USASI
SoftwareFramework

PyTorch Lightning

Project record

Maintained by Lightning AI197

PyTorch Lightning is an open-source Python framework that structures PyTorch training code and handles engineering tasks such as multi-GPU and multi-node distributed training and mixed precision. The same repository contains Lightning Fabric, a lighter layer for scaling custom PyTorch training loops, and both ship in the lightning package. It was open-sourced in 2019 and is maintained by Lightning AI.19

Last reviewedEntry updated Documented release 2019

Availability and license

Overall availability

Public

Documented as available to the general public. Access conditions and license terms may still apply.12

Availability is separate from permission: read the license before using or redistributing.

Public materials checklist

Items for a framework under USASI rubric v0.1. Unknown means unassessed or insufficient evidence.
Public materials checklist for PyTorch Lightning
ItemStatusNotes and evidence
Source codeIs the source code publicly readable?Public1
DocumentationIs user documentation published?PublicDocumentation is hosted on lightning.ai; the stable docs were for version 2.6.6 at review.5
InstallationAre installation instructions or packages publicly available?PublicInstallable with pip (python -m pip install lightning), from conda-forge, or from source archives on GitHub.5
Supported platformsAre supported operating systems or hardware documented?PublicThe README's continuous-integration table covers Linux, macOS, and Windows, and it documents running on CPUs, CUDA or MPS GPUs, and TPUs.1
Release statusAre versioned releases published?PublicVersioned releases are published on GitHub and PyPI; the latest at review was 2.6.6, released on September 10, 2026.34

What it is useful for

Training and fine-tuning PyTorch models on CPUs, GPUs (CUDA or Apple MPS), or TPUs, from a single device to multiple nodes, without rewriting the model code.1

Run and use notes

Documented facts only. No hardware or performance claims are made without a cited source and stated assumptions.
  • Security: versions 2.6.2 and 2.6.3 uploaded to PyPI on April 30, 2026 were published by an attacker using stolen PyPI credentials and ran a credential-stealing payload on import (CVE-2026-44484). Lightning AI says the GitHub source was not affected, the two versions were quarantined and retired, and anyone who imported them should rotate exposed credentials; later releases start at 2.6.4.783

Organization context

U.S. eligibility

Project eligibility rests on documented governing or maintaining entities, not on contributors.

Eligible · basis: U.S.-governed project

The project is hosted in Lightning AI's GitHub organization, and Lightning AI describes itself as the creator of PyTorch Lightning and handled the project's April 2026 security advisory and PyPI publishing. Lightning AI's documented entities are U.S.-based: an SEC Form D filed in January 2026 by Lightning AI, Inc. (Delaware) gives a San Francisco principal place of business, and the website privacy policy gives a New York address for Grid.ai, Inc. doing business as Lightning AI. The project's governance page gives final decisions to a single project lead and release decisions to its maintainers; this assessment rests on the maintaining company, not on individuals.19711106

Assessed Sep 29, 2026

Sources

  1. 1.
    Lightning-AI/pytorch-lightning (external site: github.com)

    Lightning AI · Repository · accessed Sep 29, 2026

  2. 2.
    Lightning-AI/pytorch-lightning LICENSE (external site: github.com)

    Lightning AI · License · accessed Sep 29, 2026

  3. 3.
    Lightning-AI/pytorch-lightning releases (external site: github.com)

    Lightning AI · Release notes · accessed Sep 29, 2026

  4. 4.
    lightning package metadata (PyPI JSON API) (external site: pypi.org)

    Python Package Index · Other · accessed Sep 29, 2026

  5. 5.
    Install - PyTorch Lightning Docs (external site: lightning.ai)

    Lightning AI · Documentation · accessed Sep 29, 2026

  6. 6.
    Lightning Governance - PyTorch Lightning Docs (external site: lightning.ai)

    Lightning AI · Documentation · accessed Sep 29, 2026

  7. 7.
    Compromise of PyTorch Lightning PyPi Package Versions (GHSA-w37p-236h-pfx3) (external site: github.com)

    Lightning AI · Announcement · published Apr 30, 2026 · accessed Sep 29, 2026

  8. 8.
  9. 9.
    About Lightning AI (external site: lightning.ai)

    Lightning AI · Official page · accessed Sep 29, 2026

  10. 10.
    Lightning AI Privacy Policy (external site: lightning.ai)

    Lightning AI · Official page · published Aug 20, 2023 · accessed Sep 29, 2026

  11. 11.
    Lightning AI, Inc. Form D (Notice of Exempt Offering of Securities) (external site: sec.gov)

    U.S. Securities and Exchange Commission (filed by Lightning AI, Inc.) · Filing · published Jan 8, 2026 · accessed Sep 29, 2026

This listing is not an endorsement, a safety assessment, or a federal approval.

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