Senior Backend Engineer

About the Company

PayPay is a fintech company providing a service enjoyed by over 70 million users. The company is home to a very diverse team of members from more than 50 countries, operating with an AI-first culture where engineers actively leverage AI tools for code reviews, testing, and productivity.

Responsibilities

• Design large scale systems with high complexity to support high throughput applications
• Leverage infrastructure for solving large scale problems
• Develop tools and contribute to open source wherever possible
• Adopt root cause problem solving and support production code

Requirements

• 6+ years of experience in Java and another language like Scala, Python, or Go
• Experience with SQL and NoSQL databases and distributed cache
• Strong fundamentals in data structures, algorithms, and object-oriented programming
• In-depth understanding of concurrency and distributed computing
• Experience implementing RESTful APIs, Pub/Sub Systems, and Database Clients
• Experience with microservices and designing high traffic systems
• Degree in Computer Engineering, Computer Science, or 5+ years equivalent experience
• Business proficiency in English or Japanese

Preferred Qualifications

• Experience in system development for finance or payment industries
• Language ability in both Japanese and English
• Experience with AWS services
• Ability to leverage AI/LLM-based tools in daily engineering workflows