lila-tablebase

Tablebase server for lichess.org, based on shakmaty-syzygy.

Usage

Usage: lila-tablebase [OPTIONS]

Options:
      --standard <STANDARD>          Directory with Syzygy tablebase files for standard chess
      --atomic <ATOMIC>              Directory with Syzygy tablebase files for atomic chess
      --antichess <ANTICHESS>        Directory with Syzygy tablebase files for antichess
      --antichess-tb <ANTICHESS_TB>  Directory with DTW tablebase files for antichess
      --gaviota <GAVIOTA>            Directory with Gaviota tablebase files

      --hot-prefix <HOT_PREFIX>      Directory with prefix files
      --mmap                         Use memory maps to read table files
      --advise-random                Set POSIX_FADVISE_RANDOM or MADV_RANDOM on table files
      --cache <CACHE>                Maximum number of cached responses [default: 20000]
      --bind <BIND>                  Listen on this socket address [default: 127.0.0.1:9000]
  -h, --help                         Print help (see more with '--help')

HTTP API

`GET /standard`

curl http://tablebase.lichess.ovh/standard?fen=4k3/6KP/8/8/8/8/7p/8_w_-_-_0_1

name	type	default	description
fen	string	required	FEN of the position. Underscores allowed.

{
  "dtz": 1, // dtz50'' with rounding or null if unknown
  "precise_dtz": 1, // dtz50'' (only if guaranteed to be not rounded) or null if unknown
  "dtm": 17, // depth to mate or null if unknown
  "dtw": null, // depth to antichess win or null if unknown
  "checkmate": false,
  "stalemate": false,
  "variant_win": false, // only in chess variants (atomic, antichess)
  "variant_loss": false, // only in chess variants
  "insufficient_material": false,
  "category": "win", // win, unknown, maybe-win, cursed-win, draw, blessed-loss, maybe-loss, loss
  "moves": [ // information about legal moves, best first
    {
      "uci": "h7h8q",
      "san": "h8=Q+",
      "dtz": -2,
      "precise_dtz": -2,
      "dtm": -16,
      "dtw": null,
      "zeroing": true,
      "checkmate": false,
      "stalemate": false,
      "variant_win": false,
      "variant_loss": false,
      "insufficient_material": false,
      "category": "loss" // loss, unknown, maybe-loss, blessed-loss, draw, cursed-win, maybe-win, win
    },
    // ...
  ]
}

`GET /standard/mainline`

curl http://tablebase.lichess.ovh/standard/mainline?fen=4k3/6KP/8/8/8/8/7p/8_w_-_-_0_1

name	type	default	description
fen	string	required	FEN of the position. Underscores allowed.

{
  "dtz": 1,
  "mainline": [ // dtz mainline or empty if drawn
    { "uci": "h7h8q", "san": "h8=Q+", "dtz": -2 },
    { "uci": "e8d7", "san": "Kd7", "dtz": 1 },
    { "uci": "h8h2", "san": "Qxh2", "dtz": -14 },
    { "uci": "d7c6", "san": "Kc6", "dtz": 13 },
    { "uci": "h2e5", "san": "Qe5", "dtz": -12 },
    { "uci": "c6b6", "san": "Kb6", "dtz": 11 },
    { "uci": "g7f6", "san": "Kf6", "dtz": -10 },
    { "uci": "b6a6", "san": "Ka6", "dtz": 9 },
    { "uci": "e5b2", "san": "Qb2", "dtz": -8 },
    { "uci": "a6a5", "san": "Ka5", "dtz": 7 },
    { "uci": "f6e5", "san": "Ke5", "dtz": -6 },
    { "uci": "a5a4", "san": "Ka4", "dtz": 5 },
    { "uci": "e5d4", "san": "Kd4", "dtz": -4 },
    { "uci": "a4a5", "san": "Ka5", "dtz": 3 },
    { "uci": "d4c5", "san": "Kc5", "dtz": -2 },
    { "uci": "a5a4", "san": "Ka4", "dtz": 1 },
    { "uci": "b2a2", "san": "Qa2#", "dtz": -1 }
  ],
  "winner": "w" // (w) white, (b) black, (null) draw
}

Claims draw by 50-move rule as soon as possible and ends the mainline. Error 404 if not a tablebase position or required tables not present.

`GET /atomic`

`GET /antichess`

Acknowledgements

Thanks to Ronald de Man for his Syzygy endgame tables. Thanks to Bojun Guo for generating and sharing 7-piece tables.

License

lila-tablebase is licensed under the GNU Affero General Public License 3.0 (or any later version at your option). See the COPYING file for the full license text.

lichess-org / lila-tablebase