Go · Baduk · Weiqi

A Go board that feels every move.

Hoshi is a free desktop app for playing and studying Go. A beautiful board, KataGo judging every move live, joseki guidance in every corner, cinematic effects when you find the best move, and lo-fi music that heats up with your streaks.

Get Hoshi Source on GitHub
  • Windows · macOS · Linux
  • KataGo included
  • Play on OGS
  • Joseki trainer
  • GTP engines
  • English · Español
An opening is being played…

Features

Everything you need at the board.

Play friends on one screen, take on KataGo or any GTP engine, review your games, or take on the world on OGS.

Hoshi with the analysis panel: win rate, score graph and the rating of the last move
  • ◎

    Live AI analysis

    KataGo runs in the background from the moment Hoshi opens and rates every move: best, excellent, good, inaccuracy, mistake or blunder, with points lost.

  • ▦

    Territory at a glance

    See secure and potential territory and the estimated score, from Hoshi's own estimator or KataGo's ownership map.

  • ▤

    Your game libraryNew

    Every game you play is kept. Open one later and step through it: KataGo judges each move again, with all its effects and music.

  • ❖

    SGF editor

    Open and save SGF files, explore variations in a game tree, add comments, marks and setup stones.

Joseki

Never forget a joseki again.

Study the standard corner sequences while you play, then drill them until they stick.

Joseki continuations shown as coloured discs in two corners, with the legend in the sidebar
Joseki on the boardPlace a stone and Hoshi looks up that corner in the OGS Joseki Explorer and in your own library. The known answers appear as discs, the rating of your last move sits on top, and the explorer's comments show in the sidebar.
The joseki trainer on the main board, with the line list and family filter
The trainerCtrl+J turns the main board into a practice board; your game waits underneath. Place every stone of the line: a cross marks a miss, a circle shows the answer after two.

01Spaced repetition

Six Leitner boxes, from ten minutes to a month. A perfect run waits longer; a mistake comes back soon.

02Pick what to study

Filter by 4-4, 3-4, 3-3, 4-5 or 3-5, choose a line from the list, or let Hoshi pick what is due.

03Endless lines

“New line from OGS” follows only ideal and good moves of the Joseki Explorer. Import SGF collections or record lines from your own board.

Boards & stones

Wood you can almost smell.

Every goban, stone and background is rendered by Hoshi itself: straight-grain kaya, clam shell with its growth lines, slate, yunzi, glass and jade. Each stone keeps its own look on its point, like a real set.

Gobans

Kaya, straight grain
Kaya, flat grain
Shin-kaya
Katsura
Bamboo
Walnut

Stones

Clam shell and slate
Yunzi
Glass
Matte ceramic
Jade and obsidian

Mix them with any theme

Each theme comes with its own set. In Preferences → Board & stones, pick any goban, stones and background and see them live before you play.

Indigo sashiko Walnut table Slate Charcoal linen Bamboo blind Night sky, ink mist, zen sand, washi, tatami
Preferences: Board & stones, with a live preview and pickers for goban, stones and background

Effects

Find the move that matters. The board notices.

Every effect is drawn and synthesised by Hoshi itself — no stock footage, no samples.

Glowing cracks around a stone
The move that mattersThe best move at a turning point: a cinematic boom, shockwaves and molten cracks.
Cooled cracks in the wood
…and its markThe fractures cool into the wood, then fade.
Captured stones shattering
CapturesStones shatter in a wave, with a crisp crack and a chime.
A weak white group with a blue halo and a lost black stone with a red glow
Weak groupsA quiet halo: blue while a group is unsettled or weak, a slow red glow when it is in real danger.

Themes

Pick the room you play in.

Zen garden theme with territory shown
Zen gardenRaked sand, shin-kaya and clam-shell stones — shown here with the territory estimate.
Ink and gold theme
Ink and goldA sumi-e nocturne of drifting ink and seal red, on flat-grain kaya.
Warm minimal theme
Warm minimalWashi paper, katsura wood, matte ceramic stones and terracotta.
Night sky theme
Night skyHoshi means “star”: a midnight sky with twinkling stars and glass stones.

Music

A soundtrack that plays along.

Six layers composed in code join one by one as you string good moves together. A blunder stops the tape. Time cools it back down.

  • Warm electric piano and vinyl crackle
  • Bass and a soft kick
  • Swung drums
  • Plucked arpeggio with echo
  • Pumping chords, claps and a bright lead
  • Overdrive: four-on-the-floor, rolling bass, fills

Demo: calm, then a streak of strong moves from 0:16 and a blunder at 1:10… you'll hear it.

正

Fair play built in

During live games on OGS, KataGo stays off — OGS forbids AI help while you play. The joseki hints and the trainer are off too. The effects and the music follow the fight on the board instead (contact, liberties, captures), and Hoshi's own quick territory estimate is there. Every game is kept in your library, where the AI review — with all its effects — is waiting after the game.

Get Hoshi

Download and play.

Installers for Windows, macOS and Linux, built with Avalonia. Nothing else to install: .NET comes inside. Once installed, Hoshi updates itself in one click and only downloads what changed.

Download

Free · open source · other systems below

Windows

Windows 10 or 11. Run the installer: Hoshi appears in the Start menu and on the desktop, and updates itself.

x64ARM64

First launch: if SmartScreen warns about an unknown publisher, choose “More info” → “Run anyway”. Portable: x64 · ARM64

macOS

macOS 12 or later. Open the .pkg and follow the steps: Hoshi goes to Applications and updates itself.

Apple SiliconIntel

Hoshi is not notarized by Apple yet: if macOS refuses the .pkg, right-click it → Open, or allow it in System Settings → Privacy & Security. Portable: Apple Silicon · Intel

Linux

Any recent x64 or ARM64 distribution. One file: make it executable and run it — it updates itself.

x64ARM64
chmod +x HoshiGo-linux-x64.AppImage
./HoshiGo-linux-x64.AppImage

If it does not start, install FUSE 2 (sudo apt install libfuse2). Music needs PulseAudio/PipeWire (pacat) or ALSA (aplay). Classic archive: x64 · ARM64

KataGo included

The Windows and Linux downloads come with KataGo and a quick network, ready from the first start. On a Mac, run brew install katago and Hoshi finds it. Stronger networks can be picked in Preferences → Analysis.

Build from source

With the .NET 10 SDK:

git clone https://github.com/BuddhaCodes/BadukDana.git
cd BadukDana
dotnet run --project src/Hoshi.App -c Release

Hoshi is free, and will stay free.

It is made in spare time, with love for the game. If it brings you good games and you would like to help it grow — signing the Windows build, more boards, more study tools — you can support it with a donation on PayPal. Entirely optional; thank you either way.

PayPal isn't available where I live, so donations go to a trusted collaborator, Carlos Fernandez — the name you'll see on PayPal.

Support Hoshi ♥