Highlights
- First open-source release — GaiaChess is now open source under GPLv3, engine and NNUE trainer included. Source: https://github.com/jromang/gaiachess
- Minor search improvements over 4.2.1 (two SPRT-validated heuristic refinements).
Download
Pick the binary matching your CPU. Windows binaries end in .exe, Linux and macOS have no extension.
Which binary should I use?
| CPU | Recommended binary |
|---|---|
| AMD Ryzen 9000 (Zen 5) | znver5 or avx512vnni |
| AMD Ryzen 7000 (Zen 4) | znver4 or avx512 |
| AMD Ryzen 5000 (Zen 3) | znver3 or bmi2 |
| AMD Ryzen 1000–3000 (Zen 1/2) | avx2 |
| Intel 12th gen+ (Alder Lake+) | avx512vnni |
| Intel 10th–11th gen | avx512 or bmi2 |
| Intel Haswell–Coffee Lake | bmi2 |
| Apple M1/M2/M3/M4 | apple-silicon |
| Linux ARM64 (RPi 4+, Graviton) | neon |
| Older CPUs (pre-2013) | sse4-popcnt, ssse3, or x86-64 |
When in doubt, use bmi2 (x86) or neon (ARM).
Binary details
| Suffix | SIMD | Eval | Target CPUs |
|---|---|---|---|
x86-64 |
— | PeSTO | Any x86-64 CPU (2003+) |
ssse3 |
SSSE3 | PeSTO | Core 2+ (2006+) |
sse4-popcnt |
SSE4 + POPCNT | PeSTO | Nehalem+ (2008+) |
avx2 |
AVX2 | NNUE | Haswell+, Zen 1/2 (no fast PEXT) |
bmi2 |
AVX2 + PEXT | NNUE | Haswell+, Zen 3+ |
avx512 |
AVX-512 | NNUE | Skylake-X, Zen 4 |
avx512vnni |
AVX-512 + VNNI | NNUE | Ice Lake+, Zen 5 |
znver3 |
AVX2 + PEXT | NNUE | AMD Ryzen 5000 (tuned) |
znver4 |
AVX-512 | NNUE | AMD Ryzen 7000 (tuned) |
znver5 |
AVX-512 + VNNI | NNUE | AMD Ryzen 9000 (tuned) |
neon |
NEON | NNUE | ARM64 Linux |
apple-silicon |
NEON | NNUE | macOS Apple Silicon |
All x86-64 binaries are compiled with PGO (Profile-Guided Optimization) for maximum performance.
The AVX-512 variants are profiled under Intel SDE, since no CI runner is guaranteed to support AVX-512.
NNUE binaries embed the neural network — no external file needed.
PeSTO binaries (x86-64, ssse3, sse4-popcnt) use a classical evaluation for older hardware.