Tokyo, Japan

We build software
and the teams
that ship it.

A3 Tech Group is a Tokyo-based engineering studio. We deliver production full-stack systems, applied AI, and the kind of hands-on AI training that turns a team into a capable one.

Contact usWhat we do
10+ yrs
combined senior delivery
Full-stack
web · mobile · cloud · AI
Worldwide
remote-friendly delivery
Trusted across
  • Fintech
  • SaaS
  • E-commerce
  • Healthcare
  • Manufacturing
  • EdTech

01 — Services

What we do, and do well.

One senior team across the whole lifecycle — from a blank repository to a system your engineers can own and your business can grow on.

01

Full-Stack Development

End-to-end product engineering: clean APIs, considered front-ends, and infrastructure that doesn't wake you at 3 a.m. We write code your team will still understand a year from now.

  • Web apps
  • APIs
  • Cloud
  • DevOps
02

Applied AI & LLM Systems

RAG pipelines, agents, and model integrations built for the real world — evaluated, observable, and safe to put in front of customers. AI that earns its place in the product.

  • RAG
  • Agents
  • Fine-tuning
  • Evals
03

AI Training for Teams

Practical, hands-on programs that take your engineers from curious to confident — prompt engineering, building with LLMs, and shipping AI features responsibly. Taught by people who ship daily.

  • Workshops
  • Mentoring
  • Curriculum
04

Architecture & Consulting

Technical due diligence, system design reviews, and a second set of senior eyes when the stakes are high. Honest assessments, not billable theatre.

  • Audits
  • System design
  • Scaling

02 — Approach

Craft over noise.

We believe in steady, deliberate improvement — applied to how software gets made. Small steps, shipped often. Nothing goes out that we wouldn't run ourselves.

  1. I

    Listen first

    We start with your constraints and your customers — not our favourite framework. The right tool is the one your team can live with.

  2. II

    Build in the open

    Short cycles, visible progress, working software early. You see decisions as they happen, never a black box.

  3. III

    Leave it better

    We hand over documented, tested systems — and the knowledge to run them. Our goal is to make ourselves optional.

03 — Stack

The tools we reach for.

Pragmatic, proven, and chosen per project — never cargo-culted.

Frontend

  • React
  • Next.js
  • TypeScript
  • Vue
  • Tailwind

Backend

  • Node.js
  • Go
  • Python
  • PostgreSQL
  • GraphQL

AI / ML

  • Claude & OpenAI
  • LangChain
  • PyTorch
  • Vector DBs
  • RAG

Cloud & Ops

  • AWS
  • GCP
  • Docker
  • Kubernetes
  • Terraform

04 — Leadership

Daniel — Hiro Tanaka

Chief Technology Officer

Daniel leads engineering at A3 Tech Group. He has spent his career at the intersection of solid software and applied AI — architecting systems, mentoring engineers, and keeping delivery honest. He believes good technology is quiet: it works, it lasts, and it gets out of the way.

“We don't sell complexity. We sell software that holds up — and teams that can carry it forward without us.”
Talk with Daniel

05 — Contact

Let's build something that lasts.

Tell us what you're working on, or book a 30-minute call — no slide deck, just a straight conversation.

Send us a message

We reply to every enquiry within one business day.

By sending this you agree to be contacted about your enquiry. We never share your details.

  • LocationTokyo, Japan
  • ResponseWithin 1 business day
  • LanguagesEnglish / 日本語

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