Hello, I’m Masaki from the PayPay product team.

This year, PayPay participated in the hackathon “Internal Hack Day” held at Yahoo! JAPAN.

You can see report by each participating company here (Japanese).

What is the Internal Hack Day

Since 2007, this hackathon has been held once a year by Yahoo! JAPAN.

Hackathon celebrates freedom of thinking, creative effort within a limited timeframe, and original development, with creators playing a leading role

Employees form a team, make a prototype that can ship within 24 hours, and give a 90-second presentation.

The theme of this year’s event was “Solving problems with a new lifestyle.” and with recent troubles in mind, the event fully remote.

PayPay Product Team

PayPay has never joined a hackathon event before, so this was a new experience for a lot of our members. We had three teams participating, each working on their own original ideas, which I will briefly introduce here.

Please note that the ideas presented here were created as hackathon prototypes, and do not represent actual product features that PayPay intends to release.

Merchant Match

This is a PayPay marketing tool that uses machine learning.

The idea behind the tool is that it would allow merchants to target users who are similar to existing customers, and can create offers based on user behavior.

This work uses Matrix Factorization, which is often used in recommendation systems, and is calculated using the ALS algorithm.

Do perfect Yoga

A PayPay mini app that allows you to practice yoga online.

It is intended to be used as a healthcare source for users and as a source of income for yoga instructors.

Look for more on this later, as will plan to publish reports by individual team members that created this mini-app idea.

PayPay for Kids

This is a mini app that allows you to send pocket money to children using PayPay.

The child user can suggest the type of help that they will offer, and a parent user can approve it.

Not only does this create a good opportunity for children to experience cashless society, but it also encourages intelligent money management.


Through the joining an event like this, one that goes beyond the boundaries of different companies, we were able to interact with engineers and designers in the field and share different expertise. This is something we want to continue to do in the future, as we look to expand connections and provide more richer services to the world through our synergies.

Everything we learn at an event like this is knowledge that can be fed back into our product teams, helping us to look at PayPay in a new way, and improve our own work .

Coming up next, on July 22 (Wednesday), is AWS Night. This is an online event jointly held with ZOZO Technologies and Ikkyu. We will be looking at how each company is using AWS, so please join us!

[Online] ZOZO × Ikkyu × PayPay AWS Night