Senior Product Engineer – Security | AI × Cybersecurity × FinTech

One of our key clients, a fast-growing Japanese technology company specializing in AI, Data, and Digital Transformation, with a strong focus on major financial institutions, is looking for a Senior Product Engineer – Security to join its growing AI & Data business.

In this role, you will design and develop security analysis and diagnostic capabilities for proprietary AI products used by major financial institutions.

You will work at the intersection of Software Engineering, Cybersecurity, and Generative AI, transforming security expertise and vulnerability assessment methodologies into scalable product features using rules, algorithms, Generative AI, and AI Agents.

This is not a traditional internal security operations, SOC, or audit role. It is a hands-on product engineering position where you will build software that analyzes vulnerabilities and security risks, identifies issues across source code, system architecture, libraries, and configurations, and provides actionable insights and improvement recommendations.

The development team consists of approximately 10–15 members.

• This is a Hybrid positon (3 ~ 4 days remote / Week) with Flex Hour
  
• Salary: ¥10,000,000 – ¥25,000,000 / year
  
• International Environment
  

Why Join?

• AI × Cybersecurity: Develop security analysis and diagnostic functionality using Generative AI and AI Agents.
  
• Product Development: Transform security expertise and assessment methodologies into reusable software features.
  
• Major Financial Institutions: Work on products addressing complex security challenges for large financial organizations.
  
• High Technical Ownership: Take part in product design, technical decisions, development strategy, and implementation.
  
• Modern Tech Stack: Work with TypeScript, Python, Node.js, React, Next.js, Google Cloud, and Terraform.
  
• Professional Growth: Support for books, training, Udemy, study sessions, qualifications, and other learning opportunities.
  

Role Overview

As a Senior Product Engineer – Security, you will lead the design and development of security-related capabilities for proprietary AI products targeting major financial institutions.

You will analyze vulnerabilities, security risks, source code, system architecture, libraries, and configuration information and develop software capabilities that identify security issues and potential areas for improvement.

A key part of this role is converting cybersecurity expertise and diagnostic methodologies traditionally held by security specialists into scalable software capabilities using rules, algorithms, AI, Generative AI, and AI Agents.

You will also collaborate closely with customers, security specialists, consultants, Product Managers, and designers to identify problems, validate hypotheses, and translate complex security and business requirements into product functionality.

Key Responsibilities

• Design and develop proprietary AI products for major financial institutions.
  
• Provide technical leadership throughout product development.
  
• Understand security challenges and business requirements from financial institutions and translate them into product requirements.
  
• Plan, design, and develop functionality for analyzing, diagnosing, and visualizing vulnerabilities and security risks.
  
• Analyze source code, system architecture, libraries, configuration information, and other technical assets.
  
• Develop functionality capable of identifying security issues and recommending improvements.
  
• Translate security knowledge and diagnostic methodologies into software using rules, algorithms, and AI.
  
• Enhance security analysis and diagnostic capabilities using Generative AI and AI Agents.
  
• Collaborate with customers, security specialists, consultants, Product Managers, and designers.
  
• Participate in problem discovery and hypothesis validation.
  
• Drive development from implementation through release and quality assurance.
  

Tech Stack

Backend:

TypeScript / Python / Node.js

Web Frontend:
React / Next.js / Tailwind CSS

Infrastructure / CI/CD:
Google Cloud / Terraform / GitHub Actions

AI Development Tools:
Claude Code / Codex

Collaboration:
Slack / Jira / Confluence / GitHub Wiki / Figma

Requirements

Requirements

• 3+ years of professional system/software development experience.
  
• Fundamental knowledge of cybersecurity, including vulnerabilities, security risks, and attack methods.
  
• Ability to understand security challenges and assessment perspectives and translate them into software requirements, design, and implementation.
  
• Ability to drive development end-to-end, from implementation through release and quality assurance, with a focus on business challenges and user experience.
  
• Business-level English sufficient for technical discussions.
  
• Valid status allowing employment as an IT professional in Japan, with the status not expiring within six months after joining the company.
  

Preferred Qualifications

• Professional experience in vulnerability assessment, security assessment, or penetration testing.
  
• Knowledge of or development experience with SAST, DAST, SCA, or other Application Security technologies and products.
  
• Knowledge of or development experience in source code analysis, static analysis, or program analysis.
  
• Knowledge of vulnerability information and evaluation frameworks such as CVE, CWE, and CVSS.
  
• Knowledge of OSS dependencies, SBOM, and Software Supply Chain Security.
  
• Knowledge of Cloud, Network, OS, or Middleware Security.
  
• Experience with Security Products related to vulnerability management, ASM, CSPM, or CNAPP.
  
• Security experience within financial institutions or enterprise environments.
  
• Specialized knowledge in Information Security, Information Engineering, Computer Science, or related areas.
  
• Business-level Japanese communication skills.
  

Ideal Candidate

• A strong software engineer with solid cybersecurity knowledge.
  
• Comfortable remaining hands-on while providing technical leadership.
  
• Able to translate complex security expertise into scalable product functionality.
  
• Comfortable collaborating across engineering, security, consulting, product, and design teams.
  
• Able to operate effectively in an environment with a high degree of uncertainty.
  
• Interested in applying software engineering and AI to high-impact challenges in the financial industry.
  
• Comfortable working in a fast-growing and dynamic organization.
  

Benefits

Salary: ¥10,000,000 – ¥25,000,000 / year

Location: Nihonbashi / Kayabacho, Tokyo

Work Style

• Full-time permanent position.
  
• Hybrid work available.
  
• Full-flex working hours with no core time.
  
• Flexible working hours between 5:00 and 22:00.
  
• Professional discretionary labor system may apply depending on the position.
  
• Standard working time: 8 hours per day with a 1-hour break.
  
• Average overtime: approximately 20–30 hours per month.
  
• 123 annual holidays.
  
• Full two-day weekend system.
  
• Year-end/New Year, refresh, childcare, and special leave available.
  

Benefits

• Social insurance.
  
• Defined contribution pension plan.
  
• Employee stock ownership program.
  
• Support for books and study sessions.
  
• Udemy learning support.
  
• Sports allowance.
  
• Health checkup and vaccination support.
  
• Transportation allowance.
  
• Babysitter support.
  
• Relocation support for eligible employees.