Legacy modernization and AI for Japanese companies, with a documented, predictable process.
A software engineer for Japanese companies, working remotely from Mumbai with my morning in your afternoon. It is for teams modernizing legacy systems and adding AI that want detailed plans, documentation and a predictable process.
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What teams in Japan bring me
A core system is old and hard to change, but it cannot stop, so you need a migration plan in clear phases rather than a risky rewrite.
You want AI features, documented: how they are evaluated, what they cost to run, and what happens when they are wrong.
You need a detailed quotation and specification before any work starts.
02
Working with teams in Tokyo
Japan is three and a half hours ahead: my morning is your afternoon. I plan around Golden Week, Obon and the New Year holidays, and report progress in writing on a fixed rhythm, so nothing depends on a call.
Each city's 09:00–18:00 working day on the clock in Mumbai (UTC+5:30), in January and in July, so daylight saving is accounted for.
| City | In January | In July |
|---|---|---|
| TokyoUTC+9 | 05:30–14:30 | The same |
The rules that apply here: Act on the Protection of Personal Information (APPI) · The APPI amendment of 2026 · The AI Promotion Act
03
Contracts and invoicing in Japan
Invoices in yen or US dollars, per milestone, paid through Wise or Payoneer. A detailed quotation and specification come before work starts, and I sign your non-disclosure agreement as standard.
Tax and legal treatment depends on your company and country: confirm it with your accountant or counsel.
04
Data protection and the rules that apply
Act on the Protection of Personal Information (APPI)
Supervised by the Personal Information Protection Commission. The engineering: purpose limitation, security controls, and the rules for providing personal data to third parties, including overseas.
Source: Personal Information Protection Commission: laws and policies
The APPI amendment of 2026
A bill amending the APPI, submitted to the Diet on 7 April 2026, was passed on 10 July 2026 and promulgated on 17 July 2026. The Commission adopted a roadmap for implementing it on 31 July 2026 and, on 26 August 2026, an overview of the matters to be set by cabinet order and Commission rules; those orders, rules and guidelines are still being prepared. Until they are published, I design so changes like these are cheap to absorb.
Source: Personal Information Protection Commission: the 2026 amended APPI (令和8年 改正個人情報保護法)
The AI Promotion Act
Japan's Act on the Promotion of Research, Development and Utilisation of AI-Related Technologies (Act No. 53 of 2025) was promulgated and partly brought into force on 4 June 2025, and has been fully in force since 1 September 2025, including the provisions setting up the AI Strategy Headquarters.
Source: Cabinet Office: the AI Act (人工知能関連技術の研究開発及び活用の推進に関する法律)
This is engineering guidance, not legal advice: confirm what applies to your business with your counsel.
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Where teams in Japan usually start
Legacy modernization
Move an aging system to a modern stack without stopping the business.
- Price
- Fixed-price assessment, then a fixed quote per stage
- Timeline
- An assessment first, then migration in stages on a schedule agreed with you
AI features in your product
LLM features that work on your real data, measured before they ship.
- Price
- Fixed-price scoping sprint, then a fixed-scope quote
- Timeline
- A scoping sprint first, then a timeline agreed per project
Architecture review and due diligence
An independent, written view of a system: what's solid, what's risky, and what it will cost to fix.
- Price
- Fixed price per scope
- Timeline
- Agreed per project after scoping
Performance and Core Web Vitals audit
Find out in five working days exactly why your application is slow, and what to fix first.
- Price
- Fixed price
- Timeline
- Agreed per project
06
Case studies behind this work
- Case study: TopGear India CMS · CMS migration and modernization
- page load time, before → after
- 1–3 min → 3 s
- Case study: Zyrobe · AI wardrobe app
- average time per image, upload to result
- 3–8 s
- Case study: Vayudoot Aviations · Education platform
07
Questions from teams in Japan
Can you provide a detailed estimate before we start?
Yes. Every engagement starts with a fixed-price scoping step that ends in a written plan: phases, deliverables, risks and costs.
Do you work in Japanese?
I work in English. Specifications and reports can be prepared for translation, and I work well with a bilingual project lead on your side.
How do you report progress?
In writing, on a fixed rhythm: what was done, what comes next, and any risk that needs your decision.
What does APPI mean for a web app?
The Act on the Protection of Personal Information is supervised by the Personal Information Protection Commission. For a web app the engineering comes down to purpose limitation, security controls, and the rules for providing personal data to third parties, including overseas. An amendment was passed on 10 July 2026 and promulgated on 17 July 2026, and its orders and guidelines are still being prepared, so I design so that changes like these are cheap to absorb. Your counsel confirms what applies; the guide to working with an engineer in India covers how personal data may reach someone outside your country.
How do you work with Japanese documentation and process expectations?
In writing and in order. A detailed quotation and specification come before work starts, every engagement begins with a fixed-price scoping step that ends in a written plan, and I sign your non-disclosure agreement as standard. Progress is reported in writing on a fixed rhythm, and I plan around Golden Week, Obon and the New Year holidays, so nothing depends on a call.
Can you modernize a legacy system without stopping it?
Yes, in stages: a written assessment says what to keep, rewrite and retire, then old and new run side by side, one area moves at a time and each step can be reversed. Legacy modernization is the offer, and the staged migration playbook shows the method on a magazine CMS that kept publishing every day.
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Related writing
- Article: Is llms.txt worth it in 2026? What Google, OpenAI, Anthropic and Perplexity document · 2 November 2026
What the llms.txt proposal is, what each company’s own documentation says about it, what Ahrefs’ crawl of 137,210 domains found, and what to do instead.
- Article: What a penetration test report contains · 2 November 2026
The sections of a web application pentest report, what each one is for, and a fictional sample finding written the way I write real ones.