Skip to content

Dolphin 2.0

Choose a tag to compare

View all tags
@aiagentvn aiagentvn released this 11 Oct 00:11
v2.0.0
8d1b217

First public release of Dolphin, a UCI chess engine written in C# with an NNUE evaluation trained from scratch on its own self-play games.

Download

Dolphin-2.0.0-windows-x64.zip (below, under Assets). Unzip it anywhere and keep these four files together in one folder:

Dolphin2.exe
Dolphin2.dll
Dolphin2.deps.json
Dolphin2.runtimeconfig.json

The engine does not start if only Dolphin2.exe is copied elsewhere. The neural network is embedded in Dolphin2.dll, so no extra network file is needed.

Requirements: Windows, 64-bit (x64) CPU, and the .NET Runtime 5.0 or newer (6, 7, 8, ... also work). CPUs with AVX2 use a faster NNUE code path.

Use it in a chess GUI

Arena: Engines → Install New Engine... → select Dolphin2.exe → choose UCI.
Cute Chess / BanksiaGUI / others: set the engine command to the full path of Dolphin2.exe, protocol UCI.

If the engine does not move and loses on time, run Dolphin2.exe in a command prompt and type uci. You should see uciok. An error about hostpolicy.dll / runtimeconfig.json means one of the four files is missing. An error that the framework Microsoft.NETCore.App was not found means the .NET Runtime is not installed. The included README.txt has more details.

What's inside

  • Bitboards with magic bitboard attacks, fully legal move generation (perft-verified)
  • Principal Variation Search with iterative deepening, aspiration windows, null-move pruning, LMR, singular extensions, ProbCut, SEE and more
  • Multi-threaded search (Lazy SMP), time management for all common time controls, pondering
  • NNUE evaluation: 768 inputs → 384 hidden neurons per perspective (SCReLU) → 8 output buckets, incrementally updated, AVX2 fast path
  • The bundled network was trained only on positions from Dolphin's own self-play games (about 28 million positions)
  • Built-in datagen and train commands to generate data and train your own network
  • UCI options: Hash, Threads, Move Overhead, Ponder, Clear Hash, UseNNUE, EvalFile

See the README for full documentation.

Verify

  • Dolphin2.exe perft 5 must print Nodes searched: 4865609
  • SHA-256 of Dolphin-2.0.0-windows-x64.zip:
    BECCB1DF98D6A68CFD499BBC0E9EAAAECF598552D29EABE0449C0E67EE066008

Build from source

git clone https://github.com/aiagentvn/dolphin.git
cd dolphin
dotnet build -c Release

The binaries in this release were built from the source at this tag.

Assets 3
Loading