Senior Backend Engineer

At Mico, we develop and provide Mico Engage AI, a high-traffic enterprise SaaS platform. We are currently looking for core members to join the infrastructure development team of this product.

 

Why This Position is Attractive

• Work on the core infrastructure of the product and directly impact the business
• Tackle a wide range of technical challenges, including optimizing high-traffic systems, developing AI-powered features, and improving real-time processing infrastructure
• Collaborate with the Lead Engineer on technical decisions and standardization
• Gain hands-on experience refining a product in a fast-growing startup environment

 

Key Responsibilities

As a backend engineer, you will play a central role in the Mico Engage AI development team. Your responsibilities include:

• Stabilizing delivery infrastructure: Develop infrastructure that ensures stable delivery even for clients with a large number of users
• New feature development: Implement features to enhance product value according to the roadmap
• Customer-driven development: Develop reusable and highly requested features based on customer success feedback

 

Team Environment

• Multicultural, bilingual development team using Japanese and English
• Contribute to team and product growth while enhancing your skills in a global environment
• Encourage proposals not only for development but also for improving product value

 

What You Will Gain

• Experience in building scalable systems and implementing AI technologies
• Collaboration skills in a global development team
• Practical experience driving product growth

 

Tech Stack

• Web Backend: TypeScript (NestJS), Go, Elixir
• Web Frontend: TypeScript (Next.js), Chakra UI
• Databases: TiDB, Aurora MySQL, DynamoDB, Redis MemoryDB, Snowflake
• Infrastructure: AWS (Cognito, EC2, ECS, Route53, Lambda, Kinesis, SQS, SES, ElastiCache, RDS, CloudWatch, IAM, Audit, API Gateway, CodeDeploy), IaC (Terraform, AWS CDK)
• Middleware: Nginx, Supervisor
• Monitoring: NewRelic, Sentry, AWS CloudWatch
• Data Analytics: BigQuery, Google Data Studio, Google Analytics, Metabase, Trocco
• Environment Setup: Docker
• CI: GitHub Actions, Amplify Hosting
• CDN: CloudFront
• Source Control: GitHub
• Communication: Google Meet, Slack, Notion, Redmine, Jira, ClickUp

 

Required Skills

Experience:

• 5+ years of practical system development experience
• Ability to complete the full development cycle from specifications to release independently
• Strong coding skills with high-quality code implementation
• Ability to implement test code to improve quality
• Technical skills for prototyping and verification

Skills:

• Implement high-quality, maintainable code
• Implement test code to enhance quality
• Technical skills for prototyping and verification
• Design and build comprehensive architectures considering performance, scalability, security, operability, and cost
• Design, implement, review, test, and maintain backend code using TypeScript, NestJS, and any ORM
• Efficiently manage databases considering load, performance, and flexibility (e.g., SQL)
• Experience designing REST APIs
• Business-level communication skills in both Japanese and English

 

Preferred Skills

Experience:

• Product management experience for web/mobile applications
• Experience working in a startup environment

Skills:

• Design frontend code using TypeScript and React, implement production code and tests
• Design scalable code and architecture for high-volume data and traffic
• Experience with gRPC API development
• Development experience with Go
• Experience designing domain-driven or clean architecture

 

Ideal Candidate

• Can navigate ambiguity and undefined situations with curiosity and drive
• Makes technical decisions balancing short-term effort and long-term value
• Rapidly iterates on hypotheses and learns from failures
• Sets high standards through coding and reviews, inspiring the team
• Identifies product challenges and follows through to completion
• Collaborates with multinational team members and openly shares knowledge

 

Work Location

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

 

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

 

Probationary Period

• Generally 3 months (no changes in compensation or benefits during this period).

 

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

 

Hiring Process

• Document Screening
• Casual Interview (Japanese Language Check)
• Cording Test
• First Interview
• Second Interview
• Reference Checks
• Final Interview
• Job Offer Meeting

*The hiring process is subject to change.