The qio package includes the following third-party source code. The complete
license texts are retained with the corresponding sources.

carquet
  Files: src/carquet, except src/carquet/compression/snappy.c
  Copyright: 2025 Johan HG Natter
             2024 carquet contributors (Snappy implementation)
  License: MIT
  License file: src/carquet/LICENSE
  Modification: qio applies correctness, build-portability, and error-handling
                fixes to the vendored sources. Each is a separate commit on the
                'qio' branch of https://github.com/pedrobtz/carquet, a fork of
                the upstream project.

Snappy implementation included with carquet
  File: src/carquet/compression/snappy.c
  Copyright: 2005 Google Inc.
             2024 carquet contributors
  License: BSD 3-clause
  License notice: src/carquet/compression/snappy.c

LZ4
  Files: src/lz4
  Copyright: 2011-2023 Yann Collet
  License: BSD 2-clause
  License file: src/lz4/LICENSE

Zstandard
  Files: src/zstd
  Copyright: Meta Platforms, Inc. and affiliates
             Yann Collet
             2016 Tino Reichardt (threading implementation)
  License: BSD 3-clause
  License file: src/zstd/LICENSE
  Modification: Compiler diagnostic pragmas were removed from zstd.h because
                qio compiles the bundled sources as C and does not install the
                header for C++ consumers.

vctrs S3 registration helper
  File: R/zzz.R (qio_s3_register)
  Copyright: 2023 vctrs authors
  License: MIT
  Source: https://github.com/r-lib/vctrs
  Modification: Renamed for qio and kept behaviorally equivalent to the
                upstream s3_register() helper.