Series

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

All series

SOTAAZ Series

SQL Analytics

12 parts

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

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SOTAAZ Series · image diffusion

Diffusion Models, DDPM to SANA

8 parts

Derives DDPM's forward process from the beta schedule, the closed form that jumps straight to any timestep, the reverse process and its posterior, the ELBO, and the reparameterization to noise prediction. Every equation worked through rather than quoted.

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SOTAAZ Series · LLM quantization and KV cache

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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SOTAAZ Series · GraphRAG

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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SOTAAZ Series

Paper of the Week

7 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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SOTAAZ Series · diffusion LLMs

Diffusion LLM

5 parts

From DDPM to LLaDA 2.1 -- everything about diffusion-based LLMs. Masked Diffusion, Token Editing, and MoE scaling dissected across 4 parts.

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SOTAAZ Series

AI Memory Mastery

3 parts

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

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SOTAAZ Series · AI agents

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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SOTAAZ Series · AI agents

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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SOTAAZ Series

GPT-2 to the Speedrun, Measured

5 parts

A condensed walk through the 4-hour video: building GPT-2 (124M), taking a step from 1,000 ms to 90 ms on one A100, the GPT-3 training settings, and a 10B-token run that beat OpenAI's checkpoint on HellaSwag. Plus one check we ran: nanoGPT's exact GELU moves logits by up to 5 against GPT-2's.

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SOTAAZ Series · LLM quantization and KV cache

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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SOTAAZ Series · AI agents

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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SOTAAZ Series · RAG and evaluation

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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SOTAAZ Series · AI agents

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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SOTAAZ Series

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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SOTAAZ Series · LLM quantization and KV cache

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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SOTAAZ Series

LLM Reasoning Failures

4 parts

Stanford researchers analyzed 500+ papers to systematically map LLM reasoning failures. From cognitive biases to the reversal curse, discover where and why AI reasoning breaks down.

Start with the intro →
SOTAAZ Series

Claude Code in Practice

5 parts

One CLAUDE.md file can dramatically change your AI coding assistant's performance. Learn how to keep Claude on track in large-scale projects.

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SOTAAZ Series · interpretability

Logit Lens to Tuned Lens

2 parts

What happens inside an LLM between input and output? Logit Lens and Tuned Lens let us observe how Transformers build predictions layer by layer.

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SOTAAZ Series

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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SOTAAZ Series

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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SOTAAZ Series · LLM quantization and KV cache

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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SOTAAZ Series · RAG and evaluation

Demo to Production

4 parts

Common patterns across AI, RAG, and ML projects — why does "it worked fine" fall apart in production?

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