Welcome to the Kaastle dev log
Why we are making a game where your answers are your army, and what this log will cover.
Kaastle is a game for learning music. You play a note on your guitar or bass, the game hears it, and a soldier marches out to hold your keep. Miss, and the enemy gets the squad instead. Every right answer is a small victory you can see.
We started on 13 September 2026 with a single idea: a note on the fretboard summons a defender. A little over a month and more than a thousand commits later, the game has an army of historical cards, a memory model that knows which notes you are about to forget, a battle report that grades you like a school would, and several ways to play. We want to tell you how we got here, and why.
What we care about
Practice that is real. The fretboard is learned with your hands and ears, not by clicking. Kaastle listens through your microphone or audio interface, so the note you play on your own instrument is the answer. You can tap the on-screen fretboard too, but the instrument is the point.
Learning built on how memory works. Every note you meet has its own memory record. The game schedules it for review just as it is starting to fade, which is what spaced-repetition research says makes things stick. We grade honestly: a slow, inaccurate win is not an A, even on Easy.
Fun that earns its place. The battle is not decoration. Right answers field your deck's cards in order, streaks call in the elites, and morale, range and terrain all matter. If the fight is good, you come back to practise tomorrow.
Worlds built with care. The armies come from many places and times: Spartans and Persians at Thermopylae, Song generals and the outlaws of Liangshan Marsh, Romans, Vikings, samurai, Joseon gunners, Mongol riders and many more. We read about them before we draw them, give their names in their own scripts, and try to be truthful to what each card depicts.
What this log is
This is where we explain our decisions to you, the players. Most of the posts below are written in retrospect: we went back through our commit history and design notes and wrote down what we built and why, dated to when the work happened. From now on, new posts will come as the work does.
The log is in English and 简体中文. Use the switch at the top of the page, or follow along by RSS.
Thank you for playing, and for practising. Find your note. Hold your ground.