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Backend 6-Week Practical Mission and 1:1 Feedback to Complete a Winning Portfolio - 2nd Cohort

This is a 6-week challenge program that transforms your projects into competitive portfolios you can showcase on your resume through weekly hands-on missions. Rather than simple assignment submissions, industry professionals directly review your work and provide immediately applicable improvement suggestions. You can even prepare in advance for "What kind of questions might come up in interviews with this level of work?"

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Java
Spring
MySQL
Redis
Resume

77개 수업 학습

5회 미션 수행

무제한 복습, 내 것으로 만들어요.

같은 기수와 교류하고 함께 성장해요.

질문하고 즉시 답을 얻어요.

dingcodingco님과 함께해요!

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Career Verified

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Learners

1,811

Reviews

346

Answers

4.9

Rating

21

Courses

🚀 Ex-Toss, POSTECH graduate | Current Backend Developer (+8 years)
🎥 YouTuber with 20,000 subscribers | Development content creator
📚 Inflearn Instructor | Cumulative 15,000+ students
👥 Running a developer career community (8,000+ members)
🧩 Contributor to various open source projects (Gradle, Spring AI, etc.)
📝 Passed 38 resume screenings and conducted 100+ resume reviews on Kmong (5.0 rating)

I deliver vivid, real-world industry insights in an easy-to-understand and deductive manner.

Inflearn Interview Link!

More

Java, Spring, MySQL....

I've learned all of this, so why do my resumes keep getting rejected?

As a backend developer, I couldn't include core technologies like DB indexing, transactions, server optimization, and Redis in my resume
because I lacked problem-solving experience with them.


So then, can you confidently answer the questions below?

DB Indexing: How did you shorten slow queries, and can you show the results with numbers?

Transaction: How did you resolve concurrency issues or bottleneck problems?

Server Optimization: What is the specific process for achieving high performance with minimal resources?

Redis: Do you have experience dramatically improving processing speed by utilizing cache?


If you cannot provide clear answers to these four questions,

In just 6 weeks through lectures, build real problem-solving experience and
learn how to properly incorporate that process into your resume.


Even before entering the interview room,
only applicants who have sufficiently answered in their resume can pass document screening and succeed in interviews.
Now, become a competitive backend developer who clearly demonstrates "Problem → Solution → Result"!

Real reviews from those who took the course and passed

2025/05/24 Document Screening Passed Mr./Ms. Jung**

2025/07/31 Final acceptance at 3 places, Mr./Ms. O**

Actual students' performance improvement results (September 18, 2025)

✅ You'll learn this content.

Backend concepts understood through real-life examples

  • Meal Kit Docker and Hiring Process Filter Overhead

  • Adult Comics and Librarian Optimizer

  • Optimistic and Pessimistic Locking for Toilet Bowls

  • Analogies and explanations you can't forget once you hear them


Kind lectures for beginners

  • Explain why we need to learn this in the first place

  • Provides example code and test code for all concepts

  • Code automation, CI/CD, and practical deployment flow explained from the basics

  • Textbook materials 946 pages provided

Practical Interview Preparation

  • DB Index B-Tree Structure, Covering Index Comparison

  • Transaction isolation levels, MVCC, event publishing preparation

  • Server Optimization JPA and N+1 Problem Bulk Operation Preparation

  • Redis TTL Strategy, Cache Invalidation Strategy Preparation

Practical configuration that can be immediately applied to your project

  • Not just simple concept learning, but problem-solving case-based

  • Structured based on actual performance issues from real domains


  • Directly applicable to resumes through before/after improvement metrics


178 days of development, 946 pages of materials, total of 12,665 lines of code.

I have analyzed hundreds of successful resumes so far.
Those resumes clearly had common characteristics.
Specifically, they contained concrete experiences of solving problems, and proved the results with numbers.
But the phrase 'quantify it' feels abstract and hard to grasp, doesn't it? I felt the same way.


So I organized it specifically and created it as a course.
I developed it for a total of 178 days, with a 946-page textbook, 32 hours of original footage, and 12,665 lines of code.
I systematically structured the content to save your time and enable the most efficient learning possible.
I created this result as a fully subtitled course video through two rounds of meticulous review.
You can get all of this in just under 20 hours.


This course is not just simple theory. Problem identification → Solution experience → Documentation through metrics - it's structured to help you apply these to your projects and create a truly competitive resume.
We'll transform your resume from a simple introduction into a competitive weapon.

✨ Features of This Course

📌 For Beginners

The first student of this course was a non-CS major bootcamp graduate developer.
Therefore, every concept explained starts with "why do we need to learn this".

  • Docker, AWS, Redis

  • Isolation Level, MVCC, Query Plan, Deadlock, Phantom Read, Gap Lock

  • Transaction Propagation, Thread Pool, Cache Avalanche …

We explain these concepts "so that even first-time learners" can understand
using analogies, practical code, and test code.
Rather than simple terminology definitions, we explain why these technologies emerged to solve problems.

Check out Developer Job RPG


📌 Organizing the "quantified experience" from start to finish as a template

"Quantify your resume!"
You've heard this advice a lot, but most people don't actually know how to implement it.

So in this lecture,

A. Problem Situation → B. Solution Method → C. Improvement Metrics

I created this flow so that it can be learned repeatedly in a template format.

You can learn persuasive sentence structures based on data in this course.

Real resume problem-solving cases explained in the lecture


📌 I structured it so that the question "So what should I do?" doesn't remain unanswered.

Lectures that just throw concepts at you and end there,
lectures where you can't even figure out how they connect to real work…
I hated those kinds of lectures the most.


This course connects concepts → problem situations → practical application.
Rather than simple explanations,
it helps you understand "to the extent that you can explain this to someone else and how".


심지어, 실제 [[STRONG_1]]메이저 기업[[/STRONG_1]](네카라쿠배당토 중 하나)의[[BR]][[STRONG_2]]기술 면접[[/STRONG_2]] 강의에서 나온 질문 [[STRONG_3]]80%를 이 강의 하나로[[/STRONG_3]] 커버가 가능했습니다.[[BR]][[STRONG_4]]실제 기업들이[[/STRONG_4]] 문제 해결 사례를 본다는 것의 증거입니다.


📌 I've taken care of all the minor settings for you

  • Complex AWS Configuration

  • Repetitive code base

  • Deployment Environment Setup


I've already done all the tedious work for you.
Just take the insights with you.

Github Actions CI/CD Automation Setup

Automated AWS Infrastructure Setup


📌 Mission and feedback are all ready

Each week, there will be missions to directly apply to your projects.

This course goes beyond simply learning theoretical concepts,
it's a course designed to develop practical skills by actually applying them to your own projects.

Also, for the missions you submit,
I will personally review the results and provide you with specific feedback.

You can apply the concepts you've learned to real projects and develop practical skills
with this thoroughly prepared curriculum.

You will have not just a lecture that you simply listen to,
but an experience of directly applying, receiving feedback, and growing.


I recommend this for people like this

I've written a backend resume, but I don't know where I'm getting rejected.
✔ Those who have listed their skills but don't feel competitive
✔ Those who don't know the difference between a winning resume and their own resume

I have a portfolio, but I don't know how to structure my sentences.
✔ Those who only write feature-listing sentences like "Implemented login API"
✔ Those who want to incorporate actual problem-solving experience into their resume

I want to prepare for interviews while also improving my resume at the same time.
✔ Those who want to prepare for technical interviews based on their resume content
✔ Those who want to apply transactions, indexes, Redis to
their own projects

🥳🥳🥳 Real Student Reviews 🥳🥳🥳

Developer Job RPG Student Hyeonwoo's Course Review

⛔ ️Caution 1: Taking this course does not guarantee 100% employment

Taking this course doesn't guarantee that you'll definitely pass interviews at top tech companies like Naver, Kakao, Line, Coupang, or Baemin.
The problem-solving examples I've prepared will also be seen by many students over time,
and simply copying these examples may become less effective for differentiation.

So I will not make exaggerated promises like "anyone can definitely pass."

However, there are things you can definitely take away from this course.

Exactly, it's the ability to discover problem situations on your own and organize those solution experiences in a convincing way.
This course is not a passive lecture that only injects specific keywords.
It focuses on the process of creating a resume that proves you are 'a developer who knows how to solve problems'.

Through this course, I hope you will become developers who think independently and continue to grow.


⛔ Note 2: This course does not cover all technologies

This course is not an encyclopedia-style lecture that explains every technology from A to Z.
It focuses on accurately understanding the core concepts needed for problem-solving,
and how to apply them in real domain situations.

For example, it doesn't explain all the features of AWS. It also doesn't cover Docker from start to finish.

However, the core topics of this course:
DB indexes / transactions / server optimization / Redis
are covered in depth sufficient to prepare for interview questions.

In other words, this course is a practical-focused course where you can solve problems encountered in real projects
and incorporate that experience into your resume.
If you need deeper technical exploration, you should expand and study separately afterward.
I will only accompany you to that starting point.


⛔ Warning 3: This course is not cheap.

The cost of this course is not insignificant. I recognize that this price can be quite burdensome for job seekers.
That's why I've put together the content with a sense of responsibility.
I've deliberated extensively on what content is most essential for backend developers at this point in time.
Based on successful resumes and actual questions from technical interviews, I've thought about how to create a compelling resume.

We've reduced the trial and error that could take months when working alone,
allowing you to establish a clear direction with a single investment.

This course is a guide based on 'passing experience' rather than knowledge, and
it's a practical course designed to help you actually revise your resume and prepare for interviews.

I would appreciate it if you think of this not as
'simply listening to lectures' but as
'the cost of properly designing your career.'

I have prepared all the content to meet those expectations.

🎁 EVENT 1 🎁


There are special benefits provided only to those who take the course.

Actually asked at major companies - a collection of technical interview questions.


You can think of this as a special problem book prepared by those who passed the resume screening to prepare for technical interviews.
This problem book will be continuously updated, so you'll be able to prepare for interviews in line with current trends!!

(This problem set is provided as a link in Notion format!)


We'll give this problem book to the first 200 people who write course reviews!

Get it after verifying your course review in the community!

(The authentication method is written in the very last lecture __)


That's not all

Developer Job Preparation Guide (Resume, Portfolio, etc.) included!


🎁 EVENT 2 🎁

After taking the course, the first 10 people who pass the document screening should share their course reviews + document screening success stories in the open chat room!

As a token of appreciation, we are sending you a Starbucks gift card


🎁 EVENT 3 🎁

If you submit the Google form through that link

🎟 We'll provide you with a discount coupon 🎟


🎁 EVENT 4 🎁

Each sincere review provides great motivation and help to other students.

After writing a lecture review on your blog and submitting it through the corresponding link, we'll give you a 30,000 won Coupang Eats gift card!

(However, the completion rate must be 80% or higher)


🎁 EVENT 5 🎁

IntelliJ IDE 3-month free license provided!

We've prepared special benefits through collaboration with JetBrains to support your development studies.
You can use IntelliJ for free for 3 months with the promotion code below!


Promotion Code: HYUNJOONPARKxJB
Benefit Details: JetBrains Single IDE (e.g., IntelliJ, PyCharm, WebStorm, etc.) 3-month free license
Expiration Date: Until May 13, 2026
How to Use😀

1. Access the official JetBrains coupon registration page

2. Select your desired IDE after entering the code

3. Check the license issued via email


Caution:
This code can only be used by new users who are using JetBrains for the first time.
(Only those who have never used a JetBrains paid license before can register)
(You can do this infinitely by creating a new Google email)

2025.05.01 Update

Guide for Docker Image Corruption Cases feat. Anfield


2025.05.05 Update

Why is our db in the public subnet? Section added feat. Hi

2025.05.11 Update

JMH plugin installation instructions added feat. kongminoo


2025.06.02 Update

Added explanation of index data flow feat. Mogging


2025.06.07 Update

Added explanation of criteria for determining driving table and driven table in execution plans feat. cho766


The person who created this course

The behind-the-scenes story of going all the way to final interviews at Coupang and Yanolja - A 6-year developer's job change story across 24 companies [ep 5]

Dingcodingco (Main Instructor)

  • 2021 ~ 2022: S Coding Club Algorithm (data-structure) Tutor

  • 2022 ~ : Operating coding YouTube channel DingCodingCo (featuring various content related to developer job hunting)

  • 2022 ~ 2023 : Viva Republica Server Developer


  • Never give up on students 🦈

  • Developer Job Hunt Mastery Community Management and Offline Meetup Operations


Dungka (Teaching Assistant)

  • NAVER, Kakao, LINE, Coupang, Baedal Minjok, Danggeun Market, Toss developer


Pre-enrollment Reference Information

If!! you have even the slightest hesitation before enrolling in the course.

Am I taking the right course right now?? If you're having doubts, feel free to reach out anytime through our open chat room!!

😍 I'll do my best to answer diligently 😍

Practice Environment

  • I use IntelliJ. The Community (free) version is perfectly fine.

  • Windows, Mac - it doesn't matter! We provide installation methods for all operating systems.


Learning Materials

  • I'll share everything with you via Notion and PDF!

  • I'm sharing the project code with you!

Prerequisites and Important Notes

11월

16일

챌린지 시작일

2025년 11월 16일 오후 03:00

챌린지 종료일

2025년 12월 29일 오후 02:59

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All

82 lectures ∙ (21hr 23min)

Course Materials:

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챌린지에서 배워요

  • Essential Backend Problem-Solving Experience

  • Spring Application Optimization

  • Index and transaction problem situation experience

  • Redis Fundamentals and Problem-Solving Experience

  • Monitoring concepts to actual AWS setup

Recommended for
these people

Who is this course right for?

  • Bootcamp Graduate

  • Spring Backend Developer

Need to know before starting?

  • Backend

  • Spring

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