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 →LangGraph create_agent: The Graph Isn't the Runtime
Bind three tools or three hundred - the rendered diagram is byte-identical. The constraints that actually decide the next step live in middleware nobody draws.
ai-engineeringLangGraph or a While Loop? You Already Have a Runtime
A checkpointer makes the run's past readable and leaves its next-step space exactly as wide as it was. Production agents fail in that gap.
ai-engineeringLangGraph Reducers Are a Concurrency Policy
Rename a node and the answer changes. The code that decides how concurrent writes merge lives inside a type annotation, appears on no diagram, and the docs decline to guarantee its order.
ai-engineeringAgentOps: A Band Is a Comment Until Something Enforces It
Six articles said enforce the boundary outside the agent. This is what the outside is made of - and almost nobody has built it.
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.