melune is a desktop app for adults who want to actually speak the language they're learning. You sit down for a real conversation in your target language, then afterwards you read careful notes on what you said — what was right, what wasn't, and what to try the next time.
The unit of practice is a conversation. You sit down for fifteen minutes, speak with the tutor in your target language, and end the session. The tutor listens patiently, asks follow-ups, and remembers what you've said in previous sessions — your job, your family, the trip you took last month, the show you're watching.
Afterwards, a written replay opens. Each of your turns has any grammatical corrections attached inline, with a short explanation of why. Pronunciation notes use IPA and sit alongside the audio you actually produced. New vocabulary the tutor used gets queued for review later.
Over time, melune builds a picture of where you tend to slip — which case you keep getting wrong, which vowel you keep collapsing — and the next day's session is shaped around that. The recommendation comes with its reasoning visible: which categories it's targeting and why it picked them.
These shape almost every design decision in the app. They're more useful than a feature list because they explain what gets left out, too.
Spoken practice is the central activity. Drills, vocabulary, and reading exist to support what you do when you're actually talking.
Corrections explain why, not just what. The proficiency estimate shows its confidence. When the curriculum picks today's session, the reasoning is right there.
No streaks, no XP, no badges, no mascot. Stats are for reflection, not pressure. Long-form feedback is treated like prose, not chat.
Honest snapshot of where the build is. Items marked working are wired end-to-end in internal alpha; in progress means the engine is done but the UI is being rebuilt; planned means designed but not yet started.
A few decisions worth flagging — places where the literature pushed back against what would have been easier or more profitable to ship.
Pronunciation feedback is reserved for scripted practice. Shadowing, drills, and read-aloud get phoneme-level analysis with IPA. Free conversation, scenarios, and curriculum sessions don't. The L2 pronunciation literature is consistent that instruction transfers to controlled production but not to spontaneous speech, and forced-aligners degrade on spontaneous audio. So melune spends pronunciation effort where it actually pays off, and keeps conversation focused on grammar, vocabulary, pragmatics, and fluency.
Sessions are capped near fifteen minutes. Distributed practice beats marathon practice for durable gains across syntax, morphology, fluency, and pronunciation. Four to six short sessions per week is the research-aligned shape. The session cap is treated as a learning feature, not a platform limit — and the same logic will shape any future subscription tier.
The level label moves slowly. An internal proficiency estimate updates after every session, because that's what the curriculum needs to plan tomorrow. But the level you see is a slower, hedged display — with a confidence band and the evidence behind it shown — so a single noisy session doesn't shove your level around.
macOS first. melune is built natively in SwiftUI for the desktop. Sessions happen at a real keyboard with real audio hardware, which is where careful practice tends to happen anyway. An iOS companion will follow.
Bring your own API key, for now. The first builds connect directly to Google's Gemini API using a key you provide. At fifteen minutes of conversation a day plus a few drill or shadowing sessions a week, that runs to roughly $11–14 a month at current API prices. A managed-connection subscription will follow, so you won't have to handle the key yourself.
Two languages at the start. German and Korean are the initial target languages — chosen because they exercise different parts of the architecture (case morphology in one, speech levels and an honorific system in the other). More languages come once those two feel right.
A small, careful release. The first public build will go out to a small group, not a wide launch. There will be a way to put your name down before that happens — it's not wired up yet.