[Software Engineer / Full-Time] Develop New Services for "Social EC" Kauche | Full-Stack Engineer Wanted (Updated 6/29)Translated from Japanese

Job title: [Software Engineer / Full-Time] Develop New Services for "Social EC" Kauche | Full-Stack Engineer Wanted (Updated 6/29) ▼Job Description [Work Content] In the newly established New Service Development Office, you will be responsible for the overall launch and development of Kauche's new product areas. This position focuses on full-stack development, creating new customer touchpoints and product experiences, including LINE Mini Apps, in collaboration with the existing Kauche Farm infrastructure. [Specific Work Content] 1. 0 to 1 Development of New Product Areas - Design and development of new services to be integrated into the Kauche app. - Technical verification, prototyping, and full-scale development of new customer touchpoints and channels. - Planning and implementation of new features that expand the strengths of Gamification x EC. 2. Practice and Evolution of LLM-Native Development Processes - Refine the development process starting with Claude Code and establish a process for end-to-end delegation to LLMs from PRD. - Establish and improve a workflow for managing PRDs on GitHub and automatically generating detailed specifications and implementation code with high accuracy. - Operate an iterative development cycle that confirms the feasibility of specifications by updating demos. - Develop development infrastructure that generates maximum output with a small team. 3. Design and Integration with Existing Infrastructure - Design connection with existing backend APIs (Go / gRPC). - Design authentication and account linking. - Develop analytics infrastructure (event log design, KPI measurement). ▼Required Skills/Experience - Practical experience of at least 2 years in development and operation. - Excluding PoCs, internal services, etc. - While the current team members are mostly in their 30s, the number of years of experience is not heavily weighted; we prioritize individuals who are eager to practice software development at a high level. - Ability to drive software development with ownership. - Experience practicing development processes utilizing AI tools (Claude Code, Cursor, Codex, etc.). ▼Welcome Skills/Experience - Backend development and operation experience (Go, Google Cloud, etc.). - SPA / Web application development experience with modern frameworks such as React / Next.js. - Tech lead, team building, and process improvement experience. - Architecture design and technology selection experience. - Frontend, mobile app development experience, or PM experience. - Development experience with TypeScript. - WebView-based app or mini-app development experience. - Product development experience including gamification elements. - Growth strategy implementation experience in EC / B2C products (A/B testing, retention improvement, etc.). - 0 to 1 product launch experience. - Tech lead and team building experience. ▼Ideal Candidate Profile [Those who resonate with Kauche's values] - Those who resonate with Kauche's vision: "Creating the world's most enjoyable shopping experience." - Those who resonate with Kauche's values: "Enjoy Working, For Team, Try First." - Those who want to create a more enjoyable world through entertainment, community, and social shopping experiences. [Those passionate about launching new products] - Those who are excited about 0 to 1 new product development. - Those who want to be involved from the discussion of what to build and shape products from the PRD level. - Those who enjoy covering multiple domains with a small team. - Those who can move forward by repeating hypothesis testing without fearing uncertainty. [Those who want to promote AI-driven development] - Those who are proactive in development using AI tools like Claude Code. - Those with a system-oriented mindset who can create an accelerating environment, rather than believing "more people means faster." - Those who are motivated to build and improve new development processes themselves. [Those who can operate full-stack] - Those who can handle backend and infrastructure as needed, while focusing on the frontend. - Those who want to compete at the forefront of B2C services. - Those who want to challenge themselves in a massive market exceeding 10 trillion yen. ▼Job Appeal - Experience 0 to 1 new product development directly under CXO. This is a rare opportunity to launch a new product from scratch on a user base with a cumulative 5 million downloads and top-tier engagement time. The CPO directly leads the team, and in an environment with extremely fast decision-making, you can be involved end-to-end from product direction discussions to implementation. - The forefront of AI-native development style. AI-driven development centered around Claude Code is the standard. You can experience creating products at several times the conventional speed by utilizing AI consistently from design to implementation. You will also be involved in building new development processes that formulate "implementation plans" and delegate them to AI. - Technical challenges for new channels and products. We are not limited to existing native apps but are working on building new customer touchpoints through web applications and collaborations with external platforms. You will be involved technically in viral design and growth strategies that leverage the uniqueness of Gamification x EC. - Collaboration with excellent members from mega-venture companies. The development organization is lean and consists of many experienced senior engineers from companies like DeNA, Mercari, CyberAgent, and Raksul. You can collaborate with technically high-caliber members, including Mr. Shibata, who advocates and promotes "API Specification First Development." ▼Development Environment - Languages: TypeScript (Frontend), Go (Backend / Existing Infrastructure) - Frontend: React / Next.js - API: Protocol Buffers, gRPC (Integration with existing infrastructure) - Infrastructure: Google Cloud (Cloud Run, Cloud Firestore, Cloud Spanner, etc.) - Monitoring: New Relic, Cloud Monitoring, Cloud Logging - Analytics: Google Analytics, Firebase Analytics, BigQuery - CI/CD: GitHub Actions, Cloud Build - AI Development Tools: Claude Code - Others: GitHub, Notion, Figma, Slack - Development Style: Agile Development (5-9 deployments per day, 12 feature releases per month) ▼Employment Type Full-time employee (No fixed term) ▼Probationary Period 3 months ▼Salary Annual salary ¥7,200,000 - ¥15,600,000 ▼Annual Salary Lower Limit (10,000 JPY) 720 ▼Annual Salary Upper Limit (10,000 JPY) 1552 ▼Work Location Asia Building 9F, 1-12-16 Jinnan, Shibuya-ku, Tokyo 150-0041 Commuting Frequency: Hybrid work (3 days in office per week) *Scope of Change: Headquarters and all branches and sales offices nationwide. ▼Working Hours Flextime system (applicable to all positions for full-time employees) - Standard working hours: 8 hours per day - Flexible time: 6:00 - 22:00 - Core time: 11:00 - 15:00 - Break time: 1 hour, flexible to take ▼Break Time 60 minutes ▼Overtime Work Yes ▼Holidays, Paid Leave, Special Leave - Complete two-day weekend system (National holidays, New Year holidays, etc.) - Annual paid leave - Special leave (5 days upon joining) - F-Leave (Leave for women's health issues/examinations / once a month) - Congratulatory and condolence leave - Maternity and childcare leave - Childcare and nursing care leave ▼Benefits - Stock options that do not expire after leaving the company. - Club activity system (partial subsidy for activity expenses). - Book and seminar subsidy system. - Subsidy for welcome and farewell parties. ▼Allowances - Commuting allowance (up to ¥30,000 per month). - Referral recruitment allowance. - KAUpos allowance (peer bonus system). ▼Insurance Enrollment Health Insurance / Employees' Pension Insurance / Long-term Care Insurance / Employment Insurance / Workers' Accident Insurance ▼Measures to Prevent Passive Smoking at the Workplace Indoor smoking prohibited in principle (smoking area available) ▼Education/Skill Up/Career Up Book and seminar subsidy system ▼Health Consultation available with contracted medical professionals / On-site industrial physician available ▼Interview/Selection Process Document screening → Interviews (multiple) → Skill assessment → Reference check → Final selection ▼Other *This position requires advanced communication skills in Japanese, therefore Japanese proficiency equivalent to JLPT N1 or higher is a mandatory requirement. ■ Recruitment Page https://enjoy-working.kauche.com ■ Composition Kauche's Backend Architecture: https://note.com/kauche/n/n81e086ec5745