
Developing LLM Applications Using RAG (feat. LangChain)
jasonkang
RAG. Learn from Silicon Valley GenAI Hackathon Winner. Packed with real-world know-how.
Basic
LLM, RAG, LangChain
LangGraph, packed with the know-how of an AI Agent lead from a major corporation. I will pass on the knowledge I've gained through trial and error in the field.
2,588 learners
Level Basic
Course period Unlimited
Reviews from Early Learners
5.0
ChangHwan Jang
[Course Structure] - It was great that rather than being textbook-like, it felt like you were passing on know-how for issue resolution experienced in actual work - Although I haven't developed LLM Applications yet, the course was thoroughly reviewed enough that ideas came to mind immediately after watching the lectures - Considering that you can't get everything from one course, following Byungjin's roadmap will eventually build confidence in LLM Application development through the course structure [Teaching Method] - There may be personal preferences, but the explanations really sink in and are understandable, giving you confidence that you can follow along - Even for items that could be easily overlooked, detailed examples helped understand both code and architecture at once - Most importantly, the instructor's pride in working in this field and teaching classes in this area has the effect of boosting students' confidence as well [Overall Assessment] - Using generative AI alone is insufficient, and to strengthen security against internal information being uploaded to external clouds, it's determined that LLM Applications must be developed in-house. I'm confident that completing all the courses in this roadmap will reach a certain level. ^^ - I think I will definitely take any courses that are continuously released. - It would be great if you could also provide offline sessions in addition to Online Classes. Keep fighting! ^^
5.0
johnsonmoshy6
실습 위주의 훌륭한 강의입니다! LangGraph, MCP, RAG 같은 복잡한 내용을 쉽게 설명해 주셔서 이해하기 쉬웠고, 실무에 바로 적용할 수 있었습니다. 강사님의 설명이 정말 명확하고 유익했어요. 추천드립니다!
5.0
JAY probio
Finished the course in just two days, and even got an MCP update!!! Honestly, the tuition fee is too cheap. I wish you'd raise the price so others wouldn't find out, but to help the instructor create more great lectures, there needs to be more students 😊😊 This is a core lecture that picks out only the essential points. If you want to utilize LLM 200%, make sure to take this course, and take it twice.
LLM Agent
LLM
Prompt Engineering
Retrieval Augmented Generation(RAG)
AI Agent
LLM agents play a key role in understanding user needs, automating complex tasks, and solving problems. However, the process of designing and implementing agents is not easy due to structural complexity and frequent repetitive tasks. LangGraph simplifies this process, helping you efficiently develop powerful LLM agents.
✅ Only the core essentials from the vast official documentation!
The LangGraph official documentation is extensive, but the necessary information is limited. We have prepared a curriculum focused on key concepts personally selected based on the experience of field engineers.
✅ Exactly the way it's used in the industry!
We show the entire process of prompt writing and debugging without any editing. Through this course, you can experience how actual engineers resolve errors and optimize prompts.
Developers with LangChain experience
If you have experienced the limitations of LangChain, this course will give wings to your agent development.
Developers curious about LLM Agents
An industry expert will teach you about Agentic AI, which was mentioned by NVIDIA's Jensen Huang at CES 2025.
Tech entrepreneurs and startup teams
If you are looking to develop AI-based products or services, you can learn the latest technologies in agent development.
Understand the differences between LangGraph and LangChain: By identifying the structural differences and usage patterns of the two frameworks, you can select the most suitable tool for your project.
Agent Design and Implementation: You can design various agents such as Retrieval agents, Self-RAG, and Corrective RAG, and automate workflows.
Complex Workflow Construction: You can design workflows that efficiently handle complex tasks using Multi-Agent systems and RouteLLM.
Tool Utilization Skills: You can expand an agent's functionality and improve problem-solving capabilities by utilizing various tools within LangGraph.
Even if they perform the same function, prompts must be written differently depending on the model used. You will learn how to efficiently write prompts tailored to each situation using LangGraph's PromptTemplate and ChatPromptTemplate.
Instead of using expensive high-end models like gpt-4o, it is more efficient to break tasks into smaller units and repeatedly utilize lightweight models such as gpt-4o-mini. You will learn how to optimize cost and performance by dividing prompts into smaller segments. sẽ hiệu quả hơn. Bạn sẽ được học cách tối ưu hóa chi phí và hiệu suất bằng cách chia nhỏ các câu lệnh (prompt) thành các đơn vị nhỏ hơn.
You will learn not only how to use the basic tools of LangChain but also how to expand functionality by developing custom tools for agents to use as needed. Additionally, you can implement more reliable agents by designing human-in-the-loop systems where humans intervene in the process.
(Former) Development and operation of GS Group GenAI Platform
(Former) Tech Lead at a Series C medical AI startup
(Former) Hanghae Plus AI Course Coach
I have included the know-how gained from coaching the GS Group Hackathon and developing/operating various real-world projects..
Q. What is the difference between LangChain and LangGraph?
While LangChain primarily connects tasks in a chain format, LangGraph allows for the construction of more complex workflows using a graph structure. LangGraph supports various agent tasks through flexible node connections.
Q. I am new to LangChain; can I still take the course?
If you have experience using Python, you should have no problem taking the course, but if you are not familiar with LangChain syntax, you may find it difficult to understand.
If you are new to LangChain, I recommend the instructor's beginner course.
Q. What should I do if there is something I don't understand during the course?
If you have any questions during the course, please feel free to post them in the Inflearn Q&A section! I will respond as quickly as possible and
update the lecture with additional recordings if necessary.
Operating System and Version (OS): MacOS
As long as you have an environment where Python can run, you can follow the course regardless of your operating system, such as Windows or Linux.
Tools used:
All live coding will be conducted in a Notebook environment.
There is no specific editor recommended, but Cursor is used in the lectures.
The source code for the Notebooks used in the lecture is provided as a GitHub Repository
It includes supplementary explanations through "comments" and "Markdown" that are not present in the lecture videos.
A Notion page for theoretical explanations is provided.
Prerequisite Knowledge: Python
Optional knowledge: LangChain
This course is an intermediate-level lecture targeted at those with experience using LangChain.
You may be able to understand the course even without prior experience with LangChain, but if you have no experience at all, you might find it difficult to follow along.
If you would like to study LangChain first, I recommend the instructor's other courses.
Who is this course right for?
Developers interested in LLM
Developers who are deploying or operating LLM applications
Developers who want to enhance their LLM applications
Need to know before starting?
Python
Inflearn Verified
Career Verified
19,264
Learners
1,548
Reviews
533
Answers
4.9
Rating
10
Courses
FAANG Senior Software Engineer
(Former) GS Group AI Agent platform development/operations
(Former) GS Group DX BootCamp Mentor/Coach
(Former) FAANG Senior Software Engineer (Former) GS Group AI Agent Platform Development/Operations (Former) GS Group DX BootCamp Mentor/Coach
(Former) Tech Lead at a Series C AI Startup
Stanford University Code in Place Python Instructor
Naver Boostcamp Web/Mobile Mentor
Naver Cloud YouTube Channel presenter
Author of Building Autonomous AI Agents with LangChain & LangGraph

Wanted Pre-onboarding Frontend/Backend Challenge Instructor (6,000+ cumulative participants)
Hanghae AI Plus Course 1st Generation Coach
All
29 lectures ∙ (6hr 20min)
Course Materials:
All
234 reviews
4.9
234 reviews
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Edited
5
I received so much help from the Langchain basics to the RAG lectures, so I also took the LangGraph course. They explain the content that can be used directly in the field with high quality and in a very detailed manner. You mentioned in the lecture that you have plans to publish a book, and I would appreciate it if you could mention it in a community or something when it is published. I am interested in purchasing it.
Wow, that's a really touching review! 🥹🙏 I prepared my lecture so that it can be applied directly to practical work, so I feel very rewarded to receive such good feedback. Thank you so much for being with me from LangChain to LangGraph! I'm also working hard to prepare for the publication of the book, and I'll be sure to let you know in the community! The fact that you are interested in this gives me great strength. I will continue to repay you with helpful lectures and content. Thank you again for leaving such a sincere review!
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5
실습 위주의 훌륭한 강의입니다! LangGraph, MCP, RAG 같은 복잡한 내용을 쉽게 설명해 주셔서 이해하기 쉬웠고, 실무에 바로 적용할 수 있었습니다. 강사님의 설명이 정말 명확하고 유익했어요. 추천드립니다!
친절한 말씀 정말 감사합니다! 강의가 도움이 되었다니 기쁘네요. 저는 직장에서 다른 엔지니어들에게 LangGraph를 사용하고 실제 프로젝트에서 AI 에이전트를 구축하는 방법을 가르치고 있는데, 그런 실무 경험이 자연스럽게 이 강의에도 반영된 것 같습니다. 그런 실무 배경이 개념을 더 접근하기 쉽고 적용 가능하게 만드는 데 도움이 되었다니 정말 좋네요.
Reviews 4
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Average Rating 5.0
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