The rcxl package as a whole is released under MIT + file LICENSE.

Everything under R/, tests/, tools/, src/read_xlsx.c, src/init.c and
src/xthread.h is Copyright (c) 2026 Vincent Shields, under that license.

The package additionally bundles two third-party C libraries, both under the
MIT license, reproduced in full below.


-------------------------------------------------------------------------
src/miniz.c, src/miniz.h -- miniz 11.0.2 (https://github.com/richgel999/miniz)

The ZIP writing API is compiled out: the build defines
MINIZ_NO_ARCHIVE_WRITING_APIS and MINIZ_NO_ZLIB_COMPATIBLE_NAMES (see
src/Makevars). The source files are otherwise unmodified upstream copies.

miniz also carries these individually credited contributions, all reproduced
as shipped upstream:

  * The ZIP reader section (miniz.c, "miniz_zip") is additionally
    Copyright 2016 Martin Raiber, under the same MIT license below.
  * tdefl_write_image_to_png_file_in_memory_ex() is a modification of a PNG
    writer by Alex Evans (2011), which he released into the public domain
    (https://gist.github.com/908299).
  * tdefl_calculate_minimum_redundancy() was originally written by Alistair
    Moffat and Jyrki Katajainen (November 1996).
-------------------------------------------------------------------------

Copyright 2013-2014 RAD Game Tools and Valve Software
Copyright 2010-2014 Rich Geldreich and Tenacious Software LLC
Copyright 2016 Martin Raiber
All Rights Reserved.

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in
all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
THE SOFTWARE.


-------------------------------------------------------------------------
src/libdeflate/** -- libdeflate 1.24
(https://github.com/ebiggers/libdeflate)

This is a partial copy: only the decompressor is vendored, namely
lib/deflate_decompress.c, lib/utils.c, lib/x86/cpu_features.c,
lib/arm/cpu_features.c and their headers. The compressor is not included.
-------------------------------------------------------------------------

Copyright 2016 Eric Biggers
Copyright 2024 Google LLC

Permission is hereby granted, free of charge, to any person
obtaining a copy of this software and associated documentation files
(the "Software"), to deal in the Software without restriction,
including without limitation the rights to use, copy, modify, merge,
publish, distribute, sublicense, and/or sell copies of the Software,
and to permit persons to whom the Software is furnished to do so,
subject to the following conditions:

The above copyright notice and this permission notice shall be
included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.