Dev Builds » 20260519-1635

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 06:44:06 583710 4010 1792 300 1918 +135.79 ± 4.35 0 18 512 1440 35 +320.22 ± 15.02
ncm-dbt-02 06:42:22 586557 4000 1790 314 1896 +134.55 ± 4.5 0 25 516 1417 42 +313.19 ± 14.98
ncm-dbt-03 06:43:05 584515 3994 1758 327 1909 +130.26 ± 4.4 0 17 565 1382 33 +301.37 ± 14.26
ncm-dbt-04 06:42:48 567344 3996 1783 329 1884 +132.49 ± 4.43 0 23 531 1411 33 +309.09 ± 14.76
ncm-dbt-05 06:42:16 582645 4000 1764 333 1903 +130.05 ± 4.4 1 17 562 1390 30 +302.01 ± 14.3
20000 8887 1603 9510 +132.62 ± 1.97 1 100 2686 7040 173 +309.08 ± 6.55

Test Detail

ID Host Base NPS Games WLD Standard Elo Ptnml(0-2) Gamepair Elo CLI PGN
469946 ncm-dbt-01 584537 10 5 2 3 +107.43 ± 84.35 0 0 2 3 0 +240.65 ± 570.11
469945 ncm-dbt-03 584832 494 209 40 245 +123.85 ± 12.63 0 2 78 163 4 +280.43 ± 38.54
469944 ncm-dbt-04 568832 496 227 37 232 +140.24 ± 13.32 0 2 64 172 10 +319.57 ± 42.94
469943 ncm-dbt-05 582778 500 221 46 233 +126.97 ± 12.66 0 3 73 170 4 +290.66 ± 40.08
469942 ncm-dbt-02 586350 500 227 38 235 +138.18 ± 11.48 0 1 61 186 2 +336.46 ± 43.96
469941 ncm-dbt-01 582318 500 220 39 241 +131.74 ± 13.12 0 3 70 170 7 +298.62 ± 41.01
469940 ncm-dbt-03 582068 500 225 42 233 +133.34 ± 12.49 0 2 68 175 5 +309.64 ± 41.56
469939 ncm-dbt-04 567047 500 223 40 237 +133.34 ± 11.88 0 1 68 178 3 +315.35 ± 41.44
469938 ncm-dbt-05 585928 500 219 37 244 +132.54 ± 12.52 0 2 69 174 5 +306.84 ± 41.23
469937 ncm-dbt-01 581943 500 228 39 233 +138.18 ± 12.93 0 3 62 178 7 +321.19 ± 43.77
469936 ncm-dbt-02 586816 500 219 33 248 +135.76 ± 12.81 0 7 52 189 2 +327.18 ± 47.79
469935 ncm-dbt-03 586393 500 224 41 235 +133.34 ± 12.09 0 1 69 176 4 +312.48 ± 41.11
469934 ncm-dbt-04 567958 500 227 46 227 +131.74 ± 12.74 0 4 65 177 4 +306.84 ± 42.73
469933 ncm-dbt-01 583028 500 232 32 236 +147.19 ± 11.92 0 1 54 189 6 +359.68 ± 46.95
469932 ncm-dbt-02 586350 500 219 40 241 +130.14 ± 12.78 0 4 67 175 4 +301.33 ± 42.04
469931 ncm-dbt-05 580572 500 217 40 243 +128.55 ± 12.24 0 2 72 173 3 +298.62 ± 40.29
469930 ncm-dbt-03 585421 500 223 41 236 +132.54 ± 12.32 0 2 68 176 4 +309.64 ± 41.56
469929 ncm-dbt-04 566454 500 226 45 229 +131.74 ± 12.54 0 3 67 176 4 +306.84 ± 41.99
469928 ncm-dbt-05 585464 500 229 36 235 +141.44 ± 12.2 0 2 58 185 5 +339.63 ± 45.29
469927 ncm-dbt-02 585000 500 212 45 243 +120.67 ± 13.15 0 5 77 164 4 +270.57 ± 39.07
469926 ncm-dbt-01 582193 500 213 41 246 +124.6 ± 11.94 0 1 78 169 2 +288.06 ± 38.42
469925 ncm-dbt-03 584369 500 221 46 233 +126.97 ± 13.04 0 5 69 172 4 +290.66 ± 41.43
469924 ncm-dbt-04 566336 500 219 45 236 +126.17 ± 12.49 0 4 70 174 2 +293.29 ± 41.07
469923 ncm-dbt-05 579992 500 233 50 217 +133.34 ± 12.49 0 1 71 172 6 +306.84 ± 40.47
469922 ncm-dbt-01 585000 500 228 46 226 +132.54 ± 11.91 0 3 63 183 1 +318.25 ± 43.39
469921 ncm-dbt-02 586181 500 229 43 228 +135.76 ± 12.42 0 2 65 178 5 +318.25 ± 42.59
469920 ncm-dbt-03 585801 500 223 36 241 +136.56 ± 11.76 0 0 67 179 4 +324.16 ± 41.61
469919 ncm-dbt-04 567799 500 214 46 240 +121.45 ± 12.2 0 2 80 166 2 +277.93 ± 38.02
469918 ncm-dbt-01 585928 500 220 37 243 +133.34 ± 12.29 0 2 67 177 4 +312.48 ± 41.9
469917 ncm-dbt-05 580821 500 218 41 241 +128.55 ± 13.01 1 3 67 176 3 +301.33 ± 42.04
469916 ncm-dbt-02 586731 500 233 37 230 +143.89 ± 12.71 0 3 55 185 7 +342.85 ± 46.64
469915 ncm-dbt-03 585548 500 217 33 250 +134.15 ± 12.86 0 3 66 175 6 +309.64 ± 42.33
469914 ncm-dbt-04 566928 500 225 36 239 +138.18 ± 12.33 0 3 59 184 4 +330.23 ± 44.94
469913 ncm-dbt-02 588132 500 220 35 245 +134.95 ± 12.84 0 0 74 167 9 +304.07 ± 39.39
469912 ncm-dbt-05 580821 500 214 34 252 +130.94 ± 12.17 0 2 69 176 3 +306.84 ± 41.23
469911 ncm-dbt-01 584664 500 221 33 246 +137.37 ± 12.56 0 3 61 181 5 +324.17 ± 44.15
469910 ncm-dbt-04 567403 500 222 34 244 +137.37 ± 12.56 0 4 58 184 4 +327.18 ± 45.37
469909 ncm-dbt-03 581693 500 216 48 236 +121.45 ± 12.2 0 2 80 166 2 +277.93 ± 38.02
469908 ncm-dbt-05 584790 500 213 49 238 +118.33 ± 12.06 0 2 83 164 1 +270.57 ± 37.24
469907 ncm-dbt-02 586901 500 231 43 226 +137.37 ± 13.34 0 3 65 173 9 +312.48 ± 42.67
469906 ncm-dbt-01 583782 500 225 31 244 +142.25 ± 11.73 0 2 55 190 3 +349.43 ± 46.59

Commit

Commit ID c67c1ec603d22202cc35e1ddfa685a705d9b4b3c
Author Robert Nurnberg @ elitebook
Date 2026-05-19 16:35:23 UTC
[bugfix] Guard is_decisive() to avoid assert triggers This PR fixes an oversight in #6818. At least in multithreaded searches the TT scores can be corrupted, and accessing them is racy. Passed non-reg STC: LLR: 2.93 (-2.94,2.94) <-1.75,0.25> Total: 61792 W: 15609 L: 15428 D: 30755 Ptnml(0-2): 134, 6534, 17373, 6727, 128 https://tests.stockfishchess.org/tests/view/6a0b15396524d21ee79b868b We also increase the number of the threads in our instrumented CI tests to make these assert failures for buggy patches more likely in future. closes https://github.com/official-stockfish/Stockfish/pull/6830 No functional change
Copyright 2011–2026 Next Chess Move LLC