Tech Talks vol.23 – App Platform Team

About Tech Talks

In this Tech Talks series, we will share with you the attitude and vibe of the PayPay Tech Team through the voices of the unique product members from around 50 countries!
For this installment, we talked with five engineers on the App platform team.

What does the App platform team do and what is its mission?

Richard：
Our team is building a common platform for iOS and Android. Consumer Android and consumer iOS are usually developed separately, but in reality there are many similarities, including platform and code.
Our team has started investigating a mechanism to share business logic that can be shared on a single code-based platform. Currently, we have already shared codes between iOS and Android and have also created a common library.

Rajanikant：
If this initiative moves forward accordingly, we can make development more efficient.

Yoseph：
Yes, that’s right. The biggest advantage of a common platform is that it reduces the development effort of engineers dramatically. In PayPay, Android and iOS were originally built with a different logic, but we are aiming for significant improvements by creating a common platform.

Can you give us some specific examples of your work?

Richard：
As a team, our goal is to provide SDKs and reduce development man-hours for consumer app engineers, but we also have members consider their own missions and share the workload.

Rajanikant：
In my case, my long-term goal is to provide a better development environment, and to that end, I am working on CI tasks and visualization of the workflow.

Travis：
I am in charge of a similar area. My mission is to increase development efficiency and improve developer experience.

Kuan-Yi：
I am a little different from Rajanikant in that I am working more on the feature side like adding new features or improving existing features, to ensure that our SDK is aligned with the changes on the app side, so that the developers have less to worry about when developing new features.

Yoseph：
In my case, I’m working on Kotlin Multiplatform development, and I’m developing a very customized version for the PayPay app. We started the initiative in earnest in 2022, but there were hardly any companies in Japan doing this kind of development. It’s like a journey to uncharted territory and mapping it for the first time, so I’m still learning and dealing with it every day. It feels like I’m only fixing bugs over and over again, but it is a great way to improve my skills.

Could you describe some challenges you face at PayPay?

Yoseph：
When I joined the App platform team in early 2020, it was really full of challenges—both iOS and Android. Our team had to make improvements with the same method, so it was extremely difficult. The framework was not good enough, so we had to spend a lot of time customizing it to get it up to production. There were many obstacles we had to overcome to bring it to a production-ready level.

Kuan-Yi：
It is very challenging to implement something new that will affect apps that are already running. I’ve set up toggles so that we can quickly revert if something goes wrong depending on the platform we are developing. We have to check carefully and make improvements without breaking the parts that PayPay users come in contact with.

Travis：
For me, the initial problem was that I didn’t understand Japanese when I joined PayPay (laughs), but now I can work normally using English. Also, the framework we use at PayPay is fairly new and experimental, which means it has a technical structure that no one has used yet. So I first had to understand everything PayPay has done in the past two years. It was really tough to catch up.

Rajanikant：
I agree with Travis. There are not many companies using KMM, so I think we are getting a very valuable experience.

What are some attractive points about working in PayPay?

Kuan-Yi：
PayPay is used throughout Japan and has a large service infrastructure that is available whether you are shopping at a supermarket or going to a restaurant. Just by hearing the “PayPay♪” jingle, I can observe first-hand how many people are using the fruits of my hard work. Getting to do work that impacts people’s lives is a truly unique experience.

Rajanikant：
I’m a heavy PayPay user myself, and I can find products that I have created just by exploring the app, which is very motivating.

Richard：
In terms of working style, working in Japan is interesting in and of itself, but I also enjoy working in a fully remote environment through the WFA (Work from Anywhere, Anytime) system. This is actually the first time the whole team has actually met face-to-face, but I think the fact that we are all working together with the same passion makes working at PayPay even more fun.

Travis：
I was already proud before I joined the company to be engaged in the creation of an app that I use every day (laughs). From a technical standpoint, it is very exciting to be on the cutting edge, to be exposed to code that I have never seen before, and to be able to make improvements.

Yoseph：
It is also a great feeling to work with the idea that I am helping Japan go cashless. In terms of skills, my main experience has been with Swift, but since I joined this team, I have come to like Kotlin and have been able to catch up on KMM and Android development, which has been a great experience.

Kuan-Yi：
Our Multiplatform approach is not a completely new idea. There are several foreign tech companies that have already created their own platforms, but the major challenge for PayPay was how to ensure stable operation using a new technology. We have so many users and so many devices, so finding a way to achieve stable operation on all of them was a very interesting challenge, but with its fair share of concerns. Naturally, some things that did not go well, but after about a year of work, the improvements finally bore fruit. We were able to prove the results and validity of Multiplatform to the people around us, and I think we are starting to gain their trust (at first, most people were skeptical).
We continue to make improvements, and step by step, are getting a little bit closer to what we are aiming for.

Tell us about your team!

Yoseph：
I think one positive characteristic of the company is that everyone is open-minded about new technologies. It’s wonderful that everyone here has the same attitude, and it’s not uncommon to hear people say, “Let’s try it first” or “How about linking with this plugin?”

Travis：
Yes, we are open-minded and there is no one who will outright deny a new idea. We certainly work in an environment where we start with “Let’s give it a try,” even if we’ve never done something before, and the results follow.
I think the atmosphere of the team is great. Actually, I was a little worried about the culture before I joined because PayPay is a major Japanese company, but it was a pleasant surprise to be able to work with such frank and friendly colleagues. I am definitely enjoying it.

Kuan-Yi：
All five of us are from different countries. Despite the varying backgrounds, we work together to solve problems in areas we have never set foot in. Sometimes the issues are not immediately solvable, but we collaborate to find ways to. The speed at which PayPay conducts business and the evolution of technology are so rapid that I feel like I have to fully exert myself to keep up with both, even just to figure out if there is anything new I can do. We constantly have to catch up with the latest technology and make improvements.

Tell us what you hope to accomplish in the future!

Richard：
Last year, the immediate challenge was to keep our platform running stably. Thanks to KMM, we have been able to make improvements and overall stability is better. Going forward, I would like our team to be involved in the new features that will be implemented in the PayPay app. That is our ultimate goal.

Travis：
User Experience is a well known term people are focusing on these days but how about us developers? KMM is similar to Android so the integration is pretty smooth, but not so much on the iOS side. Once we get the Developer Experience right, we can focus our time building better User Experience.

Yoseph：
Yes, the platform is still in its infancy on the iOS side.

Kuan-Yi：
I think it is also important to change the mindset of developers, from “Can we do it on the KMM?” to “Let’s do it on KMM SDK!”

Rajanikant：
Personally, I would like to increase the amount of common code. I know it’s ambitious, but I’d like to aim for 100%!

Finally, do you have a message for potential candidates?

Richard：
I encourage anyone interested in KMM to apply. This environment is filled with opportunities to learn new things and gain engineering skills that you may not have experienced before.

Rajanikant：
It’s a fun job if you like Kotlin and are interested in Multiplatform.

Yoseph：
If you like to try new things and are open-minded, I would love to work with you!

Kuan-Yi：
PayPay has a large nationwide service base, and being involved in the development of our products is a valuable experience. Nonetheless, you can still work in a small team like ours and be exposed to new technologies. It is an environment that will lead to career growth for sure.

Travis：
If you are excited about a job where you can break new ground, we would love to work with you!

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

Special Thanks: Richard, Kuan-Yi, Travis, Yoseph, Rajanikant / Editor: Moe / Author: PayPay Inside-Out Editorial Team / Photographer: Yuki
*Employees’ affiliations are as of the time of the interview.