Credits and licences
The game
Bakahatsu is free and its code is open, under the MIT licence, © 2026 yanis-san. You may use, modify and share it as long as you keep this notice.
Your data
When a game ends, the server stores the nickname chosen, the words played, the scores, the interface language and a random identifier created by your browser (never shown to other players). Nothing else: no IP address, no tracking cookie, no information about your device. This data is used to improve the game and to link your history to your account if you create one. It is neither sold nor shared. If you clear the site’s data in your browser you start over with a new identifier: your past games are no longer linked to you.
Dictionary
Words and their meanings (English, and French when JMdict provides it) come from the JMdict file, © Electronic Dictionary Research and Development Group (EDRDG). The game dictionary is a filtered, reformatted version of that file; the filtering rules are documented in the repository.
Kanji and levels
The readings and meanings of the kanji come from KANJIDIC2 (EDRDG, CC BY-SA 4.0). The JLPT no longer publishes official lists: the levels N5 to N1 follow Jonathan Waller’s lists (CC BY), so they are only indicative.
Example sentences
Example sentences and their translations come from the Tatoeba project and its contributors, under the CC BY 2.0 FR licence. They are attached to the words through the JMdict example file. No translation is machine generated.
Fonts
Shippori Mincho, Zen Maru Gothic, Zen Kaku Gothic New and JetBrains Mono, under the SIL Open Font License 1.1, self-hosted through Fontsource.
Software
Svelte and SvelteKit (MIT), WanaKana (MIT) for romaji to kana conversion, FastAPI, msgspec and jaconv.
Artwork and sounds
The mascot Exupulojon, the avatars and the icons are drawn for Bakahatsu. Sounds are synthesised in the browser: no third-party audio files.