Blackfriday is distributed under the Simplified BSD License:

> Copyright © 2011 Russ Ross
> All rights reserved.
>
> Redistribution and use in source and binary forms, with or without
> modification, are permitted provided that the following conditions
> are met:
>
> 1.  Redistributions of source code must retain the above copyright
>     notice, this list of conditions and the following disclaimer.
>

unrestricted_licenses:
  - Apache-2.0
  - CC-BY-3.0
  - ISC
  - AFL-2.1
  - AFL-3.0
  - Artistic-1.0
  - Artistic-2.0
  - Apache-1.1
  - BSD-1-Clause
  - BSD-2-Clause
  - BSD-3-Clause
  - 0BSD
  - FTL
  - LPL-1.02
  - MS-PL
  - MIT
  - NCSA
  - OpenSSL
  - PHP-3.0
  - TCP-wrappers
  - W3C
  - Xnet
  - Zlib

reciprocal_licenses:
  - CC0-1.0
  - APSL-2.0
  - CDDL-1.0
  - CDDL-1.1

BSD 3-Clause License

Copyright (c) 2009, The Go Authors. Extensions copyright (c) 2011, Miek Gieben. 
All rights reserved.

Redistribution and use in source and binary forms, with or without
modification, are permitted provided that the following conditions are met:

1. Redistributions of source code must retain the above copyright notice, this
   list of conditions and the following disclaimer.