Backend Engineer

Application Guidelines

Job Description
  • The following duties are in relation to Gehirn Web Services, a service provided by the company.
    • Research, verification and selection of technical standards and middleware to be used
    • Architectural design throughout the service
    • Implementation of back-end applications
    • Operation of the developed services
    • Investigate and correct any bugs or defects found in our services and open source software
  • Development and operation of the operational infrastructure for monitoring, customer management and data analysis of our services
  • Development and operation of internal tools
Application Requirements
  • Extensive experience of application programming in one or more of the following languages
  • Ability to read and understand RFCs and other technical documents written in English and implement them correctly using the above programming languages.
  • Knowledge and experience with databases, including
    • Knowledge of the relational model, including candidate keys, foreign keys and function dependencies
    • Knowledge of data integrity, including ACID properties, transaction isolation levels and Eventually Consistent
    • Knowledge and experience of data structure-aware physical design of RDBMSs and performance tuning through the use of secondary indexes
    • Knowledge of data model design in schema-less databases
  • Knowledge of basic security vulnerabilities and how to address them, including
    • XSS / CSRF / Header Injection and other Web / HTTP vulnerabilities
    • Input value handling vulnerabilities such as SQL injection and OS command injection
    • Buffer overrun and other memory management vulnerabilities
    • PKI vulnerabilities such as X.509 certificate validation flaws
  • Experience in operating services using Linux (mainly Ubuntu Server)
Welcome Skills and Experience
  • Skills and experience in designing and implementing RPC interfaces such as gRPC and Apache Thrift
  • Skills and experience in application integration via message bus (e.g. RabbitMQ or Kafka)
  • Skills and experience in designing applications that use managed services such as those provided by Google Cloud Platform and Amazon Web Services
  • Skills and experience in running containerised applications using Docker, Kubernetes etc.
  • In-depth knowledge of identity, authentication and authorisation
  • In-depth knowledge of virtualisation technologies using KVM/QEMU
  • System programming skills and experience in the Linux kernel
  • Skills and experience in server provisioning using Ansible, Chef etc.

Monthly income from ¥400,000

  • Determined in accordance with our internal policies, taking into account performance and ability.
  • Includes a fixed overtime allowance of 20 hours.
Associated Department
Engineering Division, Research and Development Department
Employment Status
Permanent Staff (3 month evaluation period)
Chiyoda-ku, Tokyo
Work Location
Tokyo HQ (Chiyoda-ku, Tokyo)
※ Remote work available (for residents of Japan)
Working Hours
Flextime system (no core time)
  • Standard working day of 8 hours
  • You may be asked to work at a specified date and time, if you have meetings or work commitments.
Twice yearly (from the second year onwards)
determined by the performance of the previous year.
Time Off
  • 2 days per week (Saturday + Sunday)
  • Public Holidays
  • New Years
  • Paid Leave
  • Special Leave (Congratulatory + Condolence Leave, Birthday Leave)
Social Insurance / Benefits
  • Full Range of Social Benefits
  • Health Checkup (Once yearly)
  • Commuting Allowance (up to 30,000 yen)
  • Moving Allowance (once only, before or after starting your position)
  • Welfare Club (Relo Club)
Language Proficiency
Japanese JLPT N3-N2 equivalent
English skills welcome but not required
Other Conditions
  • Enjoy or participate in conversation about Evangelion and Ghost in the Shell.
  • Enjoy working in the setting of "employees of an undisclosed organization that reports directly to the UN."
  • Willingness to learn new skills and technologies.
  • Enjoy working in (or not dissatisfied with) a nonhierarchical organisation.

Recruitment Process

How to Apply

Send an email to with the following requirements.
A member of our team will respond as soon as possible.

  • The body of the email should be in plain text
  • Include all of the following personal information requirements in the body of the email
  • Include answers to the following questions in the body of the email
  • Encrypt the body of the email using PGP with the public key provided below
Personal Information
  • Applicant's Name
  • Applicant's Email Address
  • Desired PositionRequired
  • Work HistoryRequired
  • MotivationRequired
  • Explain how you can help us to achieve our mission to "Make Japan Safer".Required
  • Link your GitHub account, portfolio, blog, web services you run, or any other links that show your activities. Optional
  • Let us know of any Open Source projects or Web Services that interest you.Optional
  • Let us know of any questions you may have about our company. Optional

Handling of Personal Data

Gehirn Inc. has established the following policy for the safe storage and management of personal information and the use of personal information in accordance with the wishes of applicants for employment.
Recruitment Privacy Policy

When you apply for a job, you must agree that the information you provide will be managed in accordance with our Recruitment Privacy Policy.

If you agree, please tick the 'I agree to the privacy policy' checkbox below, download the PGP public key and submit your application.