Kokonotsuba

Kokonotsuba promotional image

Kokonotsuba is an open-source imageboard software originally developed by kuz for use on his websites, and as of December 2025, is only used by Heyuri, and formerly, NeoCafe and Nashi Kouen. Originally a fork of pixmicat, the software has since been modified so heavily that in 2021, kuz declared that it was its own independent software. It was originally released on March 14th, 2021 (9channel's 16th birthday), and was made open source on January 6th, 2023.

Kokonotsuba is likely the only registrationless BBS softwares still receiving regular content updates. Vichan, the former juggernaut software, used by many imageboards, and coming from a family of 8chan-derived or 8chan-associated imageboard software, has been largely unmaintained. It was handed over to Kuz in 2023, after its previous owner, Fredrick Brennan (of 8chan fame) decided it needed a new chief maintainer, as previous chiefs had gone AWOL. After kuz, it was placed in the hands of Angeleno, a former associate of kuz. Vichan now receives sporadic updates, and is alleged to be backdoored.

Features

Kokonotsuba has many features that make it quite unique, many ported from eastern imageboards, and many are novel inventions. A philosophy of emulating Japanese boards (such as futaba and 2channel) has lead Kokonotsuba to stand out. It also has many quality of life features not present in other BBS software. As of the recent (December 2025) multi-image update, Kokonotsuba is not only at feature parity with other BBS software, but could very well be said to surpass it in several metrics. Of course, this wiki is biased towards that idea.

Origin of the name

The name Kokonotsuba was originally suggested by an anonymous StrawberryHeaven user on November 7th, 2020, in a thread titled "New Software Name Suggestions Thread".

If you want to stick with "number of leaves on a plant" naming convention (e.g. Futaba (2 leaves), Yotsuba (4 leaves)), Kokonotsuba would be the "9 leaves" variation

According to KolymaNET's official website:

The name "Kokonotsuba" was chosen after the long-lasting tradition of naming imageboard software after the number of leaves on a plant (e.g. Futaba). "9 leaves" was chosen because of 9channel, the genesis of KolymaNET.

Why it was originally closed source

Before becoming open source, kuz had previously defended his choice of keeping the software closed source by saying:

You think just because somethings open source means people will contribute? [...] Kokonotsuba may not be the fastest but its definitely special, it has alot of cool features which make the boards that use it unique. The fact only a select few sites can use it contributes to those sites value in a special way. [...] If it was open source, it'd lose so much charm. Its ours. We can build it for ourselves.