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 →Contract Tests for a LangGraph Agent: Test the Property, Not the Setting
Build a pytest suite that checks fan-out width, merge order, spend across resumes, and spend after a crash - and watch a setting-shaped fix fail each one.
frontend-architectureFrontend Architecture for GenAI: Why Your React Patterns Don't Work Anymore
> **Updated 2026-09-15** (first published 2026-02-19). The argument and the eight layers still hold, but several things have changed. Libraries now cover the fi...
agentic-aiDesigning User Experience for Agentic AI Systems
> **Updated 2026-09-15** (first published 2026-03-06). The thesis is unchanged, and six months of shipped products and published data now support it. What chang...
ai-engineeringGraph Engineering Draws the Graph. Your Runtime Redraws It.
A recursion limit of 6 let 1,000 research tasks run. Renaming one reviewer node decided whether the run ever ended. A checkpointer handed a spent step budget back at full on every resume.
My Books
The 7 GenAI Architectures
A Field Guide to Choosing the Right AI System — Before You Overbuild It
The seven architectures GenAI systems actually get built on, and how to pick the smallest one that solves your problem.
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.
Get the next article by email
One email when a new piece on production AI engineering goes up — no weekly digest, no drip sequence.