PayPay Inside-Out People and Culture

Tech Talks vol.16 – Backend Engineer


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 around 40 countries! This time, Harvey Cheng from the Finnet Services & Bill Payment Team will share his story.

Harvey Cheng

Harvey Cheng

Backend Engineer

As a backend engineer in the Product Division, I belong to the Backend Team in the Finnet Services & Bill Payment product line. It has been almost one and half years since I joined PayPay (from January 16, 2021).

*The Japanese version of the article is also available here.

What I’m working on currently

Although I’m the tech lead of the Backend Team which includes finnet, bill payment, and KYC, I’m also the sub-leader of one sub-team which is focused on KYC.

So, I focus on system design, quality assurance, improvements, and parts of project management for each project. I spend only 10% to 20% of time per month for coding.

A technical challenge I experienced recently

PayPay moves fast, so we were able to successfully complete many things in a short period.
However, how to manage the knowledge and make the system maintainable is a different thing.

One case in point. A few months ago, we had a migration that handled the encryption of a large amount of data. Although we completed it easily without any problems, the knowledge about how to handle it was still owned by only a few people. And, unfortunately, we actually found some detailed information of the operation from a long time ago that was missing. By now, no one knew how we encrypted old data, and the encrypted data was not compatible with new logic.

We solved this problem by consulting with the Platform Team members, then double checking with people in other teams, and making decisions for a workaround.

Anyway, to improve this, what we did was to keep updating documents, and share the knowledge about the tech that we used to all team members. The important points we made as regards to keeping records of the documents were: the background, how we handle it, the tradeoff, potential risks, and then sharing that information with everyone. Furthermore, we started assigning related tasks to members who did not have experience in those particular assignments.

Challenges I want to take on at PayPay

As tech lead, I still need to gain more knowledge about the features handled by my team since I still focus on managing a small part only.

PayPay has many kinds of features. To be able to consider the overall architecture, design, and managing resources for them will be very interesting and challenging. No matter whether I am an individual contributor or a leader, I would like to get the opportunity to handle full features across multiple teams.

My typical schedule

To keep a healthy working culture, I try my best to work during the day and avoid working at night.


Wake up at around 8:30 a.m.
Ride my bicycle to the office at around 9 a.m. after taking a shower.
Take a free coffee first and then check messages on Slack to have an overview of tasks
Start handling inquiries and then review PRs and check progress.
Join daily sync with backend members at 1 p.m.
Log off and go to the gym at around 7 to 8 p.m.

Of course, meetings and discussions take up most of my time. Plus, we have many additional tasks which do not belong to regular projects, some of which I handle myself between 10 a.m. to 6 p.m.

My weekly schedule

  • Sync between tech leads for 30 minutes. Check schedule and resources.
  • Review and plan sprints for 30 minutes.
  • Sync project status with PMs for 30 to 60 minutes.

My career before joining PayPay

I worked in diverse fields in Taiwan before joining PayPay, which include a startup telecom service provider, local company for GIS products, system integrator focused on telecom and banks, e-commerce company with the largest market in Taiwan, and gambling companies.

I worked in various roles from developer to tech lead, in small to big companies, technical and non-technical companies, and collaborated with various kinds of business teams. I learned how to manage the balance between business, tech, and management.

Why I decided to join PayPay

When I first came to Japan many years ago, I was shocked by the working attitude of people in Japan. I thought it made for a great environment. So, I wished to have the chance to try and learn to work in Japan.

But I wanted to work in a company with an open culture, and I can’t speak Japanese… Besides, I always preferred working for useful products that I do use as well, instead of only coding for money.

Based on all of the above, PayPay was a really good choice for me to work in Japan.

Attractive points about working in PayPay

  • Young. PayPay has many kinds of new features and new challenges to handle. It is never boring here and your skills are always put to the test.
  • Open culture. English is the official language for communication, which allows us to have members from different countries with various cultures, as well as accept different ways of thinking.
  • The company’s strong business requires well-built technical systems to support large amounts of transactions.
  • You can choose to work in a comfortable office or remotely. We have offices in many places.

Message to aspiring PayPay employees

PayPay is a highly useful product with tremendous market potential, supported by a large-scale system which requires members with solid skills to build. And, it is still growing at high speed.

We welcome people from any country without language barriers and provide various working styles.

You can find the position you want here.

Currently available positions

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

Author: Harvey Cheng / Editorial Supervisor: Mune / Managing Editor: Az
*Employees’ affiliations are as of the time of the interview.