Application Security Engineer / Security Center

TokyoLINE CorpEngineeringSecurity Engineering, BlockchainFull-time


Ensure the security and quality of a wide range services and products developed by LINE and group companies.
Platforms and technologies include Web, mobile, desktop, IoT, Fintech, and more.

Major Responsibilities

  • security consulting at the planning and design stage
  • security testing and risk assessment
  • abuse analysis and prevention
  • LINE Security Bug Bounty operation

LINE Application Security Team Profile

  • We strive to perform most security tasks in-house, and employ security engineers full-time.
  • Security engineers get full access to source code, and can communicate directly with developers and product owners.
  • Security engineers are free to choose and build their tools: we employ both open source, commercial, and in-house security tools
    and solutions.
  • We value speed, efficiency, and direct communication. High-overhead risk and vulnerability reporting is generally unnecessary.
  • We support and encourage OSS contributions, CTF participation, journal publishing and conference participations in the fields of computer security and science.

Preferred Qualifications

  • software engineering experience
  • contributions to OSS projects, especially related to security
  • high-profile CTF participation
  • presentations and publications in the fields of computer security

*Experience in of the following

  • design, development, or security review of large-scale software systems
  • security testing and vulnerability reporting for Web, mobile, or IoT applications/devices
  • large-scale log analysis and pattern/anomaly detection

*An edge to have

  • Fintech or blockchain-related development or security testing experience

*Language Skills

Ability to communicate in English or Japanese. Bilinguals welcome.

Working Hours

One of the followings will be applied: Discretionary labor system for professional work (Employee is deemed to have worked for 9.5 hours a day, regardless of the actual number of hours worked), Flex-time system (core time: 11:00 am–4:00 pm) or 10:00 am–6:30 pm(actual working hours 7 hr 30 min)
*To be determined after the interview process


Weekends (Saturdays and Sundays), national holidays, paid leave, New Year’s holiday, congratulatory and condolence leave, "Refreshment" leave (every 5 years, employees who have been employed under a continuous contract are entitled to 10 days of paid leave)


Annual salary system (To be determined based on skills, experiences and abilities after discussions)

  • Annual compensation will be divided into 12 months and paid on a monthly basis.
  • Separate incentives available (*1)
  • Compensation revision: twice a year
  • Allowances: commuting allowance, LINE Pay Card Benefit Plan (*2)
    (*1) In addition to your annual compensation, you may receive incentives (twice a year) depending on the company's and individual performance and evaluation on your performance. (Incentives are not guaranteed to be provided. An incentive payment will only be paid if you remain employed as of the payment date.
    (*2) This is an allowance separate from the salary meant for employees to use for their health, personal development, support for raising the next generation, and more.


  • Employment insurance, workers accident compensation insurance, health insurance, employees pension insurance


  • Periodic health checkup
  • Company events and others



*Implementation of second-hand smoke prevention measures

[Prohibiting Indoor Smoking (other than Smoking Room)]
Shinjukul, Osaki, Minami-shinjuku, Yotsuya
[Prohibiting Indoor Smoking (outdoor Smoking Area)]
Shinuku (NEX), Nishi-shinjuku



Details to be shared during interviews.

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