Backend Engineer / Distributed Database・Messaging Service / LINE Platform

Position Outline

We are looking for engineers to design, build, and maintain a large-scale, distributed backend for LINE Messaging while focusing on distributed databases engineering under high volume of data and traffic.

Job Details

This role involves developing high-performance data-intensive backend services, optimizing distributed databases usage, and ensuring system reliability. 

LINE Messaging deals with tens of billions of messages exchanged everyday. This is possible thanks to the usage of thousands of servers running distributed storages such as Redis or Apache HBase.
Due to the large scale of services we handle, we face unique, challenging and interesting problems that no one else in the world has encountered yet.

We are seeking for engineers who would like to solve these kind of challenging problems while collaborating with  other backend engineers and SRE, to help develop new features and enhance data consistency, scalability, and fault tolerance across our Messaging Platform.

Some of our tech talks:

• Traffic intensive storages at LINE's Messaging Application
  • https://linedevday.linecorp.com/2020/en/sessions/6595/
• LINE Messaging Platform におけるHBaseとKafkaのデータパイプラインと活用例
  • https://linedevday.linecorp.com/2021/ja/sessions/166/
• LINEアプリにおけるスケーラブルなマルチデータセンター IDジェネレーター
  • https://linedevday.linecorp.com/2021/ja/sessions/163/

Mission/Goals

• Develop and support storage critical features for messaging and related services.
• Provide a reliable, flexible, scalable and secure storage solution for the platform adopting best practices.
• Research and integrate the next storage generation for the future of the platform such as Distributed SQL like TiDB and YugabyteDB.

Responsibilities

• Develop and maintain backend services for a high-scale and traffic intensive Messaging Platform.
• Design and optimize solutions over distributed databases.
• Ensure high availability, consistency, and disaster recovery strategies.
• Monitor and troubleshoot distributed database performance issues.
• Collaborate with cross-functional teams to improve system architecture.
• Maintain and improve observability to support the prevention, early detection, and root cause analysis of system outages.
• Promote automation and efficiency of the above distributed storage middleware operations deployment and management through tools and container orchestration.
• Research and integrate the next storage generation for the future of the platform such as Distributed SQL like TiDB and YugabyteDB.

Responsible Service

• LINE Messaging , Social Graph and their related services.
• LYP Premium.
• LY Federation Platform for ID federation with Yahoo and other groups' ID.

Ideal Candidate

• Individuals who are interested in solving challenging distributed databases problems or distributed systems in general.
• Individuals who are eager to collaborate with other teams within a service in order to identify challenges and devise solutions.
• Individuals who are eager to learn new technologies and can find practical solutions according to team circumstances and schedules, and who can carry out tasks effectively.

Required Experience/Skills

• Major in Computer Science or related fields, or equivalent work experience
• Familiarity with development and system operation in Linux / Unix environment
• Ability to resolve problems in highly concurrent scenarios and distributed architectures.
• Strong interest in distributed storage middleware such as Apache HBase or Redis.
• Attitude to find and solve problems autonomously.
• Communication ability in spoken Japanese and written English.

Preferred Experience/Skills

• Experience in developing and operating a distributed system that handles large amounts of data / large-scale traffic.
• Experience in developing concurrent / multi-threaded systems.
• Development experience related to internal database implementation such as RDBMS or KV storages.
• Ability to develop without problems in JVM-based languages such as Java or Kotlin.
• SRE practices: e.g. Observability, SLO, Error Budget, Infrastructure as Code, Release Engineering.
• Knowledge and experience with observability tools such as ELK Stack, Prometheus, Grafana, etc...
• Experience of operating a large-scale server group using provisioning tools such as Ansible or container orchestration.
• Experience responding to service incidents.
• Motivated to learn Japanese and English language.

Development Environment

• Storage (RDBMS, NoSQL, Event Store): Redis, Apache HBase, Apache Kafka.
• Product and Service Development: Java, Kotlin, Spring Framework.
• Observability: Prometheus, Grafana, AlertManager, Elasticsearch, Kibana, Zipkin.
• Infrastructure: Container (Kubernetes), VM/PM on Private Cloud (Verda).
• Infrastructure as Code, CI/CD, Configuration repository: Ansible, ArgoCD, Jenkins, GitHub Actions.

Salary

Expected annual salary: JPY 6,000,000 to JPY 18,000,000
Form of salary: Monthly salary (including fixed overtime allowance)
Standard monthly salary: JPY 400,000 to JPY 1,200,000
(Breakdown of standard salary)
　―Base salary: JPY 309,000 to JPY 934,000
　―Fixed overtime allowance: JPY 90,000 to JPY 267,000

Fixed overtime allowance of 35 hours will be provided, regardless of whether overtime work is performed.
　Note 1: Overtime allowance is paid separately for overtime work in excess of the fixed 35 hours.
　Note 2: Names of items related to monthly salary vary depending on the grades.
　Bonuses are granted a maximum of two times a year. The amount is determined by factors including the company's and your department's performance.

Type and Period of Employment

• Type of employment: permanent employee　
  
  • Note: No fixed period of employment

Selection Process

• Application
• Coding test/Assignment
• Interviews/ Background Check
• Offer

You will be notified of the results of the selection process within two weeks at the e-mail address you entered in the application form, regardless of whether your application is accepted or not. It may take about one week longer if the application period falls during the Golden Week and the New Year holidays.

Interview, aptitude test, technical test, compliance check/reference check

Applicants who pass the document screening will be required to undergo multiple interviews, aptitude/technical tests, compliance checks, and reference checks, although the details vary depending on the position.

You will be notified of the results of the selection process within two weeks at the e-mail address you entered in the application form, regardless of whether your application is accepted or not.

The schedule will vary depending on interviews and other factors, but if everything goes smoothly, an internal offer will be made within about four to six weeks after the application is submitted. 

Please note that we will not respond to inquiries regarding the details or criteria of the selection process or the reasons for the results, regardless of the results of your application.

Other

To assess your eligibility for the position, we kindly ask you to provide the necessary personal information on the application form. Please note that this information will only be used for recruitment purposes. Please also note that your resume or other submitted documents will not be returned.

Allowances

Overtime allowance, commuting allowance, *1 LY Corporation Working Style allowance,*2 etc.

*1 You will be paid for the number of days you actually came to the office. (Maximum of JPY150,000/month)
*2 Allowance to improve your remote work environment (JPY11,000/month)

Work Location

Head office: Chiyoda-ku, Tokyo, Japan
Offices: Tokyo (Kioicho)The offices are wheelchair accessible.
Note on measures against passive smoking: In principle, no smoking indoors (smoking rooms are available).
Subject to change to an office as determined by the company.

Work Hours

Flextime system: standard work hours 7 hours 45 minutes (no core hours)
Start and end times are up to the individual. However, the company's standard working hours are from 9:30 a.m. to 6:15 p.m.
Note: Some departments may operate on the standard work hours (9:30 a.m. - 6:15 p.m.), while others may have a shift schedule.

Holidays and Leave

Days Off

Two days off per week (Saturdays and Sundays*1), national holidays, New Year's holiday (December 29 to January 4)

Leave

Other

Benefits