuning the paged block size moved capacity by under 1%. The reason you cannot rank them on one number is that they pay out in different units.

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Paper of the Week

3 parts

I trained BDH and counted more than 4.8 billion activations across three controls. Training moved its single-latent sparsity from 49.98% to 81.65%, but a similar-budget ReLU baseline reached 91.04%. Sparsity is real; by itself, it is not evidence of interpretability.

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Moe K2 Experts

2 parts

We reproduced Table 5 of arXiv:2609.04575 on one A100 and measured the throughput the paper leaves out: nothing in HF transformers, nothing at batch 1 in stock vLLM, 1.35× at batch 8.

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TurboQuant

6 parts

Compress KV cache to 3-bit with PolarQuant + Lloyd-Max. 4.6x memory savings with zero accuracy loss, no retraining.

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Hybrid Mamba Transformer

2 parts

NVIDIA Nemotron 3 Nano, Qwen 3.5, and Mamba-3 independently converge on 75% linear layers + 25% attention + MoE. 88% KV-cache reduction, O(n) complexity for long-context processing.

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How AI Works

2 parts

We measure, on a local model and on GPT-4o-mini, exactly how much answers change with sampling temperature. Temperature doesn't create diversity -- it amplifies what's already there.

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Claude Watermark

2 parts

Every piece of text Claude generates now carries an invisible watermark — with nothing added to the text. A step-by-step walkthrough of SynthID-Text: the secret key, tournament sampling, detection, and the honest limits.

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AI Memory Mastery

3 parts

karpathy-skills, claude-mem, Cognee — comparing 3 approaches to solving the AI memory problem.

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LLM Inference

4 parts

Build Self-Attention from scratch. Compare MHA → GQA → MQA evolution in code. KV Cache mechanics and Prefill vs Decode analysis.

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Lora Finetuning

4 parts

From LoRA theory to Qwen 2.5 7B model setup. 99.8% parameter reduction and 86% memory savings vs full fine-tuning, explained with code.

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AgentScope

6 parts

Install AgentScope, learn 5 core concepts (Agent, Model, Memory, Toolkit, Formatter), and build a tool-using ReAct agent.

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AutoResearch

4 parts

A code-level deep dive into Karpathy's autoresearch. Dissecting train.py, BPE tokenizer, MuonAdamW optimizer, and the agent protocol design.

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DeerFlow Multi Agent

4 parts

DeerFlow 2.0 architecture, setup, and first task execution. A SuperAgent runtime with 9 agent nodes, 5 tool sources, and Docker sandboxes.

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Qwen3.5 Vs DeepSeek V3.2

3 parts

Complete comparison of Qwen 3.5 and DeepSeek V3.2: architecture, benchmarks, hardware requirements, and practical recommendations.

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Agentic RAG

3 parts

Diagnose naive RAG limitations, classify query intent, and route to the optimal retrieval source with LangGraph. Implement adaptive retrieval that skips unnecessary searches.

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LLM Agent

4 parts

Understand the foundational ReAct pattern. The difference between chatbots and agents, the Thought-Action-Observation loop, and why ReAct falls short in production.

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Backprop From Scratch

1 part

How microgpt.py's 15-line backward() works. From high school calculus to chain rule, computation graphs, topological sort, and backpropagation.

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microGPT

1 part

A line-by-line dissection of microgpt.py -- a pure Python GPT implementation with zero dependencies. Training, inference, and autograd in 150 lines.

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Diffusion LLM

2 parts

D3PM, Transition Matrices, Absorbing States, MDLM -- how to bring diffusion from continuous space to discrete tokens.

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LLM Reasoning Failures

3 parts

Reversal Curse, Counting, Compositional Reasoning — fundamental Transformer failures tested across 7 models.

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Logit Lens To Tuned Lens

1 part

Individual neurons are uninterpretable. Sparse Autoencoders extract monosemantic features from model internals, and TensorLens analyzes the entire Transformer as a single unified tensor.

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Demo To Prod Part1

3 parts

5 Non-Negotiable Standards for Enterprise Deployment

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Advanced RAG

8 parts

Why can't traditional RAG answer "What are the main themes in these documents?" Microsoft Research's GraphRAG reveals the secret of community-based search.

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Ontology Knowledge Graph RAG

1 part

Vector search alone isn't enough. Upgrade your RAG system with Knowledge Graphs that understand entity relationships.

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Claude Code Context

3 parts

What if Claude automatically ran lint, tests, and security scans every time it generated code? Learn how to automate team workflows with Hooks.

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Claude Code MCP

1 part

What if Claude could read Jira tickets, send Slack messages, and query your database? Learn how to extend Claude's capabilities with MCP servers.

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SQL Analytics

12 parts

EXPLAIN, indexes, WHERE vs HAVING — diagnose and optimize slow queries yourself

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DDPM Diffusion Models

6 parts

U-Net shows diminishing returns when scaled up. DiT improves consistently with size. Complete analysis of the architecture behind Sora.

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