Mid or Higher - Full Stack Engineer

About Us

KATIX is a fast-growing auction platform built for transparency and trust. We connect sellers of high value items to bidders. We only allow companies and businesses to participate as bidders. We've started with motorcycles and cars and ours is a modern digital marketplace, and we're expanding. Our focus is on expansion but we'll likely tackle another industry unrelated to vehicles in the near future, and we're building the team that will take us there.

We're a diverse, product-focused team of about 60 people, with an average age of 27 and over 50% women. We care about building great software, we care about the people who build it, and we care about having fun while we do it.

KATIX is a fast-growing auction platform built for transparency and trust. We connect sellers of high value items to bidders. We only allow companies and businesses to participate as bidders. We've started with motorcycles and cars and ours is a modern digital marketplace, and we're expanding. Our focus is on expansion but we'll likely tackle another industry unrelated to vehicles in the near future, and we're building the team that will take us there.

We're a diverse, product-focused team of about 60 people, with an average age of 27 and over 50% women. We care about building great software, we care about the people who build it, and we care about having fun while we do it.

We're looking for a full stack engineer with strong web engineering foundations to join our engineering team. You'll work on a modern TypeScript/Next.js monolith used by thousands of users every day, and you'll contribute across the stack, from buyer flows and auction tooling to internal dashboards and infrastructure.

This is not a role where you'll wait for tickets. We expect engineers at this level to bring ideas, push back when something isn't right, and take real ownership of what they build. Over time, there's a clear path toward tech lead and senior engineering roles as we scale.

We're looking for someone who has genuinely looked into KATIX, understands what we're building, and wants to be part of it. If you believe in what we're doing and want to grow with us, we want to hear from you.

What You'll Work On

Our main product is a vehicle sales platform, auctions, escrow, AI integrations, user onboarding, and internal tooling, built as a large TypeScript/Next.js monolith. You'll work deep inside this codebase, contributing across:

Frontend features using Next.js (App Router) and TypeScript

Backend logic via API routes, server actions, and shared packages

System design, database schema, and feature planning

AWS infrastructure, Docker, ECS, and GitHub Actions deployments

Code review, testing, and CI pipeline reliability

Team planning, standups, and retrospectives

What We're Looking For

Required

5 or more years of professional web engineering experience

Strong full-stack background, comfortable with both frontend and backend work

Solid understanding of web architecture, system design, and data modeling

Experience with modern web frameworks (React, Vue, or similar)

Exposure to backend development, API design, and relational databases

Experience with cloud infrastructure, AWS, Docker, or similar

Experience mentoring others or leading small projects

Comfortable working in a Scrum or Agile team

Conversational Japanese (you'll be working with a Japanese-speaking team, outside of engineering everyone speaks Japanese, product, corporate, sales. You may speak English day to day but you'll need to speak enough Japanese to communicate with non-engineers.)

You'll ship real features from day one, no backlog purgatory

You'll work in a clean, modern codebase with a collaborative team that actively mentors and reviews

Clear growth path into tech lead and senior engineering roles

Help shape how we build software as we scale toward our next phase of growth

A diverse, friendly team with a strong product culture

Benefits

Transparent compensation table with performance reviews every 6 months

Two annual performance bonuses

Housing allowance for those living near Shibuya

Dedicated budget for learning, certifications, and study

One or more remote work days per week (after the first 6 months)

How to Apply

You don't need a perfect resume or a portfolio full of side projects. What we do want to see is that you've looked into KATIX, that you understand what we're building, and that you're genuinely excited about being part of it.

Tell us about yourself, what you've built, and why KATIX. We'd love to hear from you.

Before Applying, Ask Yourself

How confident am I in building anything I'm tasked with (given I have the right resources)?

Why do I want to apply to KATIX?

If you can confidently say you can build anything and you're reasons for applying to KATIX are specific to KATIX, then please apply.

But if you're reasons for applying to KATIX are the same for applying for any other company then don't bother. For example if you want "to grow as an engineer" you can grow as an engineer at any company (including KATIX) we're looking for people who want to join us for more concrete reasons specific to KATIX.