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강의

Course

Instructor
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Challenge
Ended
Programming

/

Back-end

3-Day Complete! NAVER-Kakao-Line-Coupang-Baedal Minjok-Danggeun Market-Toss Backend Interview Survival Challenge

"I have a backend technical interview in a week, what should I start with?" The secret to answers that make interviewers nod Master the actual answer patterns of Naver, Kakao, Coupang, and Toss successful candidates in just 3 days!

Spring
oop
DBMS/RDBMS
cache
index

5개 수업 학습

3회 미션 수행

라이브 3 회

완주 시 쿠폰을 제공해요.

추가 자료를 통해 학습을 이어나가요.

질문하고 즉시 답을 얻어요.

dingcodingco님과 함께해요!

16,528

Learners

1,676

Reviews

308

Answers

4.9

Rating

19

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

해당 강의는 [[STRONG_1]]2025 하반기 서버개발자[[/STRONG_1]] 기술 면접의 [[STRONG_2]]실제 기출문제[[/STRONG_2]]를 착안하여 만들어졌습니다


"I got an interview scheduled, but I don't know what to prepare!!"

"Is it enough to just memorize Java junior backend interview questions?"

That's not right.

Technical interview preparation requires "answer structure".

Same experience, different explanation, completely different results.

Let's prepare together within 3 days.

📍 Day 1: 5 Stages of Decision Flow (Problem→Alternatives→Decision→Implementation→Results)

📍 Day 2: Numbers are the answer (A-B-C formula, Before/After proof method)

📍 Day 3: How to Answer "When You Don't Know" (Customized Strategies for Naver, Kakao, Coupang, Toss)

Live Practice + Immediate Feedback Transform your answers from rejection-worthy to acceptance-worthy in just 3 days.

사내 AI 활용 사례 MVP 선정

📌 Practical Live Challenge

Not just simple lecture viewing, but real-time practice + feedback

3 days of 2 hours daily, practicing answers together with students

The only lecture where I get immediate feedback on my answers

📌 Rejection Cases vs Acceptance Cases Comparative Analysis

Elimination-type answer: "I applied Redis caching"

Winning Answer: "Product inquiry API response time 3 seconds → 0.5 seconds (6x improvement)
TPS 500 → 2000 (4x increase)
DB CPU 80% → 20% (75% reduction)
Verified with Postman and JMeter"

📌 Mastering the Method of Proving with Numbers

Include at least 3 or more specific numerical values in all responses

Before/After comparison, specify measurement tools

Completely remove abstract words like "a lot" and "a little"

Curriculum (3-Day Intensive Course)

📌 Day 1: Speaking with Flow

"I used Redis" → "What problem did you solve, how did you solve it, and how much did it improve?"

  • The 5 Stages of Decision Flow: Problem→Options→Decision→Implementation→Results

  • B-Tree Index Real Reason for Speed (Minimizing Disk I/O)

  • A case where performance became 6 times slower due to a mistake in composite index order

📌 Day 2: Proving with Numbers

"It became much faster" → "6x improvement from 3 seconds to 0.5 seconds"

  • Revealing the Hidden Checklist That Interviewers Use

  • 7 Complete Ways to Master Follow-up Questions (Trade-offs, Alternatives, Failures, etc.)

  • Optimistic Lock vs Pessimistic Lock: Practical Selection Criteria

📌 Day 3: Practical Response by Company

How to respond when you "don't know"

  • 1 minute of silence → immediate elimination. Do this instead

  • Cache Failure 3 Major Patterns: Practical Solutions

  • JPA Bulk Operations 90% Performance Improvement Case Study

Changes After Taking the Course

Before

Interviewer: "Do you have experience using Redis?"

Applicant: "Yes, I improved performance with caching."

Interviewer: "How much has it improved?"

Applicant: "Um... it seemed to have gotten much faster."

→ Elimination


After

Interviewer: "Do you have experience using Redis?"

Applicant: "Yes, the product lookup API was taking an average of 3 seconds,

Caching the top 1000 products with Redis

It improved by 6 times to 0.5 seconds.

TPS increased 4-fold from 500 to 2000,

DB CPU decreased by 75% from 80% to 20%.

I conducted response time testing with Postman and load testing with JMeter.

Interviewer: "Excellent. By any chance, what about cache misses...?"

→ Pass


Specific Changes

  • Please include 3 or more numbers naturally in your response.

  • Perfect answers in under 1 minute using the A-B-C formula

  • 7 Perfect Responses to Follow-up Questions

  • Mastering Differentiation Strategies by Company

  • "When you don't know" zero silence

I recommend this for people like this

I keep failing interviews,
and I don't know why.
✔ Those who only give abstract answers like "I've used Redis" or "I improved performance"
✔ Those who get stuck on follow-up questions ("Why did you choose that?", "What other methods are there?")

I have projects, but I don't know what or how to talk about them.
✔ Those who want to change "It got much faster" into "specific expressions"
✔ Those who want to turn toy project experiences into interview answers

I know the technology, but I can't explain it.
✔ Those who have used Redis, Kafka, MSA but can't provide reasons for "why they used them"
✔ Those who evaluated only by "feeling" without measuring Before/After metrics

🎁 EVENT 🎁

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

6-Week Complete! 4 Backend Resume Differentiation Strategies - How to Stand Out Among Similar Resumes

We're giving you a 30% discount coupon for that course!

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 Success Community Management and Offline Meetup Operations


Pre-enrollment Reference Information

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

Am I supposed to be listening to this live right now?? If you're wondering about this, feel free to reach out anytime through the open chat room!

😍 I'll do my best to provide you with thorough answers 😍

Practice Environment

  • Learn through questions and answers as if you're taking a real technical interview through live sessions.


Learning Materials

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


Prerequisites and Important Notes

  • At least 1 backend project experience (school assignments, bootcamp, toy projects all acceptable)

  • Experience creating simple APIs with Spring or Node.js

  • Experience studying object-oriented programming, DBMS/RDBMS, cache, and index


11월

7일

챌린지 시작일

2025년 11월 7일 PM 03:00

챌린지 종료일

2025년 11월 10일 PM 02:59

챌린지 커리큘럼

All

11 lectures ∙ (6hr 28min)

Course Materials:

Live

챌린지에서 배워요

  • Practical Methods for Quantifying Project Experience with Numbers

  • Advanced answer tree that handles 2-3 follow-up questions

  • Practical Mock Interview Simulation Experience

Recommended for
these people

Who is this course right for?

  • A backend developer who has a technical interview coming up but feels overwhelmed about what to prepare first

  • A junior developer who experienced a mental breakdown after only answering "ACID..." to the question "What is a transaction?"

  • I've done projects, but I'm a junior developer who can't answer the question "So what were the results?" with numbers

  • Job applicants who keep giving the same answers in every interview and end up getting rejected

Need to know before starting?

  • Spring Boot basic usage experience

  • JPA Basic Usage Experience

Reviews

All

31 reviews

5.0

31 reviews

  • ark1541님의 프로필 이미지
    ark1541

    Reviews 4

    ∙

    Average Rating 5.0

    5

    80% enrolled

    After deciding to change jobs, writing a resume after such a long time was incredibly difficult. The methods for writing resumes have changed a lot since when I first got hired. After taking Dingco's course, I wrote a draft resume and conducted mock interviews, and I'm satisfied because it turned out better than I expected!

    • kyoung16784957님의 프로필 이미지
      kyoung16784957

      Reviews 1

      ∙

      Average Rating 5.0

      5

      100% enrolled

      Thanks to DingCodingCo, I received a lot of help with writing my first resume!!

      • koelkorea7927님의 프로필 이미지
        koelkorea7927

        Reviews 14

        ∙

        Average Rating 5.0

        5

        80% enrolled

        Although it was a short class, I think it was definitely a high-level lecture since only serious people participated live in the class. I think it was an incredibly cost-effective lecture because just by carefully reading the technical interview topic section, you can check exactly what domestic big tech backend positions want.

        • ablekor님의 프로필 이미지
          ablekor

          Reviews 8

          ∙

          Average Rating 5.0

          5

          100% enrolled

          Without experiencing this challenge, preparing my resume and portfolio would have resulted in mediocre outcomes that might as well not have existed. Thanks to this challenge, I think I'll be able to create a good resume and portfolio.

          • hoonti06님의 프로필 이미지
            hoonti06

            Reviews 1

            ∙

            Average Rating 5.0

            5

            100% enrolled

            I was able to learn a lot of resume writing and interview tips, and I think I'll be able to organize the tasks I do at work well!

            FAQs

            취소 및 환불 규정
            챌린지는 지식공유자가 설정한 수업 최소 정원이 충족되지 않을 경우, 폐강 안내가 고지되며 결제 내역이 자동취소됩니다.

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