Founder · launching October 2026
Fluentei — Japanese through the songs you sing
fluentei.com.br ↗Understand the Japanese songs you sing. Tap any word in the lyrics for its meaning, translation and context.
Songs come with furigana and romaji; graded readings come narrated, lighting up word by word. Review then brings back the words you met there, spaced over time, one song or reading at a time. Games keep the habit: Kyogi Karuta for kana and vocabulary (plus a 20-poem mode), a pixel RPG for kana, and Nekomachi, a cat neighbourhood your reviews keep fed. And Ginga, the astronaut mascot, chats with you in Japanese at your level, with furigana and replies you can tap.
On Fluentei I own everything: product, design and code. It runs on Cloudflare Workers, with PostgreSQL on Neon and payments through Stripe. SudachiPy analyses the Japanese, so the grammar comes from a parser, not from a model's guess. AI explains and chats, inside limits I set. Before opening it, I load-tested the whole thing to hold the launch.
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