V Ultrabullet IJCCRL Rating list Derived stockfish 2026 — Specification
Launcher-enforced parameters (ultrabullet 10s+0.1s, scientific & reproducible)
TC 10+0.1
Threads 1
Hash 32 MB
UHO 2024
Syzygy 6-man
Concurrency 2
OwnBook false
Scope: V Ultrabullet IJCCRL season 2026 — Stockfish-derived engines only
Goal: Stable, reproducible rating list for Stockfish derivatives at ultrabullet time control
V Ultrabullet IJCCRL Rating list Derived stockfish 2026 — Participants
Stockfish-derived chess engines competing under identical ultrabullet settings (10s+0.1s)
| # | Engine | Category | Notes |
|---|---|---|---|
| 1 | brainlearnjrc | Stockfish derivative | IJCCRL-tuned BrainLearn variant, ultrabullet configuration |
| 2 | Killfish PB 260126_sse41 | Stockfish derivative | Optimised UCI engine tested under 10s+0.1s |
| 3 | Dark SisTer 11_sse41 | Stockfish derivative | Aggressive profile, ultrabullet stress-tested |
| 4 | Artemis 26.1TR_PrO_sse41 | Stockfish derivative | TR/Pro tuned build for fast time controls |
| 5 | SpecTral 12_sse41 | Stockfish derivative | Spectral-style engine, identical IJCCRL launcher settings |
| 6 | Wordfish-4.0.1-260126-sse41po | Stockfish derivative | Wordfish line, SSE4.1 POPCNT build |
| 7 | Deepalienist-2.90-120126-sse41popcnt | Stockfish derivative | Deepalienist branch, tuned for ultrabullet experiments |
| 8 | Brainlearn31-x86-64-sse41-popcnt | Stockfish derivative | Reference BrainLearn 31 build under IJCCRL conditions |
| 9 | stockfish 17.1 | Reference baseline | Upstream Stockfish, used as anchor in the derived list |
| 10 | Revolution-4.60-230126-sse41popcnt | Stockfish derivative | IJCCRL Revolution branch, SSE4.1 POPCNT build |
| 11 | HypnoS 1.01 popcnt | Stockfish derivative | HypnoS family, POPCNT-optimised build |
| 12 | ShashChess40-x86-64-sse41-pop | Stockfish derivative | ShashChess flavour, same ultrabullet settings |
| 13 | DON-SSE41 | Stockfish derivative | SSE4.1 build, tested under UHO 2024 suite |
| 14 | RapTora 6.0_ssse3 | Stockfish derivative | SSSE3 build; same launcher, same hardware constraints |
Fairness: same UHO 2024 suite, same options, same limits, no private books
Composition: Stockfish-derived engines only, plus reference upstream build
V Ultrabullet IJCCRL Rating list Derived stockfish 2026 — Tournament Settings
Technical rules enforced by the launcher (transparent and reproducible)
| Parameter | Value | Purpose |
|---|---|---|
| Time control | 10s + 0.1s | Ultrabullet profile: hard time pressure and stability testing for Stockfish derivatives |
| Threads | 1 | Strict comparability across all engines (no SMP scaling advantages) |
| Hash | 32 MB | Uniform transposition table allocation tuned for ultrabullet time limits |
| Opening suite | UHO 2024 (PGN) | Controlled diversity and reduced bias; mirrored colours for every pairing |
| OwnBook | false | No private opening books; highlights engine search and evaluation |
| Syzygy | 6-man | Endgame correctness, clean conversion and consistent adjudication |
| Concurrency | 2 | Parallel execution for higher volume on the host while avoiding overload |
| Games per pairing | 2 | Colour symmetry for every engine pair; lower variance in scores |
| Max moves | 200 | Prevents runaway games, stabilises throughput and adjudication horizon |
| Season | 2026 | Large dataset for statistical confidence in Ordo & BayesElo ratings |
Method: same rules for all engines, documented settings, large sample size
Outcome: a differentiated ultrabullet rating list for Stockfish-derived engines
V Ultrabullet IJCCRL Rating list Derived stockfish 2026 — Final standings
Combined Ordo & BayesElo snapshot (784 games each)
| # | Engine | Ordo rating | Ordo points | Ordo games | Ordo score % | BayesElo | + | − | BayesElo games | BayesElo score % | Opp. diff | Draw % |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| 1 | brainlearnjrc | 3745.1 | 446.0 | 784 | 57 | 43 | 19 | 19 | 784 | 57% | -3 | 38% |
| 2 | Killfish PB 260126_sse41 | 3722.0 | 418.5 | 784 | 53 | 21 | 19 | 19 | 784 | 53% | -2 | 37% |
| 3 | Dark SisTer 11_sse41 | 3715.5 | 410.5 | 784 | 52 | 15 | 19 | 19 | 784 | 52% | -1 | 35% |
| 4 | Artemis 26.1TR_PrO_sse41 | 3712.1 | 406.5 | 784 | 52 | 11 | 19 | 19 | 784 | 52% | -1 | 35% |
| 5 | SpecTral 12_sse41 | 3706.7 | 400.0 | 784 | 51 | 7 | 19 | 19 | 784 | 51% | 0 | 33% |
| 6 | Wordfish-4.0.1-260126-sse41po | 3704.6 | 397.5 | 784 | 51 | 4 | 19 | 19 | 784 | 51% | 0 | 36% |
| 7 | Deepalienist-2.90-120126-sse41popcnt | 3701.5 | 394.0 | 784 | 50 | 2 | 19 | 19 | 784 | 50% | 0 | 34% |
| 8 | Brainlearn31-x86-64-sse41-popcnt | 3700.2 | 392.5 | 784 | 50 | 0 | 19 | 19 | 784 | 50% | 0 | 35% |
| 9 | stockfish 17.1 | 3696.2 | 387.5 | 784 | 49 | -3 | 19 | 19 | 784 | 49% | 0 | 38% |
| 10 | Revolution-4.60-230126-sse41popcnt | 3692.1 | 382.5 | 784 | 49 | -8 | 19 | 19 | 784 | 49% | 1 | 37% |
| 11 | HypnoS 1.01 popcnt | 3690.9 | 381.0 | 784 | 49 | -9 | 19 | 19 | 784 | 49% | 1 | 39% |
| 12 | ShashChess40-x86-64-sse41-pop | 3676.4 | 363.5 | 784 | 46 | -22 | 19 | 19 | 784 | 46% | 2 | 35% |
| 13 | DON-SSE41 | 3673.8 | 360.5 | 784 | 46 | -25 | 19 | 19 | 784 | 46% | 2 | 38% |
| 14 | RapTora 6.0_ssse3 | 3663.0 | 347.5 | 784 | 44 | -36 | 19 | 19 | 784 | 44% | 3 | 35% |
White advantage: 0.00
Draw rate (equal opponents): 50.00 %
2026 January
Fabruary
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