Backend

Neural network topology

The Leela Chess Zero’s neural network is largely based on the DeepMind’s AlphaGo Zero1 and AlphaZero2 architecture. There are however some changes. Network topology The core of the network is a residual tower with Squeeze and Excitation3 (SE) layers.

C++ interface

Implement your own Lc0 backend in four simple steps: Implement Network and NetworkComputation interface. Write a factory function to create your backend. Register your factory function using REGISTER_NETWORK macro. Link your implementation with Lc0.

Weights file format

The NN weights file is in Google Protocol Buffers1 format. The schema definition is located in the lczero-common repository. NN format description The network format description is contained in weights.format().network_format() submessage.