【Tokyo】TECH-Bizclo-01. Lead Full Stack Engineer (Bilingual)

At BizClo, you’ll have the opportunity to take ownership of and modernize the architecture of a high-traffic enterprise SaaS platform used daily by leading businesses. You’ll tackle challenges such as scaling real-time messaging systems, enhancing the developer experience, and refactoring complex features—all while helping to set engineering standards for a fast-growing product. This role isn’t just about solving technical problems; it’s also a chance to grow into a trusted technical leader, mentor others, and thrive in a bilingual, multicultural team environment. By collaborating with both Japanese- and English-speaking colleagues, you’ll expand not only your technical expertise but also your ability to lead and influence in a truly global context.

◼︎Job Summary
BizClo is an enterprise-focused LINE chat SaaS platform handling a massive volume of messages and high-traffic request processing daily. The product delivers experiences that improve　operational efficiency and drive sales through 1-to-1 communication.
In this role, you will tackle challenges such as modernizing and refactoring increasingly complex internal and customer-facing features, improving developer experience, balancing real-time responsiveness with system stability, and paying down technical debt.

◼︎Key Responsibilities

• Drive system design and development with an emphasis on modularity and reusability to accommodate flexible customer requirements. Actively work on design improvements based on current architecture and challenges.
• Lead continuous improvements based on various metrics to enhance service responsiveness and stability, and establish and execute operational indicators.
• Manage a shared foundation that connects design and implementation while maintaining UI quality.
• Improve developer experience by shortening build times, refining review processes, and expanding automation.
• Facilitate environments that support technical decision-making and actively support the growth and mentoring of junior members.
• Collaborate and document effectively with global teams using both Japanese and English.

### Language and Platform
- TypeScript
- Node.js / pnpm / Turborepo

### Front-end
- Next.js
- Chakra UI / ShadCn 

### Back-end
- NestJS
- Prisma ORM
- Kafka、Redis、Elasticsearch

### Infrastructure and Operations
- AWS（S3、Cognito、SQS）
- Terraform、GitHub Actions

### Monitoring and Quality Assurance
- New Relic、OpenTelemetry
- Jest、Playwright、ESLint、Prettier

Employment type
Full-time employee
Probationary period:Generally 3 months (no changes in compensation or benefits during this period).

Salary
Salary will be determined based on previous experience, taking into consideration your skills and expertise.

Work Location
- Your preferred work location will be discussed.
- Flexible work styles are available depending on job responsibilities (remote/on-site).
 
▪️Average On-Site Frequency
- About 4 days per month.

▪️Osaka Office
WeWork Midosuji Frontier 1-13-22 Sonezakishinchi, Kita-ku, Osaka-shi, Osaka Prefecture
 
▪️Tokyo Office
WeWork The ARGYLE Aoyama 6F 2-14-4 Kita-Aoyama, Minato-ku, Tokyo

Work Hours
- Standard Schedule: 9:00 AM – 6:00 PM (includes a 1-hour break; overtime applicable).
Flexible Time: Core hours from 10:00 AM to 4:00 PM.
-  Certain grades may fall under a discretionary labor system, per company regulations.

Holidays and Leave
- Weekends (Saturday & Sunday), national holidays
- Year-end and New Year holidays
- Summer vacation
- Bereavement leave
- Paid leave (10 days granted upon joining, with additional days based on tenure)
- Other company-designated holidays

Employee benefits
- Commuting allowance (including bicycle commuting)
- Company laptop provided
- Company phone provided (*role-specific)
- Flexible start-time policy (every two months upon request)
- Social insurance (health, pension, employment, workers' compensation)
- Life and health support leave
- Health checkup expenses covered
- Parental and childcare support programs
- Club activity support

MUST

• Extensive practical experience (around 5+ years) in developing medium to large-scale web applications
• Experience designing, implementing, and operating UI using React + Next.js
• Experience designing and operating scalable backend systems using Node.js + TypeScript
• Understanding of datastore design including RDB, NoSQL, and message queues
• Experience with DevOps practices utilizing CI/CD and Infrastructure as Code (IaC)
• Ability to conduct technical discussions and create documentation in both Japanese and English

Preferred 

• Experience leading improvements in development infrastructure, performance, and monitoring
• Experience designing and improving real-time processing for high-traffic systems
• Practical experience complying with security and privacy guidelines and regulations
• Track record of external contributions (OSS, conference presentations, technical blogging)

Ideal candidate profile:

• Ability to move forward from ambiguity and undefined situations with curiosity and drive
• Balances technical decisions considering short-term effort and long-term value
• Rapidly iterate on hypotheses and learn from failures
• Sets high standards through code and reviews, inspiring the team
• Identifies product challenges and follows through to completion
• Collaborates with multinational members and openly shares knowledge