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Korean & Japanese Engineering Blogs & Communities 2026 — Toss SLASH / Kakao if(kakao) / NAVER D2 / WOOWACON / Mercari / CyberAgent / RubyKaigi / DEVIEW Deep Dive

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Prologue — Why Korea and Japan deserve their own roundup

English-speaking engineering blogs (High Scalability, Netflix Tech Blog, Stripe Engineering, GitHub Engineering, Cloudflare blog) are easy to track if you have a half-decent RSS reader. Korea and Japan are different.

  • Korea: Most content is written in Korean, English translations are sporadic. The hands-on experience at Toss, Kakao, NAVER, Woowa Brothers, and Karrot cannot be caught with an English-only feed.
  • Japan: Japanese content makes up 90%+ of the writing. Only globally minded firms (Mercari, Rakuten, LY) maintain consistent English versions. Yet this is one of the richest pools on the planet for SRE, payment systems, legal compliance, and relational-database operations know-how.

This post maps the must-know Korean and Japanese engineering blogs and tech conferences of 2026 into a single document. Tone, strengths, signature posts, RSS URLs, conference schedules — all in one place.

By the end you should be able to answer:

  • Among Korea's Toss SLASH, Kakao if(kakao), NAVER DEVIEW, WOOWACON, and Karrot meetups — which conference to attend first
  • For Japan's RubyKaigi, BuildersCON, PyCon JP, AWS Summit Japan — how to register and how to follow up on the talks
  • Which Korean or Japanese blog covers your domain (payments, e-commerce, ads, gaming, SaaS) the best

All on a single screen.

1. The 2026 atlas of Korean & Japanese engineering communities

Let's start with the map.

┌──────────────────────────────────────────────────────────────────────┐
│       2026 Atlas — Korean & Japanese Engineering Blogs              │
│                                                                      │
│  Korea — strong in fintech & e-commerce                              │
│   - Toss: tech.toss.im + SLASH conference                            │
│   - Kakao: tech.kakao.com + if(kakao) + Pay/Bank/Enterprise blogs    │
│   - NAVER: D2 + NAVER Engineering Blog + DEVIEW                      │
│   - LINE / LY Corp: engineering.linecorp.com (Korea side)            │
│   - Woowa Brothers: techblog.woowahan.com + WOOWACON                 │
│   - Karrot: medium.com/daangn                                        │
│   - Coupang: medium.com/coupang-engineering                          │
│   - Musinsa / RIDI / Zigbang / Yanolja / Banksalad / Devocean (KT)   │
│                                                                      │
│  Japan — strong in SaaS, internet services, and e-commerce           │
│   - Mercari: engineering.mercari.com                                 │
│   - LY Corporation (LINE Yahoo): techblog.lycorp.co.jp               │
│   - Cybozu / CyberAgent / DMM / DeNA / Recruit                       │
│   - ZOZO / pixiv Inside / Cookpad / Niconico (Dwango)                │
│   - freee / Money Forward / SmartHR / Sansan                         │
│   - Rakuten / Yahoo Japan / Hitachi / NEC / NTT Data / Fujitsu       │
│                                                                      │
│  Headline conferences — Korea and Japan                              │
│   - Korea: DEVIEW / if(kakao) / SLASH / WOOWACON / GopherCon Korea   │
│   - Japan: RubyKaigi / BuildersCON / PyCon JP / Kubernetes Days      │
│           AWS Summit Japan / Google I/O Connect Tokyo                │
└──────────────────────────────────────────────────────────────────────┘

After reading this map, the recommendation is to pick the company closest to your domain (payments, e-commerce, media, SaaS, gaming) and start an RSS subscription there.

Korea vs Japan — what differs

AxisKoreaJapan
Dominant domainsFintech, e-commerce, gamingSaaS, payments, internet services
Blog toneHands-on cases, architectureOperations, validation, high availability
English translationsPartial (Toss, NAVER some)A handful of globally minded firms (Mercari, Rakuten)
Conference scale10k–30k attendees (DEVIEW, if kakao)1k–10k attendees (RubyKaigi, BuildersCON)
Core communitiesOKKY, Facebook groupsQiita, Zenn

Korea wins on tales from fast-moving service operations; Japan wins on validation and SRE wisdom from systems that have been running stably for decades. Reading both delivers a far more balanced view than reading either alone.

2. Korea — Toss (tech.toss.im) + SLASH

Toss (Viva Republica), the king of Korean fintech, has run tech.toss.im since 2018 and reveals 1,000+ talks each fall at the SLASH conference.

tech.toss.im — the textbook of Korean fintech in the field

Highlights:

  • Payments and transfer hands-on experience: PG, simple payments, transfers, credit scoring — a wealth of case studies from running Korean fintech.
  • Incident postmortems: Toss publishes very detailed write-ups of production incidents. The "Toss payment failure retrospective" is a recognized reference in Korean SRE.
  • Wide tech breadth: Kubernetes, Kafka, microservices, Vault, Service Mesh, Cassandra, MongoDB — broader than almost any Korean internet-services blog.
  • Mobile + backend + infra: iOS/Android, server, data, ML all live in one blog. Design system posts are also strong.

SLASH — Korea's RE:Invent

SLASH, held every September or October by Toss, is one of Korea's largest fintech/internet-service conferences. SLASH 23, 24, 25 — each releases 100+ sessions.

Major tracks:

  • Server/Backend: microservices, databases, message queues, transactions
  • Mobile: iOS/Android performance, architecture, testing
  • Frontend: React, React Native, web performance
  • Data & ML: data platforms, real-time analytics, ML operations
  • SRE/DevOps: Kubernetes, deployments, observability
  • Security: Korean fin-security, threat analysis, identity

Talks are posted on the official SLASH site and the Toss YouTube channel with Korean subtitles, free of charge.

Standout posts and sessions

  • "Toss's GraphQL adoption story — how we built our BFF"
  • "Toss's sidecar pattern — Envoy + Service Mesh"
  • "Toss money-transfer outage — how we recovered in 7 seconds"
  • "Toss design system TDS — managing 1,000 components"

These are Korean-only but worth running through machine translation plus an English summary for international colleagues.

3. Korea — Kakao if(kakao) + tech.kakao.com + Kakao Pay/Bank/Enterprise

Kakao runs the most distributed network of engineering blogs among Korean internet firms — the main company plus subsidiaries each maintain their own.

tech.kakao.com — Kakao headquarters blog

Running since 2016. Covers KakaoTalk, KakaoMap, KakaoT, and other HQ services. Kakao's specialty is operating large-scale messaging systems.

  • KakaoTalk backend (Cassandra, Kafka, messaging queues)
  • KakaoMap (map data, search, routing)
  • Kakao T (mobility, real-time matching)
  • Kakao i (AI voice, translation, OCR)

Kakao Pay — tech.kakaopay.com

A payments and finance company, so PG, simple payments, transfers, and credit scoring posts are abundant. Compared to Toss, Kakao Pay writes more about integration with the Kakao ecosystem (KakaoTalk, Melon, Kakao Shopping).

Kakao Bank — tech.kakaobank.com

Korea's first internet-only bank. Posts on banking backend, core-banking systems, FSS (Financial Supervisory Service) compliance, and internal controls. Almost the only public material on Korean banking systems.

Kakao Enterprise — tech.kakaoenterprise.com

B2B SaaS, search, AI. Kakao i Cloud, KakaoWork, search engine. Some businesses were trimmed in 2024 but the blog remains active.

if(kakao) — Kakao's annual conference

Held every fall, if(kakao) is one of Korea's largest tech conferences in terms of session count. if(kakao) 2022, 2023, then if(kakao) AI 2024 each released 200+ sessions.

Highlights:

  • Headquarters, subsidiaries, and affiliates all present at one venue — best survey of Kakao's engineering breadth.
  • Every session is published on if.kakao.com with Korean subtitles, free to watch.
  • No registration fee — pre-registration alone unlocks every asset.

4. Korea — NAVER D2 + NAVER Engineering Blog

NAVER runs the oldest engineering blog in Korea. NAVER D2 (d2.naver.com) has been live since 2013, and NAVER Engineering (engineering.naver.com) is now also running in parallel.

NAVER D2 — depth in search, platform, and language

NAVER D2's strengths are search, NLP, language models, and DBMS. For Korean-language NLP, D2 has the biggest open archive in the country.

Notable areas:

  • Korean NLP: morpheme analyzers, BERT, HyperCLOVA, HyperCLOVA X
  • Search: indexing, ranking, real-time indexing
  • Mobile/Web: NAVER app, Whale browser, NAVER Webtoon
  • Infrastructure: CUBRID, CloudDB, CXL, GPU clusters

NAVER Engineering Blog — newer brand

In the 2020s NAVER added a new brand, NAVER Engineering, focusing on NAVER Cloud, NAVER Pay, NAVER Label, and LINE-related material.

DEVIEW — the original Korean tech conference

DEVIEW started in 2008. Paused during COVID, then back as DEVIEW 23 (Feb–Mar 2024) and DEVIEW 24. The oldest Korean tech conference, and the one that has witnessed the most generational change in the industry.

Highlights:

  • Strong tracks on search, NLP, language models, and platforms.
  • All sessions published on deview.kr with Korean subtitles, free.
  • Registration free; just pre-register.

Signature posts

  • "HyperCLOVA — building a giant Korean language model"
  • "Korean search — balancing accuracy and speed"
  • "NAVER Webtoon recommendation system"
  • "25 years of CUBRID"

5. Korea — LINE / LY Corp Engineering Blog

LINE used to run engineering blogs in both Korea and Japan. After the 2023 merger that became LY Corporation, Japan-side content moved to techblog.lycorp.co.jp; the Korea-side blog at engineering.linecorp.com continues at LINE Plus.

Korea-side LINE Engineering — LINE Plus

LINE Plus, a subsidiary of LY Corp, builds for Japan, Korea, and Southeast Asia. The Korean blog's strengths:

  • Messaging backend: LINE is the dominant messenger in Japan, Thailand, Taiwan, and Indonesia with 500M+ users. The message-queue, push, and encryption know-how is hard to find anywhere else in Korea.
  • LINE Pay: Payments in Japan, Taiwan, and Thailand.
  • LINE Manga / LINE Webtoon: Content platform operations.
  • LINE Game / LINE NEXT (Web3): Gaming and blockchain divisions.

A noteworthy share of posts are published in both Korean and English — one of the most accessible Korean company blogs for English speakers.

Changes after the LY merger

After the LINE Yahoo merger in October 2023, Japan-side LINE Engineering was consolidated into techblog.lycorp.co.jp. The Korea-side engineering.linecorp.com stays separate, focused on Korea and Southeast Asia content.

There was talk in 2024–2025 about NAVER divesting its LY Corp stake, but as of 2026 the LINE Plus engineering organization in Korea remains stable.

6. Korea — Woowa Brothers Tech Blog + WOOWACON

Woowa Brothers (operator of Baedal Minjok, "Baemin") publishes the largest body of backend, DDD, and MSA posts among Korean companies.

techblog.woowahan.com

Highlights:

  • DDD / event sourcing: Baemin's monolith-to-microservices migration is one of the most detailed case studies in Korea.
  • JPA / Spring Boot: A de-facto textbook for Korean Java engineers.
  • Kafka and event-driven: Lots of posts dissecting the ordering and delivery domains as events.
  • Data platform: Plenty of data engineering, Airflow, and Dagster cases.

WOOWACON

Woowa Brothers' annual conference, launched in 2017. WOOWACON 2024 and 2025 followed. Backend, infrastructure, data, and DX tracks are strong.

Highlights:

  • All session videos posted free on woowacon.com.
  • Free registration, pre-registration required.
  • Sessions about Woowa Brothers' internal engineering culture (Woowahan Techcourse) are included.

Standout posts

  • "Baemin's microservices journey"
  • "Solving the JPA N+1 problem"
  • "Event sourcing and CQRS — applied to ordering"
  • "Woowa data platform — from BigQuery to Snowflake"

7. Korea — Karrot / Coupang / Musinsa / RIDI / Yanolja / Zigbang / Smilegate / Pearl Abyss / Banksalad / Devocean (KT)

Behind Toss, Kakao, NAVER, LINE, and Woowa Brothers, Korea has a deep bench of domain-specific blogs.

Karrot (Daangn Market)

Runs on medium.com/daangn. Korea's #1 second-hand goods and hyperlocal service. Strengths:

  • Machine learning: fraud detection, recommendation, image recognition
  • Hyperlocal: caching and lookup patterns for location-based services
  • Global expansion: lessons from Japan, Canada, and the UK

Coupang Engineering

Runs on medium.com/coupang-engineering. Korea's #1 e-commerce platform, listed on NYSE. Strengths:

  • Rocket Delivery infrastructure: fulfillment, last-mile, real-time dispatch
  • Search and ranking: a de-facto standard for Korean e-commerce search
  • Payments: Coupang Pay's payment system

Among Korean companies, Coupang has one of the highest ratios of bilingual (English) posts.

Musinsa Tech

Runs on medium.com/musinsa-tech. Korea's #1 fashion e-commerce. Strengths:

  • E-commerce backend: orders, inventory, payments
  • Content platform: Musinsa stories, UGC, live commerce
  • Mobile app: UX cases from Korea's #1 fashion app

RIDI Tech Blog

Runs on ridicorp.com/story/tech. Korea's #1 e-books and webtoon platform. Strengths:

  • Content platform: metadata and search for books, webtoons, web novels
  • Payments and subscriptions: recurring models and overseas payments

Yanolja

Runs on medium.com/yanolja-tech. Korea's #1 travel and hotel platform, pursuing a Nasdaq listing. Strengths:

  • Travel search and reservation: integrated search for hotels, flights, and rental cars
  • Global PMS: Yanolja Cloud's hotel-management system
  • Data platform: big-data cases from the Korean travel domain

Zigbang

Runs on medium.com/zigbang. Korea's #1 real-estate platform. Strengths:

  • Real-estate data: listings, market prices, transaction records
  • Mobile app: maps, VR, AR-driven real-estate exploration

Smilegate / Pearl Abyss — gaming engineering

Smilegate (engine team) and Pearl Abyss (Black Desert) are rare examples of Korean game studios running engineering blogs. Game backends, shaders, physics engines, MMO synchronization — content that is hard to find on any other IT-company blog.

Banksalad

Acquired by Shinhan Card in 2022, Banksalad is a first-generation Korean MyData/fintech company. Posts at blog.banksalad.com. Strengths:

  • MyData and open banking: leveraging Korea's MyData API
  • Personalized recommendations: cards, deposits, loans
  • Data engineering

Devocean — telecom-driven blog

Devocean (devocean.sk.com) is operated by SK Telecom and is the flagship Korean telco tech blog. Cloud, networking, 5G, AI — heavy on those. (Note: KT also operates a separate Devocean-branded blog. The two telecoms together form the de facto twin pillars of Korean telco-infrastructure blogging.)

8. Korean conferences — DEVIEW / if(kakao) / SLASH / WOOWACON / GopherCon Korea / PyCon Korea

A single-page map of Korean tech conferences.

Company-hosted conferences

ConferenceHostSeasonNotes
DEVIEWNAVERFeb–MarThe original Korean tech conference — search, NLP, platform
if(kakao)KakaoSep–OctLargest session count, HQ + subsidiaries combined
SLASHTossSep–OctHands-on fintech and MSA, rising fast
WOOWACONWoowa BrothersNovemberBackend, DDD, data
FE ConferenceKakao Enterprise et alIrregularFrontend
LINE DEV WEEKLY CorpIrregularLINE group umbrella

Community-hosted conferences

ConferenceSeasonNote
PyCon KoreaAug–OctKorean Python community
GopherCon KoreaOct–NovKorean Go community
KubeCon + CloudNativeCon KoreaDecemberKorean CNCF
JavaScript Korea / FEConfIrregularKorean JS/frontend
AWS Summit SeoulMayAWS Korea
Google I/O Extended SeoulMay–JunGoogle Korea
Microsoft Ignite KoreaNovemberMicrosoft Korea

Which conference to attend first

The main filter is your own domain.

  • Fintech / payments: SLASH > if(kakao) > WOOWACON
  • E-commerce / search: DEVIEW > if(kakao)
  • Backend / MSA: WOOWACON > SLASH > if(kakao)
  • Data / ML: DEVIEW > SLASH
  • Mobile: SLASH > if(kakao)
  • DevOps / SRE: SLASH > if(kakao) > KubeCon Korea
  • Language community: PyCon Korea / GopherCon Korea

9. Japan — Mercari Engineering Blog

The flagship of Japanese engineering blogs is Mercari. engineering.mercari.com publishes a lot in English, making it the most accessible Japanese engineering blog by far.

Mercari's strengths

  • Microservices: One of the most detailed accounts anywhere of a monolith-to-200+-microservices migration, beginning in 2017.
  • Payments and finance: Merpay's payment, transfer, and Buy Now Pay Later systems.
  • Global expansion: Mercari US, Origami (India), and other global cases.
  • Machine learning: search, ranking, image recognition, fraud detection.
  • Data infrastructure: BigQuery, Looker, dbt usage.

English vs Japanese ratio

About 60–70% of Mercari's posts are in English — the highest share of any Japanese engineering blog. Many English posts are write-ups of talks delivered at English-speaking SaaS or fintech conferences.

Signature posts

  • "Mercari's Microservices Architecture — 5 Years Later"
  • "How Merpay Built Buy Now Pay Later in Japan"
  • "Mercari US — Lessons from Expanding to the US Market"
  • "From Monolith to Microservices — A Complete History"

Mercari Tech Conf

Mercari has run Mercari Tech Conference since 2018. Held in Tokyo every fall, it features more English sessions than most Japanese tech conferences.

10. Japan — LY Corporation Tech Blog (the 2023 LINE Yahoo merger)

After LINE and Yahoo Japan merged in October 2023, the combined entity LY Corporation now publishes at techblog.lycorp.co.jp.

LY Corp's reach

  • More than 70% of Japanese internet users touch LINE or Yahoo Japan
  • LINE has 500M+ users (Japan, Thailand, Taiwan, Indonesia)
  • Yahoo Japan is Japan's top portal, e-commerce site, and news site
  • Subsidiaries include PayPay (payments), Yahoo Shopping, ZOZOTOWN (folded in 2024), eBookJapan, and more

Strengths of the tech blog

  • Messaging backend: LINE's operational know-how
  • Payments: PayPay, LINE Pay, Yahoo Wallet integration
  • Advertising: RTB and DSP for Yahoo Ads and LINE Ads
  • Search and paid search: Yahoo Japan search (the #1 Japanese search engine, distinct from Google)
  • E-commerce: Yahoo Shopping and the PayPay Mall

Changes on the Japan-side LINE Engineering

Before the 2023 merger, Japan-side LINE Engineering Blog (engineering.linecorp.com/ja) was also active. After the merger Japan-side content moved to the LY Tech Blog, while Korea-side LINE Plus continues on engineering.linecorp.com.

LINE DEV WEEK / LINE DEVELOPER DAY

LINE DEVELOPER DAY ran since 2015 and has evolved into LINE DEV WEEK post-merger. Held simultaneously in Tokyo and Seoul in many years, with a portion of sessions in English.

11. Japan — Cybozu / CyberAgent / DMM / DeNA / Recruit

The longest-running Japanese engineering blogs.

Cybozu Tech Blog — blog.cybozu.io

Cybozu is the original Japanese SaaS company. Its kintone, Cybozu Office, and Garoon products lead the Japanese corporate market. Strengths:

  • SaaS operations: handling the demanding requirements of Japanese enterprise customers
  • On-prem + cloud coexistence: kintone is cloud, Garoon runs both ways
  • Language coverage: Go, Java, TypeScript, React, Vue.js
  • OSS contribution: Cybozu is a major contributor to Japanese OSS, especially the Go ecosystem

CyberAgent Developers Blog (Ameba)

developers.cyberagent.co.jp. CyberAgent is a leader in Japanese advertising, media, and gaming. Ameba Blog, AbemaTV, games — wide-ranging. Strengths:

  • Advertising and DMP: operational know-how in the Japanese ad market
  • AbemaTV: live-streaming infrastructure for Japanese OTT
  • Game backend: mobile game operations
  • Machine learning and generative AI: CyberAgent AI Lab's LLM research

DMM tech blog — inside.dmm.com

DMM is a diversified Japanese internet conglomerate — video, gaming, cryptocurrency (DMM Bitcoin), online English education. Strengths:

  • Payment system operations
  • Video streaming infrastructure
  • Crypto-exchange operational know-how (DMM Bitcoin)

DeNA Engineering Blog — engineering.dena.com

DeNA was a first-generation Japanese mobile game company. Now diversified into baseball, healthcare, and auto. Strengths:

  • Game-operations infrastructure: Japanese mobile-game ops know-how
  • Machine learning and generative AI: healthcare and auto AI cases
  • AWS and GCP use cases

Recruit Tech Blog — blog.recruit.co.jp/data

Recruit Holdings is Japan's top HR and internet-services group, also parent of Indeed and Glassdoor. Strengths:

  • Search and matching: job-search cases at Japanese and global scale
  • Data platform: recommendation, ranking, data engineering
  • Indeed global operations

12. Japan — ZOZO / pixiv Inside / Cookpad / Niconico (Dwango)

Japanese content and lifestyle-domain blogs.

ZOZO Tech Blog — techblog.zozo.com

ZOZO (operator of ZOZOTOWN) is Japan's #1 fashion e-commerce. Acquired by Yahoo Japan (now LY Corp) in 2019. Strengths:

  • E-commerce search and recommendation: Japanese fashion-domain cases
  • 3D measurement and avatars: ZOZOSUIT and ZOZOMAT IoT-measurement data usage
  • Image search: fashion category classification, similar-item recommendation

pixiv Inside — inside.pixiv.blog

pixiv is the leading Japanese illustration and manga community. Strengths:

  • Image and video processing: large-media operations
  • Tagging and search: dealing with the quirks of Japanese-language tags
  • Payments and subscriptions

Cookpad Tech Blog — techlife.cookpad.com

Cookpad is Japan's #1 recipe-sharing service. Strengths:

  • Ruby on Rails: Cookpad is a giant in the Japanese Ruby ecosystem with multiple Rails core committers
  • Data infrastructure
  • Search and NLP: the specifics of Japanese-language recipe search
  • Global service operations

Niconico (Dwango) Tech Blog — blog.nicovideo.jp

Operator of Niconico Douga and first-generation Japanese OTT. Strengths:

  • Live streaming with comment synchronization: Niconico's overlay comments are an icon of Japanese internet culture
  • 2024 cyber-attack retrospective: Dwango published a write-up of a major ransomware attack in June 2024 and the recovery process. A high-value Japanese IT security case study.

13. Japan — freee / Money Forward / SmartHR / Sansan — Japanese SaaS

In the 2020s Japanese SaaS companies began publishing engineering content in earnest. Essential reading for the Japanese B2B SaaS domain.

freee Developers Blog — developers.freee.co.jp

freee leads Japanese cloud accounting SaaS. Listed on the Tokyo Stock Exchange Mothers (now Growth) in 2019. Strengths:

  • Accounting and tax domain: handling Japanese accounting standards and tax law
  • Rails + microservices
  • Data engineering: integrating Japanese corporate data

Money Forward Engineering Blog — moneyforward-dev.jp

Money Forward provides personal-finance and corporate-accounting SaaS in Japan. Strengths:

  • Financial-data integration: integrating Japanese bank, card, and securities data (analogous to Korea's MyData)
  • Multi-language stack: Ruby, Go, TypeScript
  • SRE and observability

SmartHR Tech Blog — tech.smarthr.jp

SmartHR is Japan's leading HR SaaS. Strengths:

  • HR and labor domain: handling Japanese labor law and social insurance
  • TypeScript and React frontends
  • Design system: SmartHR UI is essentially a Japanese SaaS design-system standard

Sansan Tech Blog — buildersbox.corp-sansan.com

Sansan leads the Japanese business-card management SaaS market. Strengths:

  • OCR and image recognition: turning business-card images into digital text
  • AI and NLP: Japanese-language NLP applications
  • B2B SaaS operations

Japan's SaaS Big Four — vs Korean counterparts

CompanyDomainKorean comparison
freeeAccounting SaaSDouzone Bizon, Wehago
Money ForwardPersonal & corporate financeBanksalad, Brique
SmartHRHR SaaSShiftee, FLEX
SansanBusiness-card managementRemember (리멤버)

This is the cluster a Korean SaaS engineer should read most carefully — the domains overlap.

14. Japan — Rakuten / Yahoo Japan / Hitachi / NEC / NTT Data / Fujitsu — JTC giants

JTC (Japanese Traditional Company) engineering blogs work differently from internet-company blogs.

Rakuten Tech Blog — engineering.rakuten.com

Rakuten is famous for its English-as-the-corporate-language policy. Together with Mercari it has the highest English-publication ratio. Strengths:

  • E-commerce: Rakuten Ichiba operations
  • Payments and finance: Rakuten Card, Bank, Securities
  • Mobile telecom: Rakuten Mobile (notable for its Open RAN build-out)
  • Global R&D: Tokyo, New York, Paris, Bangalore

Yahoo Japan Tech Blog → folded into LY Corp

Before the 2023 LY merger, Yahoo Japan ran techblog.yahoo.co.jp. Post-merger it consolidated into the LY Corp Tech Blog.

Hitachi / NEC / NTT Data / Fujitsu — the Big Four Japanese SIers

Each of Japan's four major SIers runs its own engineering content.

  • NTT Data: Global blogs at nttdata.com/global/en/news/blog. Case studies in Japanese government, finance, and manufacturing SI.
  • Hitachi: hitachi.com/products/it/research. Japanese manufacturing and industrial IT.
  • NEC: nec.com/en/global/insights. Cloud and AI solutions.
  • Fujitsu: blog.fujitsu.com. Fujitsu Cloud, AI, quantum computing.

Their tone differs from internet-company blogs, but they show what the de-facto Japanese enterprise-IT standards really look like.

15. Japanese conferences — RubyKaigi / BuildersCON / PyCon JP / Kubernetes Days Tokyo / AWS Summit Japan

The single-page map of Japanese tech conferences.

Language-community conferences

ConferenceSeasonNote
RubyKaigiMayThe flagship of Japan's Ruby community, many English sessions
PyCon JPSep–OctJapanese Python community
YAPC::JapanIrregularJapanese Perl and dynamic-language community
Vue.js Fes JapanIrregularJapanese Vue.js community
JSConf JPNov–DecJapanese JavaScript community

Company / platform conferences

ConferenceHostSeason
Mercari Tech ConferenceMercariAutumn
LINE DEV WEEKLY CorpIrregular
CyberAgent Developer ConferenceCyberAgentIrregular
AWS Summit JapanAWSJune
Google I/O Connect TokyoGoogleJun–Jul
Microsoft Build JapanMicrosoftNov–Dec

Infra / DevOps conferences

ConferenceSeason
Kubernetes Days Tokyo / CloudNative Days TokyoNov–Dec
BuildersCON TokyoIrregular
Developers Summit (Devsumi)February
Open Source Summit JapanDecember

RubyKaigi — Japan's most international tech conference

RubyKaigi is the most international Japanese tech conference. It's held in a different city each year (Okinawa in 2024, Matsumoto in 2025, TBD in 2026). Core Ruby developers including Matz attend; more than half of sessions are in English.

Highlights:

  • International: many English sessions, sizable share of overseas attendees
  • Ruby core developers attend: Matz, Yusuke Endoh, Koichi Sasada, and others
  • Ticket price: roughly JPY 30,000–40,000. Higher than typical Japanese conferences, but worth it.

AWS Summit Japan / Google I/O Connect Tokyo

Global platform vendors' Japan events run every June or July at Tokyo Big Sight or Tokyo International Forum. Same format as AWS Summit Seoul, but heavier on Japanese enterprise case studies.

16. RSS recommendations — what to subscribe to first

If the list above feels overwhelming, here is a domain-specific starter pack.

Fintech / payments — top 5

  1. tech.toss.im (Korea)
  2. engineering.mercari.com (Japan, in English)
  3. tech.kakaopay.com (Korea)
  4. tech.kakaobank.com (Korea)
  5. developers.freee.co.jp (Japan)

E-commerce / search — top 5

  1. medium.com/coupang-engineering (Korea, partially in English)
  2. techblog.zozo.com (Japan)
  3. medium.com/musinsa-tech (Korea)
  4. engineering.rakuten.com (Japan, in English)
  5. d2.naver.com (Korea)

Backend / MSA / platform — top 5

  1. techblog.woowahan.com (Korea)
  2. blog.cybozu.io (Japan)
  3. tech.toss.im (Korea)
  4. tech.kakao.com (Korea)
  5. engineering.mercari.com (Japan, in English)

Data / ML — top 5

  1. d2.naver.com (Korea)
  2. medium.com/daangn (Korea)
  3. inside.dmm.com (Japan)
  4. developers.cyberagent.co.jp (Japan)
  5. blog.recruit.co.jp/data (Japan)

SaaS ops / design systems — top 5

  1. tech.smarthr.jp (Japan)
  2. tech.toss.im (Korea)
  3. blog.cybozu.io (Japan)
  4. moneyforward-dev.jp (Japan)
  5. buildersbox.corp-sansan.com (Japan)

Mobile / gaming — top 5

  1. medium.com/coupang-engineering (Korea, mobile)
  2. techlife.cookpad.com (Japan, mobile)
  3. blog.smilegate.com (Korea, gaming)
  4. blog.pearlabyss.com (Korea, gaming)
  5. engineering.dena.com (Japan, gaming)

17. Following Japanese-only blogs with translation — a workflow

A large portion of Japanese blogs are Japanese-only; Korean blogs are also overwhelmingly Korean-only. Here is a workflow for sharing them with English-speaking colleagues or for your own English notes.

Translation tools

  • DeepL: best quality for Japanese, Korean, and Chinese to English. The free tier is enough.
  • Google Translate: fast first pass. Lower accuracy than DeepL but faster.
  • Claude / GPT: best for long-document summarization or rewriting into natural English, beyond literal translation.
  • Readability + translator: pair Pocket or Readwise with a translator.

English-note workflow

  1. Read the Japanese or Korean original
  2. Capture 5–10 bullets in English (Notion, Obsidian, etc.)
  3. Share with the team: original link + English summary + a one-line take

Run that loop for a month and you'll have a regular channel for surfacing Japanese and Korean engineering content to your English-speaking team.

Subscribe to the higher-English-ratio blogs first

For a soft landing, subscribe to the blogs with the highest English ratios first.

  • Mercari: 60–70% English
  • Rakuten: 50%+ English
  • LINE Plus (Korea): 30–40% English
  • Coupang: 30–40% English
  • NAVER D2 (subset): 20–30% English

Then supplement with Japanese- or Korean-only blogs in your domain via translation.

Closing — the value of reading both sides

Geographically and culturally Korea and Japan are close, but their engineering strengths diverge.

  • Korea brings hands-on experience from fast-moving service operations (fintech, e-commerce, gaming).
  • Japan brings validation and SRE wisdom from systems that have run stably for decades (SaaS, payments, internet services).

Reading both unlocks a layer that English-only feeds (High Scalability, Stripe, Netflix, Cloudflare) miss. Particularly if you serve Korean or Japanese users, these are essentially required reading.

Start with the RSS list in this post, expand to your domain, and pencil the spring and autumn conference seasons into your calendar.

The next post in this series will give the same treatment to English-speaking, Chinese-speaking, and Southeast Asian engineering blogs.

References

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