Lead Data Engineer | Osaka or Tokyo / Remote (Flexible) | Multinational Team #274

Company Overview

The company operates a marketing SaaS platform leveraging LINE. As a rapidly growing startup, it utilizes AI technologies to help brands build sustainable and trustworthy relationships with their customers.

In addition to its LINE marketing tools, the company develops and provides a range of services, including LINE 1-to-1 business chat, digital membership card LINE mini apps, and AI-powered call solutions.

■Key Features

• Operates in the C-commerce market, which is estimated to be worth nearly JPY 30 trillion globally and is projected to surpass the e-commerce market in certain countries by 2025
• Achieved 760% business growth over the past three years in the marketing SaaS domain
• Successfully raised a total of JPY 6.3 billion in funding (including JPY 3.5 billion in Series B)
• Ranked No.1 in LINE marketing in Japan
• A global organization with offices overseas and team members representing 20 different nationalities

 

Responsibilities

The Data Platform Team was established in May 2026 as a newly formed team. Its mission is to build sustainable, compounding governance capabilities for the increasingly complex data models of existing products as the business continues to grow rapidly, rather than treating data governance as a one-time cleanup exercise.

The Lead Data Engineer will define the team’s technical direction and roadmap and drive execution. Core responsibilities include prioritizing and defining completion criteria for the governance foundation, establishing decision-making frameworks for data tiering and storage selection, designing an overall strategy to reduce database load, and ultimately leading the next generation of customer and segment data models.

The role also serves as a guardian of engineering discipline within the team. When incidents or delivery pressures arise, the Lead Data Engineer is expected to maintain sound decision-making principles and prevent the team from taking shortcuts such as bypassing established tools and directly refactoring production systems. The role also involves clearly explaining and communicating the rationale behind technical decisions to stakeholders.

This position is one level above the Senior Data Engineer role. The scope expands from individual entities to the overall platform, from implementation within a single quarter to a 12-month technical roadmap, and from individual output to team-wide leverage.

Key Responsibilities

• Maintain and evolve the technical direction and roadmap: Build on the existing 12-month roadmap and update and maintain phase definitions, exit criteria, dependencies, and critical paths on a quarterly basis. Clearly distinguish between firm commitments and areas that remain directional.
• Design and prioritize the governance foundation: Define the minimum viable standards for lineage, test reliability, benchmarking, data classification, decision records, local reproduction environments, and collaboration with external experts. Validate their effectiveness through real-world projects while avoiding both over-engineering and insufficient coverage.
• Establish a decision-making framework for data tiering and storage selection: Based on data classification and lineage, establish a framework for determining which entities should remain in TiDB and which should be moved to Snowflake, ensuring that the framework becomes the default approach for new requirements.
• Lead the next generation of data models: Lead the redesign of customer and segment data models using a profiling-first approach, establishing an evidence chain of classification + lineage + benchmarking → decision → documentation.
• Design the overall strategy for reducing database load: Design the architecture and migration sequence for data deletion based on retention policies, event attribute enrichment, offloading heavy aggregation workloads to Snowflake, and reverse ETL, and drive execution.
• Build consensus with business teams: For changes requiring significant involvement from business teams, such as deleting production data or migrating large-scale segment definitions, explain impacts and risks in language accessible to non-engineers and reach agreement on implementation priorities and sequencing.
• Design and operate frameworks for collaboration with external experts: Establish regular review processes with database and data warehouse vendors, centralize points of contact, define escalation paths, and ensure that key technical decisions are documented.
• Lead and institutionalize major incident response: Take command during major incidents and drive the process through RCA and the implementation of measures to prevent recurrence. Turn every incident into an opportunity to improve the underlying systems and processes.
• Develop and recruit team members: Mentor and develop engineers at Senior level and below, design onboarding processes, and participate in recruitment activities. The scope of people management can be discussed based on the candidate’s career interests and organizational needs.
• Remain hands-on: Personally design and implement solutions in the most technically challenging areas and when launching new systems or processes, setting the team’s technical standards through code.

Expectations for the Role

• Design the governance foundation and data-tiering decision framework and drive implementation by engaging the broader team and relevant departments.
• Maintain the 12-month roadmap, review progress monthly, and deliver meaningful outcomes each quarter, while avoiding assigning premature scope, timelines, or implementation details to areas that are not yet ready for commitment.
• Quantitatively manage database capacity risks, legacy data expiration schedules, and costs, creating a state in which these areas can be clearly explained and reported to management.
• Serve as a guardian of engineering discipline and prevent the team from bypassing established tools and processes to directly refactor systems under pressure.
• Establish a governance capability that remains resilient despite team changes by maintaining data lineage, runbooks, decision records, and other institutional knowledge.

What the Position Offers

• Autonomy to build implementation frameworks on top of established principles: The overall principles have already been established, but many of the details remain open, including completion criteria for the governance foundation, decision frameworks for data tiering, and redesign of core entities. This provides an opportunity to build upon established principles through your own technical judgment.
• Decision-making with a direct impact on product longevity: Decisions about where entities should reside and which data models should be rebuilt will determine when legacy infrastructure can ultimately be retired. This is an opportunity to experience firsthand how technical decisions can expand business options.
• Direct exposure to business and management: Gain experience explaining capacity risks, retention policies, and migration costs in your own words while securing the resources and involvement required from business teams.
• Opportunity to build collaboration frameworks with leading vendor engineers: Design and operate structured, long-term collaboration with database and data warehouse vendors rather than relying on vendors as ad hoc technical support.
• Leadership experience in a global organization: Take technical initiatives within a multinational team where English is used regularly, while leading development and standardization efforts and building leadership experience applicable to global engineering organizations.

Career Development Opportunities

• Data Platform Tech Lead / Engineering Manager: Progress toward managing the broader Data Platform organization based on experience in team leadership and talent development.
• Chief Data Architect / Principal Engineer: Pursue a highly specialized technical career focused on shaping the company-wide data architecture without moving into people management.
• Cross-Platform Technical Lead: Expand into a broader technical leadership role spanning adjacent platform domains.
• VP of Engineering / CTO Track: Progress toward an executive-level role based on experience in both technical strategy and organizational design.

 

Required Skills & Experience

Education

• Bachelor’s degree or higher in Computer Science, Information Engineering, or another relevant technical or quantitative field
• Equivalent practical experience may be considered in lieu of a formal degree

Professional Experience

• 8+ years of professional experience in backend or data engineering, including at least 2 years of experience as a Tech Lead or Architect
• In addition, strong expertise in the following areas:

Data Model Modernization for Existing Systems

• Experience designing and leading data model or schema modernization for large-scale production systems while maintaining service availability
• Ability to develop and execute phased migration plans

Relational Data Modeling

• Strong expertise in entity design, normalization/denormalization, index design, and transaction boundary design
• Experience establishing and implementing data modeling standards across an engineering team

Deep RDBMS Operational Expertise

• Strong operational knowledge of MySQL-compatible environments such as Aurora MySQL and TiDB, including query execution plans, slow queries, locking, and DDL operations on large tables
• Ability to quantitatively assess database capacity and scalability limits

TypeScript / Node.js

• Production-level software development skills
• Experience implementing and refactoring codebases involving large monorepos and shared libraries

Designing the Boundary Between OLTP and Analytics

• Experience designing the division of responsibilities between transactional systems and analytical platforms such as Snowflake
• Experience implementing architectures involving analytical workload offloading and reverse ETL from a data warehouse back into operational databases

Technical Decision-Making & Stakeholder Alignment

• Experience leading technology selection and investment decisions involving multiple stakeholders
• Ability to quantify trade-offs and gain consensus among both technical and non-technical stakeholders

Team Leadership & Development

• Experience mentoring and developing engineers
• Experience participating in recruitment processes, including interview design, interviewing, and candidate experience

Operations, Reliability & Governance

• Experience designing and operating SLOs and leading major incident response
• Experience designing data classification, access controls, and data retention policies as systematic processes

Language Skills

• Japanese: Business-level proficiency or higher, with the ability to communicate smoothly in Japanese across meetings, writing, and reading
• English: Sufficient proficiency to independently participate in technical discussions and create technical documentation, as collaboration with a multinational team is expected

Soft Skills

• Ability to translate business objectives into a technical roadmap and clearly explain prioritization decisions
• Strong discipline in knowing what not to decide yet, avoiding premature timelines and implementation details for out-of-scope or immature areas
• Ability to maintain engineering principles under pressure and resist shortcuts such as “bypassing the tools just this once”
• Ability to distinguish between tasks that should be handled personally and those that should be delegated, with a strong motivation to deliver results through the team
• Strong commitment to intentionally reducing dependency on individuals through documentation and systematic processes

Preferred Skills & Experience

• Deep knowledge of distributed SQL databases: Experience with capacity planning, garbage collection (GC), region design, and performance limits in systems such as TiDB
• Data warehouse implementation leadership: Experience leading the implementation and adoption of Snowflake or similar platforms, including cost management and defining the division of responsibilities between systems
• Data governance: Experience implementing data classification, lineage, Architecture Decision Records (ADRs), and data contracts; experience with data design and audit requirements considering privacy regulations such as the Japanese Act on the Protection of Personal Information (APPI) and GDPR
• Data retention policy design and negotiation: Experience defining and documenting data retention rules with business teams and incorporating deletion into standard operational processes
• Test strategy transformation: Experience leading the elimination of systemic causes of flaky tests and rebuilding test coverage across an engineering team
• Legacy modernization: Experience leading monolith decomposition, shared library separation, or planning and executing legacy system retirement
• Vendor collaboration: Experience designing and operating structured collaboration frameworks with database or data warehouse vendors, including regular reviews and escalation paths
• Cost management: Demonstrated experience analyzing infrastructure costs at the unit economics level and implementing cost reductions while communicating the impact to business stakeholders
• Community involvement: Contributions to open-source projects, technical writing, conference presentations, or similar activities

Ideal Candidate Profile

• Able to determine today’s priorities by working backward from the desired state 12 months into the future, rather than focusing only on immediate implementation tasks
• Able to explain technical constraints and risks in language accessible to non-engineers and move decision-making forward
• Comfortable making the decision to “not decide yet” when appropriate, treating it as an engineering discipline rather than avoidance
• Remains hands-on and is willing to personally tackle the most technically challenging problems
• Takes satisfaction in team achievements and is willing to invest time in helping others grow
• Strongly motivated to eliminate dependency on individuals through systems and processes
• Comfortable working in a global, multicultural environment and effective at using documentation and asynchronous communication

 

Compensation & Benefits

Salary: JPY 7,000,000 〜JPY 11,000,000per year
Probation Period: 3 months

Location
The position is based in either Tokyo or Osaka, depending on the candidate’s preference. Fully remote arrangements can be discussed on a case-by-case basis.

The company offers a flexible hybrid work style, combining remote work with office attendance. Frequency of office visits varies, typically ranging from once a week to once a month.

Working Hours

• Standard hours: 9:00 AM – 6:00 PM (includes a 1-hour break; overtime may be required)
• Flexible working hours with core time from 10:00 AM – 4:00 PM
• For employees above a certain grade, a discretionary labor system applies according to company policy

Holidays & Leave

• Saturdays, Sundays, and public holidays
• New Year’s holidays
• Summer vacation
• Bereavement leave
• Paid leave (10 days granted upon joining, with additional days accrued based on length of service)
• Other holidays as specified by company regulations

Benefits & Perks

• Commuting allowance (bicycle commuting permitted)
• Company-provided laptop
• Company-provided mobile phone (for certain roles only)
• Flexible start time program (can be applied for every 2 months)
• Social insurance coverage (health insurance, employee pension, employment insurance, workers’ compensation)
• Life & health support leave
• Coverage of medical check-up expenses
• Childbirth and childcare support programs
• Club activities and social groups

Measures Against Secondhand Smoke: No Smoking Indoors

 

Hiring Process

• Number of interviews: 3
• Application documents required: Resume / CV
• Interview language: Japanese and English

 

Please note: this position is open to candidates currently residing in Japan.