Tech Talks vol.6 – User Module

About Tech Talks

In this Tech Talks series, we share the everyday life of the PayPay Product team through the eyes of members from over 35 countries around the world. This time, Xiao Han from the User Module team will share his story.

*A Japanese version of this article is also available.

What I’m Working on Currently

The User Module team is in charge of some of the most important microservices in PayPay’s backend, like authorization, user management, and notification.

I spend half of my time implementing new features for these services and the other half supporting my team members, as well as reviewing code and designs.

The User Module Team

A Technical Challenge I Experienced Recently

Recently, I’ve been working on the design of an authentication and authorization framework for all our backend services. We take security seriously and invest heavily in improving system security. At the same time, it is hard to design a secure authorization system that matches PayPay’s scale, so I have to consider the performance impact as well as operational complexities. There are a lot of tradeoffs to make. It’s an interesting challenge to have.

What I like to Challenge at PayPay

I have a lot to learn at PayPay. I want to focus on our team first. As we are the backbone of all PayPay’s backend services, I want to build a robust and feature-rich service for all of PayPay’s engineering teams. Also, I believe large software can only be built by teams. I like to work with all of my team members to build good software systems and bring more value to our users. In the future, I would like to be a good engineer manager and build great teams at PayPay.

My Typical Daily & Weekly Schedules

My Career Before Joining PayPay

After graduating from college in China, I joined a large Japanese ERP company. I worked in Shanghai for a year and then transferred to the Tokyo headquarters. During the following five years, I worked on various projects and had multiple roles, including backend, cloud infrastructure, and SRE.

After that, I moved to a small A.I. startup where I developed backend services and used deep-learning models to convert paper documents into digital data. One year later, PayPay started hiring. So, I joined and have worked here since.

The Reason I Decided to Join PayPay

I’ve always been interested in consumer products. When PayPay launched, it caught my eye immediately. The PayPay app is well-designed and extremely easy to use. I knew there must be a very good team behind it, so I decided to apply for a position.

During the interview, I met with several Day 1 engineer and managers. I was impressed by their technical skills and enthusiasm for the product. Also, I learned that the team is very diverse, and they have a good company culture. I felt PayPay was a good place to improve my skills as well as an interesting place to work. That’s why I’m here now.

A Message to Aspiring PayPay Employees

At PayPay, we are building a product that is used by so many people. Our software system is very big, there are many challenges to overcome every day, and there are many awesome people from all over the world. You can’t find another place like this in Japan.

If you love to build great products, take on tough challenges, and work with smart people, join PayPay.

*The recruitment status is current at the time of the interview.

Author: Han Xiao / Editorial Supervisor: Mune / Managing Editor: Az
* Employee affiliations are as of the time of the interview.