We are looking for a Senior Software Engineer to take ownership of backend and web-platform development for HENNGE One, our flagship cloud-security suite serving over 2.8 million users globally. As a B2B SaaS leader in Japan, we provide mission-critical security solutions that empower enterprises to work safely from anywhere.
In this role, you will join the Email Data Loss Prevention (DLP) Team, responsible for the development of HENNGE One DLP Edition. You will be developing our core data protection engine—the technical backbone of our outbound security ecosystem. Your work ensures secure and compliant communication for millions of users by preventing information leakage through high-impact features like real-time email missending filters and automated secure file transmission. This position is ideal for engineers who thrive on building fault-tolerant, event-driven architectures and managing high-throughput data processing within a mission-critical security environment.
While this role primarily focuses on the DLP Edition, we value engineers who are flexible and open to new challenges, with opportunities to move between teams and products through two-way discussions that support your growth and the company’s goals.
Tech Stack: Go, AWS (SQS/SNS, DynamoDB, PostgreSQL, OpenSearch), Terraform
Responsibilities
- Design, build, and maintain new features for HENNGE One, using Go and other web technologies.
- Architect scalable, fault-tolerant services deployed in cloud environments.
- Automate deployment, testing, monitoring and documentation via CI/CD pipelines and infrastructure-as-code.
- Collaborate closely with Product Management, Design, and Customer Success teams to deliver high-quality user experiences.
- Participate actively in code reviews, discussions and technical decision-making.
- Mentor junior engineers, and contribute to improving team processes and engineering culture.
Requirements
- 3+ years of experience developing production-scale backend services using Go.
- Ability to lead technical initiatives, mentor junior engineers, and work collaboratively in a team environment.
- Hands-on experience with cloud infrastructure (AWS) and distributed system concepts (event-driven architectures, high-throughput data flows).
- Experience with CI/CD, automated testing, code documentation, and clean-code practices.
- Fluency in English (Japanese is not required), equivalent to CEFR B2 level or above (e.g., TOEIC 785+).
- Interest in contributing to open-source projects or participating in the tech community.
Nice to haves
While not specifically required, tell us if you have any of the following.
- Degree in Computer Science or other related technical fields.
- Experience building large-scale distributed systems or SaaS products in the B2B space.
- Experience with email security, secure file transmission, or cloud security products.
- Knowledge of DevOps tools and practices (Terraform, Infrastructure as Code).
- Knowledge of Linux / MacOS / Unix-like environments.
- Certification in AWS (Solutions Architect, Developer, etc.).
- Team leadership experience.
Compensation
¥8,500,000 ~ ¥12,500,000 annually.
Our salary range is inclusive of English Allowance & Physical Communication Bonus - please check the details below, with the final amount determined based on your experience and skills.
Please refer to our Company Introduction Deck for an explanation of our Assessment System and the Belt System, which we use to determine the candidate’s salary range.
Benefits
- English Allowance and Advanced Language Expert Allowance: JPY 10,000 ~ JPY 130,000 per month, paid alongside base salary, if the employee fulfills the requirements.
- Physical Communication Bonus: JPY 4,000 per day, applicable from October 2025 onwards, for coming to the office and interacting with other employees, paid out as bonus according to the number of days.
Details will be provided at the offer meeting.
