PyTorch Lightning

Overview

PyTorch Lightning is a deep learning framework that organizes PyTorch code to eliminate boilerplate while maintaining full flexibility. Automate training workflows, multi-device orchestration, and implement best practices for neural network training and scaling across multiple GPUs/TPUs.

uv pip install lightning   # provides `import lightning as L` and `lightning.pytorch.*`

All code in this skill uses the unified lightning package. The separately published pytorch-lightning package installs the older pytorch_lightning namespace instead; do not mix the two namespaces in one project, because their classes are distinct (e.g. lightning.Trainer.fit rejects a pytorch_lightning.LightningModule with a TypeError).

When to Use This Skill