Dev Builds » 20260415-1815

Use this dev build

NCM plays each Stockfish dev build 20,000 times against Stockfish 15. This yields an approximate Elo difference and establishes confidence in the strength of the dev builds.

Summary

Host Duration Avg Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo
ncm-dbt-01 06:41:11 583163 3998 1765 353 1880 +128.23 ± 4.47 0 24 571 1372 32 +294.84 ± 14.21
ncm-dbt-02 06:41:21 585640 4004 1744 361 1899 +125.15 ± 4.52 0 32 583 1359 28 +286.02 ± 14.08
ncm-dbt-03 06:40:45 585165 4000 1762 364 1874 +126.77 ± 4.54 0 30 575 1362 33 +289.68 ± 14.18
ncm-dbt-04 06:40:41 566369 4000 1748 372 1880 +124.6 ± 4.46 0 26 598 1350 26 +284.85 ± 13.87
ncm-dbt-05 06:41:37 580943 3998 1740 347 1911 +126.34 ± 4.51 0 33 567 1372 27 +290.23 ± 14.29
20000 8759 1797 9444 +126.22 ± 2.01 0 145 2894 6815 146 +289.1 ± 6.31

Test Detail

ID Host Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo CLI PGN
464471 ncm-dbt-02 586816 4 2 1 1 +88.51 ± 137.63 0 0 1 1 0 +190.5 ± 634.21
464470 ncm-dbt-05 579372 498 220 37 241 +133.93 ± 12.1 0 3 62 182 2 +320.38 ± 43.76
464469 ncm-dbt-01 584706 498 220 38 240 +133.13 ± 13.12 0 4 65 174 6 +306.03 ± 42.72
464468 ncm-dbt-04 566493 500 213 56 231 +112.91 ± 12.13 0 3 87 160 0 +256.44 ± 36.38
464467 ncm-dbt-03 584748 500 223 40 237 +133.34 ± 12.89 0 2 70 171 7 +304.07 ± 40.91
464466 ncm-dbt-02 587113 500 216 34 250 +132.54 ± 12.32 0 4 62 182 2 +315.35 ± 43.81
464465 ncm-dbt-05 583489 500 210 44 246 +119.89 ± 12.98 0 5 77 165 3 +270.57 ± 39.07
464464 ncm-dbt-04 567007 500 221 50 229 +123.81 ± 12.73 0 4 74 169 3 +282.94 ± 39.86
464463 ncm-dbt-01 585126 500 218 47 235 +123.81 ± 13.63 0 8 67 171 4 +280.42 ± 42.05
464462 ncm-dbt-03 587409 500 225 34 241 +139.81 ± 11.84 0 2 58 187 3 +339.63 ± 45.29
464461 ncm-dbt-02 586435 500 215 51 234 +118.33 ± 12.44 0 2 85 160 3 +265.78 ± 36.75
464460 ncm-dbt-05 578465 500 215 49 236 +119.89 ± 13.16 0 4 81 160 5 +265.78 ± 37.95
464459 ncm-dbt-01 581236 500 220 43 237 +128.55 ± 12.04 0 1 74 172 3 +298.62 ± 39.56
464458 ncm-dbt-04 565272 500 226 40 234 +135.76 ± 12.42 0 2 65 178 5 +318.25 ± 42.59
464457 ncm-dbt-02 585590 500 216 47 237 +122.24 ± 13.12 0 4 78 163 5 +273.0 ± 38.74
464456 ncm-dbt-03 585337 500 214 40 246 +126.17 ± 13.06 0 5 70 171 4 +288.06 ± 41.11
464455 ncm-dbt-05 584537 500 222 42 236 +130.94 ± 12.37 0 4 64 180 2 +309.64 ± 43.08
464454 ncm-dbt-01 580696 500 225 44 231 +131.74 ± 12.34 0 0 75 169 6 +301.33 ± 39.1
464453 ncm-dbt-03 583321 500 219 56 225 +117.55 ± 13.0 0 4 83 159 4 +261.07 ± 37.44
464452 ncm-dbt-02 586520 500 207 41 252 +119.89 ± 12.61 0 4 78 166 2 +273.0 ± 38.74
464451 ncm-dbt-04 567561 500 215 46 239 +122.24 ± 12.76 0 4 76 167 3 +277.93 ± 39.29
464450 ncm-dbt-05 582736 500 225 46 229 +130.14 ± 13.16 0 5 66 174 5 +298.62 ± 42.41
464449 ncm-dbt-01 581652 500 218 41 241 +128.55 ± 12.82 0 4 69 173 4 +295.94 ± 41.39
464448 ncm-dbt-03 584495 500 220 37 243 +133.34 ± 12.89 0 4 64 177 5 +309.64 ± 43.08
464447 ncm-dbt-02 582569 500 219 39 242 +130.94 ± 12.56 0 3 68 175 4 +304.07 ± 41.65
464446 ncm-dbt-04 568156 500 224 46 230 +129.35 ± 12.8 0 3 71 171 5 +295.94 ± 40.69
464445 ncm-dbt-05 579537 500 220 57 223 +117.55 ± 12.46 0 1 89 156 4 +261.07 ± 35.67
464444 ncm-dbt-01 584159 500 215 50 235 +119.11 ± 12.62 0 3 82 162 3 +268.17 ± 37.61
464443 ncm-dbt-02 586731 500 223 44 233 +130.14 ± 12.39 0 4 65 179 2 +306.84 ± 42.73
464442 ncm-dbt-03 584034 500 215 40 245 +126.97 ± 12.85 0 6 65 177 2 +295.94 ± 42.75
464441 ncm-dbt-04 567680 500 218 47 235 +123.81 ± 13.1 0 4 76 165 5 +277.93 ± 39.29
464440 ncm-dbt-05 580945 500 214 31 255 +133.34 ± 12.89 0 6 58 183 3 +315.35 ± 45.33
464439 ncm-dbt-04 562651 500 217 38 245 +130.14 ± 12.19 0 4 64 181 1 +309.64 ± 43.08
464438 ncm-dbt-01 583614 500 227 54 219 +125.38 ± 13.25 0 4 75 165 6 +280.42 ± 39.57
464437 ncm-dbt-03 585506 500 215 62 223 +109.83 ± 12.34 0 3 92 154 1 +245.2 ± 35.25
464436 ncm-dbt-02 584916 500 224 51 225 +125.38 ± 13.43 0 6 70 169 5 +282.94 ± 41.13
464435 ncm-dbt-01 584117 500 222 36 242 +135.76 ± 10.91 0 0 64 186 0 +333.32 ± 42.66
464434 ncm-dbt-04 566138 500 214 49 237 +119.11 ± 12.62 0 2 85 159 4 +265.78 ± 36.75
464433 ncm-dbt-05 578465 500 214 41 245 +125.38 ± 12.89 0 5 70 172 3 +288.06 ± 41.11
464432 ncm-dbt-02 584076 500 222 53 225 +122.24 ± 13.3 0 5 76 164 5 +273.0 ± 39.35
464431 ncm-dbt-03 586477 500 231 55 214 +127.76 ± 13.39 0 4 73 166 7 +285.49 ± 40.16

Commit

Commit ID 5f3dcb92ee097f3f1c3656570c4d1a473e95e3aa
Author J. Oster
Date 2026-04-15 18:15:36 UTC
Simplify stalemate detection in qsearch. Conditions for no pawn pushes, non-pawn material and last captured piece are already such restrictive that we don't need to artificially set checkers bitboard for legal move generation. Also moving the check for available pawn pushes at first place, as it should already filter about 90% of cases. Passed STC and LTC non-regression tests. LLR: 2.96 (-2.94,2.94) <-1.75,0.25> Total: 171232 W: 44202 L: 44131 D: 82899 Ptnml(0-2): 466, 18809, 47023, 18824, 494 https://tests.stockfishchess.org/tests/view/69d3623b61a12cebe17ededa LLR: 2.94 (-2.94,2.94) <-1.75,0.25> Total: 55662 W: 14424 L: 14247 D: 26991 Ptnml(0-2): 38, 5479, 16609, 5678, 27 https://tests.stockfishchess.org/tests/view/69d64cada07a818b0a25f95e And also neutral on 10k fixed games test with custom stalemate book. Elo: 0.24 ± 0.9 (95%) LOS: 69.9% Total: 10000 W: 4681 L: 4674 D: 645 Ptnml(0-2): 0, 87, 4819, 94, 0 nElo: 1.81 ± 6.8 (95%) PairsRatio: 1.08 https://tests.stockfishchess.org/tests/view/69d7e4183ca80bdf151d43b8 closes https://github.com/official-stockfish/Stockfish/pull/6715 Bench: 2984258
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