Magazine Software Design April 2023: Interview with Daichi Horio and Ryo Tomaru [ part 1 ]

It first appeared in a Japanese magazine, and after Cocone received permission, it was translated into English and published.
first appearance: Software Design April 2023 ( Gijutsu-Hyoron Co., Ltd. )

Explore Cocone’s engineering capabilities to open up a new era of Web3

Top-level performance in the world’s favorite digital world

1st Global Expansion by Incorporating Strategy and NFT into Janken, a Game Everyone Knows

“JANKEN” was launched as a Play & Earn blockchain service that allows players around the world to play for free on an equal footing, with the goal of making the game of rock-paper-scissors that everyone knows so well into entertainment. We asked Mr. Daichi Horio and Mr. Ryo Tomaru of Cocone about the application overview and what kind of technology it consists of.

– Please introduce yourself.Daichi Horio (Horio)

My name is Daichi Horio, Team Leader of JANKEN Project Development Team, Cocone Corporation. I moved to Cocone after working for an online game development company. At first, I was involved in the development of “Pokecolo Twin”, and now I am a development leader of JANKEN Project, mainly working on client development.

Ryo Tomaru (Tomaru) I am also a member of the JANKEN Project Development Team. I joined Cocone because I wanted to be involved in the development of services that mainly focus on communication between customers. I joined the company as a client engineer at first, but since I also had experience in server development using real-time communication, I am in charge of server development in the “JANKEN” development team.

– What kind of application is “JANKEN”?

Horio: Although the expression of janken differs slightly from country to country and region to region, it is a hand game whose rules are known by people all over the world. Taking advantage of this merit, “JANKEN” allows players to play rock-paper-scissors-scissors with anyone in the world, with open beta starting globally on December 15, 2022 (Japan is not a service country at this time). While the rules for winning and losing are the same, “JANKEN” adds a strategic element that is original to “JANKEN. When a game begins, both you and your opponent are dealt three cards, Rock, Paper, and Scissors, and one additional card from the Goo, Choki, and Pa cards is dealt to each of you. The winner is the player who wins the first two games with one card from the four-card hand.

Tomaru: When playing against each other, statistics on which cards the opponent played in the first round are also displayed. For example, the percentage of players who played goo in the first round is 90%, and so on. You can plan your strategy considering your remaining cards and your opponent’s tendency. However, since it is basically a rock-paper-scissors game, you don’t have to think too deeply about it, and you can play equally with anyone regardless of your playing record.

– How does blockchain come into play?

Horio: You can enjoy collecting cards to be used in the game through NFTs, which can be sold or purchased on “Jellyme”, an NFT marketplace of “MOOI Network” operated by a company of the Cocone Group. “JANKEN” is free to play, and players can earn medals and tokens (JGT) for gacha if they win. Cards have rarity and level, and collecting higher level cards increases the number of leagues you can participate in. There are also rankings within leagues.

Tomaru: Generally, Web3-based services tend to be considered a hurdle to play. Although “JANKEN” has some strategic elements, it is based on rock-paper-scissors-scissors, so anyone can play it easily.

– How long was the development period?

Horio: We had originally been warming up the idea of a service based on rock-paper-scissors, and the fact that Cocone was focusing on services incorporating Web3 and blockchain technology coincided with the development of JANKEN, which adds strategy and blockchain to rock-paper-scissors. It was only in early 2022 that we started working as a project, and at first there were only a few of us.
Tomaru: I joined in the summer of 2022, and since we released the open beta in December, the total development period was about one year. The rules are simple, but since this service allows players to enjoy real-time battles with anyone from around the world, and since it is necessary to support NFT of items, we had to work very hard on the system and infrastructure configuration and data design.

– How is the infrastructure and server configuration?

Tomaru: For ease of scale and availability, we use Amazon ECS, AWS Global Accelerator, and MongoDB Atlas (Figure 1). Even if there are tens of thousands of players in one country, if it becomes popular around the world, the number of players may exceed millions or tens of millions, and there will be many customers accessing the site from locations far from the region. In fact, the initial focus will be on Southeast Asia. In fact, at first we were thinking mainly of Southeast Asia, but once the open beta started, we were surprised to find that players were coming from all over the world, including Africa and Europe. We want players from all over the world to be able to play with us, so we do not limit match-ups by region. This means that your opponent could be on the other side of the world. Since they are physically quite far away from each other, we are focusing on making the game system as comfortable as possible as well as the infrastructure.
Horio: For players, losing a match is good stress, but they will be disillusioned if the game is interrupted or delayed due to communication or server problems, so we are taking all possible measures to ensure that players can fully enjoy the game.

– Can you tell us about some of the innovations in real-time competition?

Horio: Of course you can exchange card information while playing rock-paper-scissors, but you can also communicate using “emote” are emoji-like stamps that resemble chat messages. This allows players to play games with their opponents. This is also one of the most enjoyable aspects of JANKEN.

Tomaru: We use gRPC for communication. gRPC has four different communication methods, but this time we chose one that matches the characteristics of “JANKEN.

To be continued in Part 2.

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