Senior Software Engineer – Backend (Python)

Role Snapshot

Location: Tokyo, Japan (Shibuya HQ)

Employment Type: Permanent, Full-Time

Salary Range: ¥8.5M – ¥12.5M + Allowances & Bonus

Language: English Required (Japanese Not Required)

Visa/Relocation: Visa Sponsorship & Relocation Support Available

About the Role

This role focuses on backend and web-platform development for core features including Access

Control, Single Sign-On (SSO), and Secure Browser.

Key Responsibilities

Design, build, and maintain backend services using Python and modern web

technologies.

Architect scalable, fault-tolerant cloud-native systems.

Automate CI/CD pipelines, testing, monitoring, and documentation.

Collaborate cross-functionally with Product, Design, and Customer Success teams.

Participate in technical discussions, architecture decisions, and code reviews.

Mentor junior engineers and contribute to engineering best practices.

Required Qualifications

5+ years of production experience building backend systems using Python.

Experience designing and maintaining production-scale web applications.

Hands-on experience with cloud platforms (AWS preferred; GCP/Azure acceptable).

Strong understanding of distributed systems concepts.

Experience with CI/CD, automated testing, documentation, and clean code practices.

Ability to mentor engineers and collaborate in team environments.

Fluent English (CEFR B2 level or higher).

Preferred Qualifications

Experience building SaaS products or large-scale distributed systems.

Knowledge of web security, access control, or identity management systems.

Experience with DevOps practices and Infrastructure as Code.

Familiarity with Linux / Unix-like environments.

Team leadership experience.

Tech Stack

Python (Tornado, FastAPI)

AWS, DynamoDB, PostgreSQL

CI/CD & Infrastructure-as-Code tools

Work Style & Benefits

Flexible working hours (core time 11:00–16:00).

International, English-speaking engineering environment.

English Allowance (¥10,000–¥130,000 per month based on qualification).

Physical Communication Bonus for in-office attendance.

Transportation allowance (up to ¥35,000 per month).

Employee Stock Ownership Plan.

Conference attendance and certification support.