PayPay Inside-Out People and Culture

Tech Talks vol.7 – Platform (DBA)


About Tech Talks

In this Tech Talks series, we will directly share with you the attitude and vibe of the PayPay Tech team through the voices of the unique product members from over 35 countries! This time, Son Nguyen from the Platform team will share his story.

*Japanese version of the article is also available.


I have been working with the Platform team for almost nine months since I joined PayPay in October 2020.

What I’m working on currently:

As a team member, I am mainly working on TiDB, an open-source distributed SQL database that features horizontal scalability, strong consistency, and high availability. Specifically, I am working on the following tasks:

  • Performing Database Reliability Engineering (DBRE) tasks to keep current TiDB systems reliable.
  • Migrating Amazon Aurora MySQL clusters to TiDB clusters to help resolve the bottleneck at the database layer.

The Platform Team:

At PayPay, the Platform team is responsible for the PayPay app infrastructure. Members are working on many different technologies such as Amazon Web Services and self-managed services, for example, Argo CD, Kubernetes, Kafka, and TiDB, etc.

A Technical Challenge I Experienced Recently:

One of the most challenging technical issues that I have experienced recently is involving in a project to upgrade a version of the TiDB system which hosts tens of terabytes of data. Since the TiDB system version is pretty old, the upgrade process became more complicated, and the workload was enormous. However, with the great support from my mentor and other seasoned engineers, I was able to fulfill almost all tasks. As a result, the project was completed on schedule. Thanks to this experience, I have learned almost all aspects of a TiDB system. As a result, I feel more confident in operating TiDB systems at PayPay.

What I like to Challenge at PayPay:

Fortunately, I had some opportunities to work on many different technologies, and these experiences helped widen my perspectives about technologies in the IT field. It is time for me to deep dive into the distributed SQL database because I want to become a Subject Matter Expert (SME) in this area.

My Typical Daily & Weekly Schedules:

As our team also uses the Scrum Framework to manage our work. Every week, we hold a Sprint Retrospective and Sprint Planning meeting to review what we have done last week and plan for the next Sprint.

Accordingly, my daily schedule starts with a scrum meeting. Here I talk about what I did yesterday, what problem I am facing, and what I will do on the day. Then, if I encounter any hindrances, I will ask for advice from my teammates and my leader at the end of the meeting.

Since I joined PayPay, every day has become a new challenge, new adventure, and new opportunity for me to overcome, discover, learn new things, and sharpen my skills because I’ve been working on TiDB, a distributed SQL database. It’s quite a complicated database system that makes use of many different areas in computer science. Sometimes, I face a complicated problem that I cannot find effective solutions for. However, that is the time I can learn a lot from others.

My typical working day ends with a daily retrospective and next day planning session I create for myself. I take note of what I did on the day, what problem I faced, and plan for what I will do the next day.

My career before joining PayPay

Before joining PayPay, I experienced two positions, a Site Reliability Engineer and a Data Engineer in the same Tokyo-based health-tech startup for more than three years.

As a Site Reliability Engineer, I worked on many different things across the tech stack, from Application Performance Monitoring (APM) and Distributed Tracing to CI/CD, Container Services, Databases, and Infrastructure Security.

One of my remarkable contributions to the company services’ reliability and cost-optimization was that I architected the Infrastructure so that Microservices can auto-scale 100% on AWS to handle incoming requests at peak hours promptly and cut costs (mostly EC2 costs) at off-peak hours (

Moving on, I took up the position of Data Engineer. I was responsible for building and maintaining a Big Data warehouse and a data lake. I also had an opportunity to work on a Machine Learning project that builds a predictive model for optimizing Push Notifications. As a result, I learned a lot about workflow for creating a production-ready machine learning model from this project.

The reason that I decided to join PayPay

When I was looking for a new job opportunity, I chose PayPay to apply because I found that PayPay app is a useful app for my daily life. I started using the PayPay app from the beginning of 2020, and I clung to it from that time onwards since I don’t need to bring my physical wallet every time I go to a convenience store or supermarket. Personally, I really like working on the product that I find useful for me first.

Secondly, while doing some research on PayPay, I found that PayPay is a fast-growing fintech company in Japan with a large number of users. Fast-growing in terms of user base means the PayPay app has been rapidly becoming a helpful utility for many people’s daily life. Accordingly, more technical challenges are likely to occur. Therefore, it is my great pleasure to work on such an incredibly useful product. Furthermore, handling technical problems will help me hone the necessary skills for higher career growth in the future.

A Message to Aspiring PayPay Employees:

PayPay is a fast-growing fintech company with an increasing number of payment transactions. Accordingly, the number of technical challenges is growing, and the scope is also becoming bigger and bigger. For example, we are upgrading Amazon Aurora MySQL clusters continuously to adapt to Transactions Per Second (TPS) increments. We are continuously devising ways to improve scalability and reliability.

By joining my Platform team at PayPay, you will have opportunities to work on intriguing technical problems in the database layer, such as solving scalability and reliability problems that we are struggling with Amazon Aurora MySQL clusters. You will also have opportunities to learn about distributed SQL database systems, for example, TiDB and others.

In addition, PayPay offers the Work From Anywhere at Anytime (WFA) workstyle which allows you to work from anywhere in Japan at any time. Where you work and where you currently live do not matter at PayPay as we work remotely. You can receive a salary and benefits which meet the global standards and work with world-class talents while working in the countryside. Furthermore, regardless of whether you are an English speaker or a Japanese speaker, PayPay enables you to join English and Japanese classes to improve your language skills.

In a word, working on a useful product for tens of millions of people’s daily lives makes me proud of every task I do. I am confident that you will feel the same way as I do when joining PayPay. Thank you so much for your attention!

Currently available position

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