fairseq-lua
Facebook AI Research Sequence-to-Sequence Toolkit
...Its modular design made it easy to prototype new architectures by modifying encoders, decoders, or attention mechanisms. Although now deprecated in favor of the PyTorch rewrite, fairseq-lua played a key role in advancing large-scale NMT systems, such as early versions of Facebook’s production translation models. It remains an important historical reference for neural sequence learning frameworks.