Racket is distributed under the MIT license and the Apache version 2.0
license, at your option. However, Racket relies on some components
distributed under other licenses. In short:

  * The traditional Racket executable includes code distributed under
  the GNU Lesser General Public License, version 3. This is the
  executable built from code in racket/src/racket.

  * The Racket-on-Chez executable includes code distributed under the
  Apache version 2.0 license, in particular Chez Scheme.

These distinctions apply to the executable `racket` binary, not to
Racket source code and documentation in this repository.

See the file racket/src/LICENSE-LGPL.txt for the full text of the GNU
Lesser General Public License.

See the file racket/src/LICENSE-APACHE.txt for the full text of the
Apache version 2.0 license.

See the file racket/src/LICENSE-MIT.txt for the full text of the
MIT license.

Additionally, the default mode of building Racket will install other
packages, which are distributed under their own license. In the
default mode, all of those packages are distributed under the licenses
listed above.

There may also be other licenses for code within this repository with
which you must comply. Some of them are listed below.

The following are used in all Racket executables:

* mbed TLS. Code from mbed TLS can be found in
  racket/src/rktio/rktio_sha2.c. mbed TLS is licensed under the Apache
  v2.0 License.

The following are used only in the traditional Racket executable:

* libscheme. Code from libscheme can be found in
  racket/src/racket. See the file racket/src/COPYING-libscheme.txt

* GNU Lightning. Code from GNU Lightning can be found in
  racket/src/racket/src. GNU Lightning is distributed under the GNU
  Lesser General Public License version 3.

* GMP. Code from GMP can be found in racket/src/racket/src. The
  version of GMP used is distributed under the GNU Lesser General
  Public License version 2.1.

* The Boehm Collector. Code for this package can be found in
  racket/src/racket/gc. See the file racket/src/racket/gc/README.QUICK
  for license information.

* zlib. Code translated from earlier versions of zlib can be found in
  racket/racket/collects/file/{gzip,gunzip}.rkt. Zlib is distributed
  under a liberal license, see http://zlib.net/

* libffi. Code from libffi can be found in racket/src/foreign/libffi.
  See racket/src/foreign/libffi/LICENSE.

* libunwind. Code from libunwind can be found in
  racket/src/racket/src/unwind.

* random.c. Code from random.c from FreeBSD 2.2 found in
  racket/src/racket/src/random.inc.

* install. Code from install can be found in racket/src/lt/install-sh
  and is distributed under the MIT license.

* MemoryModule. Code from MemoryModule can be found in
  racket/src/start/MemoryModule.c. MemoryModule is distributed under
  the MPL v2.0.

The following are used only in benchmarks, and are not part of the
standard Racket distribution:

* psyntax. Code from psyntax can be found in
  pkgs/racket-benchmarks/tests/racket/benchmarks/common/psyntax.sch
  and is distributed under the Apache v2.0 License.

* SCM. Code from SCM can be found in
  pkgs/racket-benchmarks/tests/racket/benchmarks/shootout/pidigits1.rkt
  SCM is available under the LGPL.


