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About Misaka

Misaka is the current kernel used in ToaruOS, created by Kevin Lange.

It was introduced into the mainline ToaruOS codebase on May 31st 2021 under a commit (b35f7ac8c94f7c5dde8b9755d94c010a32ba5a28) named "misaka: initial merge" and during the 1.99.1-1.99.10 beta releases from June 15th to December 1st 2021 before having a stable release on December 12th 2021 alongside ToaruOS 2.0. Misaka was built to replace the "toaru32" kernel from the pre-1.99.x days of ToaruOS as Kevin has said he felt that the old kernel "was a source of personal embarrassment" for him.

"Through out the project, ToaruOS has also attracted quite a few beginner OS developers who have tried to use it as a reference. ToaruOS's kernel, however, was a source of personal embarrassment for me, and in April 2021, after a long hiatus, I began work on a new one. The result was Misaka: a new 64-bit, SMP-enabled kernel. Misaka was merged in May and started the 1.99 series of beta releases leading up to ToaruOS 2.0."

The kernel is named after the character Misaka Mikoto1 from the light novel/anime series "Toaru Kagaku no Railgun" (A Certain Scientific Railgun), which is where ToaruOS gets its name from. The "Toaru" part of the name is Japanese for "A Certain…" or "Some Such...".

Misaka is built for x86_64 and AARCH64 and has Symmetric Multi-Processing capabilities.

A short history of Misaka's development

Development of Misaka started on September 12th 2015. The first commit (11270d6de5b2387bd659d8a24f4253f4f545d760) was on the same day, named "Hello world". This commit only featured a README before the next commit hours later which added kernel code.

Misaka was mentioned at Kevin's "ToaruOS at 5 Years: A Closer Look at a Hobby OS" talk on October 16th 2015 (uploaded on October 30th 2015) on the "Future" slide under Now: "Misaka" x86-64 kernel project. The presentation itself can be found here on toaruos.org.

Development heavily slowed down after September 22nd 2015 after a commit (8897ae1d1935e25fb25c5471df17ea54350e8b16) named "**** it, we're doing C11". Misaka had no activity until the commits on October 22nd 2018 which it would then go back into a state of no activity.

May 23rd 2019 is the day of the last commit (737cb127b94bf46931e657cf321ba28d9ab3731d) made to Misaka's "old-master" branch until April 13th 2021 when a new branch was made which became master with commit (f354476496ceb9df9104ad99e4ab10e2677148bd) named "Hello, world.".

This is the start of what Misaka is today. From April 13th 2021 until May 31st 2021, Kevin would keep on committing to Misaka until the eventual merge commit (b35f7ac8c94f7c5dde8b9755d94c010a32ba5a28) "misaka: initial merge".

Misaka's repo on the "toaruos" organization was then archived on the same day.

  1. As far I (NerdNextDoor) know, this is mainly an assumption.

    Kevin has stated that Toaru Kagaku no Railgun was an inspiration for the name ToaruOS, but no exact link that I can remember to why the kernel is named Misaka.

    It would make sense as he named his interpreter language Kuroko seemingly after Kuroko Shirai from the same series. (See https://github.com/kuroko-lang/kuroko. Also, Index or Railgun? Kevin also stated he liked Railgun more in the now inaccessible ToaruOS wiki. I honestly can't remember.)

    He also codenamed ToaruOS 0.14.0 "Kuroko" along with a picture of Kuroko Shirai. (See https://github.com/klange/toaruos/releases/tag/v0.14.0.)

    This claim is unverified but I believe that this is the reason why the new kernel is named Misaka as there is a lot of evidence to support this idea. ↩