path: root/COPYING

License information for this artifact
=====================================

This artifact consists of a few parts. We choose to license most of
our code under the 3-clause BSD license (SPDX: BSD-3-Clause), with an
exception of the Nix test suite that we have adopted, which remains
licensed under LGPL 2.1 (SPDX: LGPL-2.1-or-later).

Specifically:
- The following files in lib/nix/ are derived from nixformat [1] by
  Denis Korzunov:
    lexer.ml, nix.ml, parser.mly, printer.ml and types.ml
  nixformat is licensed under ISC (SPDX: ISC). For consistency, we
  choose to relicense these files under the 3-clause BSD license (as
  it subsumes the ISC license). We also include a copy of the ISC
  license as required.
- The files in test/testdata/ come from Nix [2] and remain licensed
  under version 2.1 of the LGPL license. We also include a copy of
  this license below. The only exception here is the file
    test/testdata/importdef.sexp
  which was created by us (and is therefore licensed under the 3-clause BSD
  license).
- Any files not described by the preceding items is licensed under the
  3-clause BSD license.

[1]: https://github.com/d2km/nixformat
[2]: https://github.com/NixOs/nix


The 3-clause BSD license (BSD-3-Clause)
---------------------------------------

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The ISC license (ISC)
---------------------

Permission to use, copy, modify, and /or distribute this software for
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THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL
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