Mikio Hirabayashi gave us an exclusive interview. He is the author and maintainer of Tokyo Cabinet, a free (open source) library of routines for managing a database.
What is the story behind Tokyo Products? When did you start developing them and why?
When I started to develop Tokyo Products, I was already working at mixi which was the largest SNS site in Japan. I wrote and maintained almost all search services there. I also wrote the search engine 'Hyper Estraier' (HE) which was released as an open source software. As HE used 'Quick DataBase Manager' (QDBM) to handle inverted index of documents, I had complaints about its performance. In early 2007, while I was developing a search service, I decided to write a new database library to handle inverted index more efficiently. I've been completing it for several months and then I released it as 'Tokyo Cabinet' (TC). The B+ tree mechanism of TC was designed to handling inverted index.
How many companies use Tokyo Products? How many users do they have?
As far as I know, tens companies use Tokyo Cabinet and Tokyo Tyrant in their commercial products or services. As I've been promoted my products in Japanese, most of the users are in Japan. Except for the direct users: a lot of open source product use TC and TT, such as "kumofs", "flare", "lightcloud", "cloudkit" and "mutt".
Why did you choose to release your software with a free license?
There were many reasons. The most important one was to improve quality. By publishing the source code, many users can read it and give me a lot of valuable feedbacks. Without them, my code would have never reached the stable version. The second important one was to work at home. Mixi admitted staff members to release reusable software as open source products if possible. All the codes produced at mixi were confidential and could not be brought back home of course. However, open source products could be brought back home. mixi was generous to allow staff members to have their copyrights of such open source products. It contributed to increase our motivation.
From your point of view, what brings the free software distribution to Tokyo Products? And how do you contribute yourself to the free software?
I think that company culture is very important for us to develop open source software. The ideal situation is that programs developed on duty can be released as open source products and it also contributes to the business. I was lucky to work in such situation. As for as I see, web service companies tend to have relatively free culture. I released QDBM, Hyper Estraier, Tokyo Cabinet, Tokyo Tyrant, Kyoto Cabinet and they combined the two of business contribution and free software contribution, I think.
Do you think that an open source equivalent of Google Search Engine could be created?
It seems very difficult. Google Search Engine is not a mere software. It requires not only very high technologies, but also hardware, facilities, administration staff, and sustainable business model to raise money to support them.
What do you think about TIO Libre definition ?
I read TIO Libre definition and I found it interesting. I wish I could see a world where a lot of services conforming to TIO Libre definition were thriving.
Interview by Elodie Pot - writer
(c) 2010 TioNews
Follow us on Twitter: @tio_news