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Intro: 2026, the Year Japanese Tech Finally Opened Up to Foreign Engineers

The 2026 Tokyo/Osaka tech hiring market is more open to foreign engineers than ever. Mercari has run on English as the in-house language for over five years. LINE, now under the NAVER-SoftBank joint structure, mixes Korean, Japanese, Taiwanese, and Thai engineers daily. ZOZO, CyberAgent, PayPay, Rakuten, DeNA — all pushed foreign engineer ratios into double-digit percentages, and full-remote senior reviewers in Seoul approving Tokyo HQ pull requests are no longer a rarity.

The catch is the gray zone: "code is global but meetings are Japanese, the wiki is Japanese, and Slack mentions are Japanese." Even at English-meeting companies, lunch chat, 1on1s, and the incident Slack channel still flow in Japanese. And the first time you mistype "otsukaresama desu" the room goes quiet for five seconds.

This guide is for non-Japanese engineers surviving a Japanese IT company (or Japanese subsidiary). It covers 24 scenarios with Japanese example sentences, romaji, English meaning, and the timing of when to use each. It is not a vocabulary list; the goal is cultural calibration — what impression each tone leaves.

1. Greetings: Otsukaresama desu vs Otsukaresama vs Gokurousama

The most-heard and most-confused greeting. A literal "thanks for your hard work," but in Japan the choice depends on time of day, hierarchy, and channel (text vs spoken).

| --- | --- | --- | --- | --- |

**A common mistake**: at modern companies like Mercari or LINE you do not need to prefix every Slack message with "otsukaresama desu" — jumping straight into the body is considered efficient. But at JTC (Japanese Traditional Company) shops like Rakuten or NTT Data, the greeting at every message is still the norm.

2. The Politeness Ladder: Shouchi vs Ryoukai vs Kashikomarimashita

The single English word "understood" splits into 4-5 Japanese tiers. A Korean engineer who only knows "ryoukai desu" can sound flippant to senior staff.

| --- | --- | --- | --- |

**Tip**: the view that "ryoukai" is rude toward superiors is a relatively recent urban legend (originating in 2010s manner books). Mercari does not care; financial-sector clients still expect "shouchi shimashita."

3. Asking for Something: Gokakunin Onegai Shimasu / Yoroshiku Onegai Itashimasu

PR merge requests, doc reviews, data confirmations — "please confirm" makes up 80% of Japanese business communication.

| --- | --- | --- | --- |

**A common pitfall**: literally translating "please confirm" as "kakunin onegai shimasu" without the "go-" prefix sounds slightly command-like. Always attach "go-" to make it "gokakunin onegai shimasu."

4. Slack/Chatwork Etiquette Vocabulary

[Slack message example - polite]

お疲れさまです、@田中さん。

決済APIの障害の件、再現手順を共有させていただきます。

お手数ですが、ご確認いただけますでしょうか。

1. /payments/v2/charge にPOST

2. amount = 0 を含めると500エラー

3. ログは添付の通り

何卒よろしくお願いいたします。

[Slack message example - casual (Mercari style)]

@tanaka 決済APIのバグっぽいの見つけました、見てもらえますか?

- amount=0 で500

- ログ: thread

お願いします!

Frequently used Slack vocabulary:

| Expression | Romaji | Meaning |

| --- | --- | --- |

| なるはや | naru haya | ASAP (Japanese take) |

| 別件ですが | bekken desu ga | On a separate matter (topic switch) |

| ご相談 | gosoudan | Consultation (often a Slack channel name) |

| 共有 | kyouyuu | Share (information sharing) |

| 認識合わせ | ninshiki awase | Align understanding (sync up) |

| お時間ある時に | ojikan aru toki ni | When you have time |

| ご教示ください | gokyouji kudasai | Please teach me (asking for expertise) |

| 取り急ぎ | toriisogi | For now, quickly (email closing) |

| FYI / 念のため | nen no tame | For your reference / just in case |

**Tip**: "naru haya" is informal in-house lingo — never use it in email. Slack and Chatwork only.

5. Code Review: The Japanese Version of the LGTM Ladder

In Japanese dev culture, "LGTM" in English is common, but mixing in Japanese phrasing for senior reviewers or external partners feels more natural.

| --- | --- | --- | --- |

**Shiteki vs Teian**: "shiteki" (指摘, pointing out) is read as a strong word in Japanese review culture. "Teian" (提案, suggestion) or just "comment" lands more softly.

[Code review comment examples]

Soft tone (suggestion)

こちらの関数名、`fetchUser` よりも `getUserById` の方が分かりやすいかもしれません。

お時間ある時にご検討ください。

Standard tone (change request)

こちらの実装ですが、null のケースが考慮されていないように見えます。

ガード句を追加していただけますでしょうか。

Strong tone (blocker)

こちらはセキュリティ上の問題があるため、マージ前に修正をお願いいたします。

具体的には、ユーザーのメールアドレスがログに出力されています。

LGTM

LGTM です。マージしていただいて結構です。

Praise

このリファクタリング、とても読みやすくなりました。素晴らしいです!

6. Meeting Types: Meeting vs Uchiawase vs MTG vs Asakai vs Yuukai

In Japanese companies, the single word "meeting" splits into five or more Japanese words.

| --- | --- | --- | --- |

**Tip**: "uchiawase" carries the nuance of "several people gathering to coordinate" — typically 2-5 attendees rather than 1-on-1.

7. Gijiroku (Meeting Minute) Template

Meeting minutes are core to Japanese company culture. Even foreign engineers, when hosting a meeting, may be asked to write the minutes in Japanese.

議事録: 決済システムv2 設計レビュー

日時

2026/05/16 (金) 14:00〜15:00

参加者

- 田中(PdM)、佐藤(EM)、金(BE)、Lee(QA)

アジェンダ

1. v2 アーキテクチャ概要

2. マイグレーション計画

3. リスクと対応策

決定事項

- マイグレーションはBlue-Green方式で実施

- 期限: 2026年Q3末

- オーナー: 金

ToDo

- [ ] @金詳細設計書作成 (期限: 5/30)

- [ ] @佐藤 SREチームとキャパシティ調整 (期限: 5/23)

- [ ] @Lee QA計画策定 (期限: 6/6)

次回

2026/05/30 (金) 14:00〜

**Minutes vocabulary**:

| Expression | Romaji | Meaning |

| --- | --- | --- |

| 議事録 | gijiroku | Meeting minutes |

| 決定事項 | kettei jikou | Decisions made |

| ToDo / タスク | todo / tasuku | Action items |

| 宿題 | shukudai | Homework (to investigate by next meeting) |

| ペンディング | pendingu | Pending |

| 持ち帰り | mochikaeri | Take back (cannot decide now) |

| 確認事項 | kakunin jikou | Items to confirm |

| ファシリ | fashiri | Facilitator |

8. Furikaeri (Retrospective): KPT and YWT

The most commonly used retro frameworks in Japanese IT teams.

KPT retro

- K (Keep): things to keep doing

- P (Problem): problems

- T (Try): things to try next

YWT retro (Japan-native)

- Y (Yatta koto): what we did

- W (Wakatta koto): what we learned

- T (Tsugi yaru koto): what to do next

Fun/Done/Learn

- Fun: what was fun

- Done: what got done

- Learn: what we learned

| Expression | Romaji | Meaning |

| --- | --- | --- |

| ふりかえり | furikaeri | Retrospective, looking back |

| 振り返り | furikaeri | (Same, kanji form) |

| KPT | kee pii tii | Keep/Problem/Try |

| YWT | wai daburu tii | Yatta / Wakatta / Tsugi yaru |

| レトロスペクティブ | retorosupekutibu | Retrospective |

| スプリントレビュー | supurinto rebyuu | Sprint review |

**Tip**: hiragana "furikaeri" feels softer; kanji "furikaeri" lands more formal in documents. Both are correct.

9. QA / Testing: Tantai, Ketsugou, UAT, Regression

Test types are sometimes loanwords, but JTC-leaning companies prefer the kanji forms.

| --- | --- | --- | --- |

**Tip**: "QA passed" is phrased as "QA wo pasu shita" or "QA OK ga deta."

10. Bug Reports: Saigen Tejun, Kitaichi, Jissokuchi

The Japanese bug report template is nearly standardized across companies.

バグレポート: 決済API 500エラー

概要

amount=0 を含むリクエストで500エラーが返る

再現手順

1. POST /api/v2/payments

2. body に amount=0 を含める

3. 500エラーが返る

再現性

100% (10/10回)

期待値

400 Bad Request エラー、メッセージは "amount must be greater than 0"

実測値

500 Internal Server Error、スタックトレース添付

環境

- 本番環境 (production)

- API version: v2.3.1

- 発生日時: 2026/05/15 14:23 JST

影響範囲

全ユーザーの amount=0 リクエスト (約 3% / day)

暫定対応

クライアント側で amount > 0 のバリデーションを追加 (5/15 リリース済み)

恒久対応

サーバー側でバリデーションを実装 (Issue #1234)

**Core vocabulary**:

| Expression | Romaji | Meaning |

| --- | --- | --- |

| 再現手順 | saigen tejun | Reproduction steps |

| 再現性 | saigensei | Reproducibility |

| 期待値 | kitaichi | Expected value |

| 実測値 | jissokuchi | Actual value |

| 影響範囲 | eikyou hani | Affected scope |

| 暫定対応 | zantei taiou | Temporary fix |

| 恒久対応 | koukyuu taiou | Permanent fix, root-cause fix |

| ワークアラウンド | waakuaraundo | Workaround |

11. Incident Response: Shougai-Taiou Vocabulary

[Slack #incident channel example]

[14:23] 田中: @here 決済APIで500エラー多発中、調査開始します

[14:25] 田中: ステータス: 確認中 (調査中)

[14:31] 田中: 原因: DBコネクションプール枯渇の可能性、リソース確認中

[14:42] 田中: 暫定対応: 該当インスタンスを再起動、エラー率は0.1%まで低下

[14:55] 田中: 復旧確認、モニタリング継続

[15:30] 田中: 完全復旧確認、インシデントクローズ

[翌日] 田中: ポストモーテム書きました → [link]

**Incident vocabulary**:

| Expression | Romaji | Meaning |

| --- | --- | --- |

| 障害 | shougai | Outage, failure |

| 障害対応 | shougai taiou | Incident response |

| インシデント | inshidento | Incident |

| 復旧 | fukkyuu | Recovery |

| ロールバック | roorubakku | Rollback |

| 切り戻し | kirimodoshi | Revert (native Japanese for rollback) |

| ポストモーテム | posuto moutemu | Postmortem |

| RCA | aaru shii ee | Root Cause Analysis |

| 根本原因分析 | konpon gen-in bunseki | Root cause analysis (kanji form) |

| 暫定リリース | zantei ririisu | Hotfix release |

| ホットフィックス | hotto fikkusu | Hotfix |

| エスカレーション | esukareeshon | Escalation |

| 監視 | kanshi | Monitoring |

| アラート | araato | Alert |

**Tip**: "kirimodoshi" is the native Japanese term for rollback, common at JTC firms. Modern companies like Mercari and LINE just say "roorubakku."

12. 1on1, Evaluation, OKR Vocabulary

The 1on1 has become standard at modern Japanese IT companies. Some vocabulary overlaps with Korean usage but diverges in nuance.

| Expression | Romaji | Meaning |

| --- | --- | --- |

| 1on1 | wan on wan | One-on-one meeting |

| 評価 | hyouka | Evaluation, performance review |

| 目標設定 | mokuhyou settei | Goal setting |

| 期初 | kisho | Start of quarter |

| 期末 | kimatsu | End of quarter |

| 上期 / 下期 | kamiki / shimoki | First/second half |

| OKR | oo kee aaru | OKR |

| MBO | emu bii oo | Management by Objectives |

| グレード | gureedo | Grade (level) |

| 昇格 | shoukaku | Promotion |

| 昇給 | shoukyuu | Raise |

| キャリアパス | kyaria pasu | Career path |

| フィードバック | fiidobakku | Feedback |

| 振り返り | furikaeri | (Personal) reflection |

**Tip for non-Japanese engineers**: "hyouka" carries a heavier weight than the English "evaluation." Asking "how is my hyouka going?" in a 1on1 sounds blunt. "Konki no fiidobakku wo itadakemasu ka" ("could I get feedback on this period?") lands much more naturally.

13. JTC vs Mega-Venture: Industry Geography Vocabulary

| Expression | Romaji | Meaning |

| --- | --- | --- |

| JTC | jee tii shii | Japanese Traditional Company |

| 大企業病 | daikigyou byou | Big-company disease |

| メガベンチャー | mega benchaa | Mega-venture (Mercari, LINE, etc.) |

| スタートアップ | sutaato appu | Startup |

| 上流 | jouryuu | Upstream (requirements, design phase) |

| 下流 | karyuu | Downstream (development, test phase) |

| SES | esu ii esu | System Engineering Service |

| 客先常駐 | kyakusaki jouchuu | On-site at client (dispatch) |

| 元請け | motouke | Prime contractor |

| 下請け | shitauke | Subcontractor |

| 孫請け | magouke | Sub-subcontractor |

| 多重下請け | tajuu shitauke | Multi-tier subcontracting |

| 派遣 | haken | Dispatched worker |

| 業務委託 | gyoumu itaku | Outsourced contract (freelancer) |

| 正社員 | seishain | Full-time employee |

| 契約社員 | keiyaku shain | Contract employee |

**A trap to know**: the Japanese IT industry is structured around SI, SES, and multi-tier subcontracting. Targeting in-house product companies (Mercari, LINE, CyberAgent) is the common career move — "never go to SI" is treated as folk wisdom.

14. Katakana IT Vocabulary Dictionary

| --- | --- | --- | --- |

**Tip**: even in Japanese-language meetings, 30-50% of nouns are katakana. Sentences like "agile ni sprint wo mawashite refactoring wo deploy" flow naturally.

15. Nijuu Keigo (Double Honorifics) — the Politeness Trap

Trying to be too polite and over-stacking honorifics creates awkward Japanese. Non-native speakers fall here often.

| Awkward double-keigo | Correct form | Why |

| --- | --- | --- |

| お伺いさせていただきます | 伺います | "Ukagau" is already humble; stacking another humble form is NG |

| ご拝見させていただきます | 拝見します | "Haiken" is already humble |

| お見えになられる | お見えになる | "O-mie" + "narareru" double-respectful |

| ご覧になられる | ご覧になる | "Goran" + "narareru" double-respectful |

| ご質問させていただきます | 質問させていただきます / お聞きします | "Goshitsumon" is normally respectful toward the listener |

**Rule**: "sasete itadaku" is a strong humble form. Do not attach it to already-humble verbs like "ukagau / haiken suru / moushiageru."

16. Direct-Translation Traps: Iken / Goiken / Okangae

| --- | --- | --- | --- |

**Tip**: in English we use imperatives ("please reply"); in Japanese we soften with question or conditional forms like "itadakemasu deshou ka" / "itadakemasu to saiwai desu."

17. English-to-Japanese IT Term Mapping

| English | Japanese | Note |

| --- | --- | --- |

| Pull Request | プルリクエスト / PR | "Pururiku" is common short form |

| Code Review | コードレビュー / レビュー | "Rebyuu" short form is common |

| Merge | マージ | (As-is) |

| Commit | コミット | (As-is) |

| Push | プッシュ | (As-is) |

| Pull | プル | (As-is) |

| Branch | ブランチ | (As-is) |

| Stash | スタッシュ | (As-is) |

| Rebase | リベース | (As-is) |

| Revert | リバート | (As-is) |

| Squash | スカッシュ | (As-is) |

| Cherry-pick | チェリーピック | (As-is) |

| Conflict | コンフリクト | (As-is) |

| Hotfix | ホットフィックス / 緊急修正 | Both used |

| Deploy | デプロイ / リリース | "Depuroi" more common |

| Rollback | ロールバック / 切り戻し | JTC uses "kirimodoshi" |

| Bug | バグ / 不具合 | Both used |

| Feature | 機能 / フィーチャー | "Kinou" more common |

| Spec | 仕様 / スペック | "Shiyou" more common |

| Test | テスト | (As-is) |

| Mock | モック | (As-is) |

| Stub | スタブ | (As-is) |

| Endpoint | エンドポイント | (As-is) |

| Latency | レイテンシ | (As-is) |

| Throughput | スループット | (As-is) |

| Scalability | スケーラビリティ | (As-is) |

18. Emoji and Stamp Culture

In Japanese-company Slack and Chatwork, emoji and stamp use is not decorative — it is a core piece of business communication.

| Emoji/Stamp | Meaning | When to Use |

| --- | --- | --- |

| `:eyes:` | I am looking at it | Acknowledged a message |

| `:white_check_mark:` | OK / confirmed | Task done |

| `:thinking_face:` | Thinking | Working on an answer |

| `:bow:` | Sorry / please | Apology or request |

| `:pray:` | Please / thanks | Universal |

| `:rocket:` | Deployed! / great! | Merge or release |

| `:fire:` | Outage / urgent | #incident channel |

| ありがとうスタンプ | Thank-you stamp | Even for small help |

| OKスタンプ | OK stamp | Quick confirmation reply |

**Tip**: at Mercari and LINE, a senior can reply to a junior's message with just a thank-you stamp and that is taken as a polite enough response. At JTC firms a text reply is still the baseline.

19. Email Formality Mastery: External vs Internal

[External customer email - formal]

株式会社XXX

田中様

いつもお世話になっております。

株式会社YYYの金です。

決済システムv2の件、添付の通り設計書を共有いたします。

ご確認のほど、よろしくお願いいたします。

ご不明な点がございましたら、お気軽にお問い合わせください。

何卒よろしくお願い申し上げます。

金 영주 (Kim Youngju)

株式会社YYY バックエンドエンジニア

youngju@yyy.co.jp

[Internal Slack to colleague - casual]

@田中 v2の設計書できました!

↓ docs/design-v2.md

時間ある時に見てもらえると嬉しいです

お願いします!

**Email vocabulary**:

| Expression | Romaji | When to Use |

| --- | --- | --- |

| いつもお世話になっております | itsumo osewa ni natte orimasu | Email opener (external) |

| お疲れさまです | otsukaresama desu | Email opener (internal) |

| 早速ですが | sassoku desu ga | Jumping into the topic |

| ご連絡いたします | gorenraku itashimasu | I am reaching out |

| ご報告いたします | gohoukoku itashimasu | I am reporting |

| ご相談いたします | gosoudan itashimasu | I am consulting |

| 取り急ぎご連絡まで | toriisogi gorenraku made | Just a quick update |

| 引き続きよろしくお願いいたします | hikitsuzuki yoroshiku onegai itashimasu | Continue to count on you |

20. Soft Refusal and Disagreement

A direct "no" is almost never used in Japanese business culture. Soft refusal phrases are essential.

| Expression | Romaji | Real meaning |

| --- | --- | --- |

| 難しいと思います | muzukashii to omoimasu | I think it is difficult (soft no) |

| 検討させていただきます | kentou sasete itadakimasu | We will consider (probably not happening) |

| 持ち帰らせてください | mochikaerasete kudasai | Let me take this back (cannot decide now) |

| 一度社内で確認します | ichido shanai de kakunin shimasu | Let me check internally |

| お気持ちはわかりますが | okimochi wa wakarimasu ga | I understand your feelings, but (intro to disagreement) |

| おっしゃる通りですが | ossharu toori desu ga | As you say, but (intro to a counter) |

| 別案ですが | betsuan desu ga | As an alternative |

| 別のアプローチとして | betsu no apuroochi toshite | As a different approach |

**Tip for non-Japanese engineers**: "kentou shimasu" in a Japanese meeting is 90% rejection. Translating "this is hard given the schedule" directly as "schedule-teki ni muri desu" is too strong. "Schedule-teki ni kanari muzukashii joukyou desu" lands more naturally.

21. The Apology Ladder

| --- | --- | --- | --- |

**Tip**: "sumimasen" doubles as apology, thanks, and a way to flag attention. It is not strong enough for a real business apology — default to "moushiwake gozaimasen."

22. Time Expressions: Kigen, Shimekiri, Deadline

| --- | --- | --- | --- |

23. Joining and Leaving: Naitei, Nyuusha, Taishoku, Enman Taisha

| Expression | Romaji | Meaning |

| --- | --- | --- |

| 内定 | naitei | Informal job offer |

| オファー | ofaa | Offer (loanword, modern companies) |

| 入社 | nyuusha | Joining the company |

| 着任 | chakunin | Taking up a post (senior/manager) |

| 配属 | haizoku | Assignment |

| 異動 | idou | (Internal) transfer |

| 出向 | shukkou | Secondment (sent to affiliate) |

| 転職 | tenshoku | Job change |

| 退職 | taishoku | Resignation |

| 退職届 | taishokutodoke | Resignation letter |

| 引き継ぎ | hikitsugi | Handover |

| 送別会 | soubetsukai | Farewell party |

| 円満退社 | enman taisha | Amicable resignation |

| 飛ぶ / バックレ | tobu / bakkure | Ghosting (NG) |

**Tip**: Japan expects 1-3 months of notice before resignation. The Korean style of "I am out next week" causes serious friction. Securing enough "hikitsugi kikan" (handover period) is critical.

24. Learning Roadmap: How to Grow Your Japanese IT Vocabulary

[3-month roadmap]

Month 1: Greetings and politeness ladder

- Master otsukaresama desu / shouchi shimashita

- Establish Slack/Chatwork formal register

- Write one gijiroku per week (even for English meetings)

Month 2: Code review and PRs in Japanese

- Write PR descriptions in Japanese

- Try Japanese in review comments

- Switch LGTM to kakunin shimashita

Month 3: Meeting facilitation and 1on1

- Try hosting asakai in Japanese

- Push 1on1 Japanese ratio to 50%

- Host a furikaeri session

Recommended learning resources:

| Resource | Use | URL |

| --- | --- | --- |

| jisho.org | EN-JP dictionary | jisho.org |

| Qiita | Japanese developer posts | qiita.com |

| Zenn | Modern Japanese dev posts | zenn.dev |

| Mercari Engineering | Mercari engineering blog | engineering.mercari.com |

| LINE Engineering | LINE engineering | engineering.linecorp.com |

| DeNA Engineering | DeNA engineering | engineering.dena.com |

| Classmethod DevelopersIO | AWS and tech Japanese | dev.classmethod.jp |

| Recruit Tech Blog | Recruit tech blog | techblog.recruit.co.jp |

References

- [jisho.org - EN-JP / JP-EN dictionary](https://jisho.org)

- [Qiita - largest Japanese dev community](https://qiita.com/popular-tags)

- [Zenn - modern Japanese dev platform](https://zenn.dev)

- [Mercari Engineering Blog](https://engineering.mercari.com)

- [LINE Engineering Blog](https://engineering.linecorp.com/en/blog)

- [DeNA Engineering](https://engineering.dena.com)

- [Classmethod DevelopersIO](https://dev.classmethod.jp)

- [Recruit Tech Blog](https://techblog.recruit.co.jp)

- [News Google Japan - Tech](https://news.google.co.jp)

- [The Japan Times - Tech section](https://www.japantimes.co.jp)

- [CyberAgent Developers Blog](https://developers.cyberagent.co.jp)

- [Yahoo! JAPAN Tech Blog](https://techblog.yahoo.co.jp)

- [GMO Tech Blog](https://recruit.gmo.jp/engineer/jisedai)

- [ZOZO Tech Blog](https://techblog.zozo.com)