Ranjan Kumar
AI & ML Engineer · Author · Educator
I help AI builders design, build, and ship production-grade AI systems that actually work, cost-effectively, through hands-on writing, books, and practical engineering guidance.
Latest Posts
View all →What Three Audits Found in My Own LangGraph Book
The factual claims held. What broke was scope - and the audit that caught the book's scope error made one of its own.
ai_mlChat Templates: The Last Unowned Layer in Your LLM Stack
Hugging Face named it the Silent Performance Killer in 2023. By 2026 the word silent was gone from the docs, and when they built the return path they chose JSON over Jinja.
ai-engineeringSuperpowers Plugin for Claude Code: Install and Verify
Install it, prove which skills actually fire, and measure what it costs you - then switch it off where it does not belong.
ai-engineeringBM25 vs Dense Retrieval: Measure It on Your Own Corpus
Build a bake-off harness that runs BM25, dense, hybrid, and reranked retrieval over a labelled query set - and tells you with Recall@k, nDCG, and cost per query which one your RAG system actually needs.
My Books
The ChatML (Chat Markup Language) Handbook
A Developer’s Guide to Structured Prompting and LLM Conversations
Learn how to structure prompts using ChatML for predictable, production-ready LLM behavior.
Building Real-World Agentic AI Systems with LangGraph
Designing, building, evaluating, and shipping stateful, durable, multi-agent systems on LangGraph 1.x
A practitioner's guide to designing, deploying, and operating reliable agentic AI systems in the real world.
The Chat Templates Handbook
A Developer’s Guide to Jinja, apply_chat_template, and Rendering Model-Ready Prompts
A curated collection of battle-tested templates for common LLM tasks and workflows.
My Toolkit
A collection of tools I've built to boost productivity and simplify workflows.
Developer & AI Tools
Test Your Knowledge
Quiz yourself on AI engineering, observability, and production LLM systems
MedhaV - मेधावी
Start every day with clarity
Imagelly
AI-Based SaaS Image Edit/Enhancement Tool
Mermaid Diagram Generator
Create flowcharts, sequence diagrams, and more
MermAniSt — Mermaid Animation Studio
Turn Mermaid diagrams into animated presentations
LinkedIn Text Formatter
Format your LinkedIn posts with bold, italic, and more
MarkMelon: Markdown Editor
Edit, generate docs from Markdown and more
Slides Creator from Markdown
Generate beautiful presentations from Markdown
What I Write About
AI & ML Engineering
Production-ready AI systems, LLMs, and machine learning deployment strategies.
System Design
Scalable architectures, distributed systems, and infrastructure for AI applications.
Real-World Projects
Case studies, lessons learned, and practical insights from production deployments.
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