Heavily favored by the Perl community, the Artistic license requires that modified versions of the software do not prevent users from running the standard version.
The Artistic License 2.0Copyright (c) 2000-2006, The Perl Foundation.Everyone is permitted to copy and distribute verbatim copiesof this license document, but changing it is not allowed.PreambleThis license establishes the terms under which a given free softwarePackage may be copied, modified, distributed, and/or redistributed.The intent is that the Copyright Holder maintains some artisticcontrol over the development of that Package while still keeping thePackage available as open source and free software.You are always permitted to make arrangements wholly outside of thislicense directly with the Copyright Holder of a given Package. If theterms of this license do not permit the full use that you propose tomake of the Package, you should contact the Copyright Holder and seeka different licensing arrangement.Definitions"Copyright Holder" means the individual(s) or organization(s)named in the copyright notice for the entire Package."Contributor" means any party that has contributed code or othermaterial to the Package, in accordance with the Copyright Holder'sprocedures."You" and "your" means any person who would like to copy,distribute, or modify the Package."Package" means the collection of files distributed by theCopyright Holder, and derivatives of that collection and/or ofthose files. A given Package may consist of either the StandardVersion, or a Modified Version."Distribute" means providing a copy of the Package or making itaccessible to anyone else, or in the case of a company ororganization, to others outside of your company or organization."Distributor Fee" means any fee that you charge for Distributingthis Package or providing support for this Package to anotherparty. It does not mean licensing fees."Standard Version" refers to the Package if it has not beenmodified, or has been modified only in ways explicitly requestedby the Copyright Holder."Modified Version" means the Package, if it has been changed, andsuch changes were not explicitly requested by the CopyrightHolder."Original License" means this Artistic License as Distributed withthe Standard Version of the Package, in its current version or asit may be modified by The Perl Foundation in the future."Source" form means the source code, documentation source, andconfiguration files for the Package."Compiled" form means the compiled bytecode, object code, binary,or any other form resulting from mechanical transformation ortranslation of the Source form.Permission for Use and Modification Without Distribution(1) You are permitted to use the Standard Version and create and useModified Versions for any purpose without restriction, provided thatyou do not Distribute the Modified Version.Permissions for Redistribution of the Standard Version(2) You may Distribute verbatim copies of the Source form of theStandard Version of this Package in any medium without restriction,either gratis or for a Distributor Fee, provided that you duplicateall of the original copyright notices and associated disclaimers. Atyour discretion, such verbatim copies may or may not include aCompiled form of the Package.(3) You may apply any bug fixes, portability changes, and othermodifications made available from the Copyright Holder. The resultingPackage will still be considered the Standard Version, and as suchwill be subject to the Original License.Distribution of Modified Versions of the Package as Source(4) You may Distribute your Modified Version as Source (either gratisor for a Distributor Fee, and with or without a Compiled form of theModified Version) provided that you clearly document how it differsfrom the Standard Version, including, but not limited to, documentingany non-standard features, executables, or modules, and provided thatyou do at least ONE of the following:(a) make the Modified Version available to the Copyright Holderof the Standard Version, under the Original License, so that theCopyright Holder may include your modifications in the StandardVersion.(b) ensure that installation of your Modified Version does notprevent the user installing or running the Standard Version. Inaddition, the Modified Version must bear a name that is differentfrom the name of the Standard Version.(c) allow anyone who receives a copy of the Modified Version tomake the Source form of the Modified Version available to othersunder(i) the Original License or(ii) a license that permits the licensee to freely copy,modify and redistribute the Modified Version using the samelicensing terms that apply to the copy that the licenseereceived, and requires that the Source form of the ModifiedVersion, and of any works derived from it, be made freelyavailable in that license fees are prohibited but DistributorFees are allowed.Distribution of Compiled Forms of the Standard Versionor Modified Versions without the Source(5) You may Distribute Compiled forms of the Standard Version withoutthe Source, provided that you include complete instructions on how toget the Source of the Standard Version. Such instructions must bevalid at the time of your distribution. If these instructions, at anytime while you are carrying out such distribution, become invalid, youmust provide new instructions on demand or cease further distribution.If you provide valid instructions or cease distribution within thirtydays after you become aware that the instructions are invalid, thenyou do not forfeit any of your rights under this license.(6) You may Distribute a Modified Version in Compiled form withoutthe Source, provided that you comply with Section 4 with respect tothe Source of the Modified Version.Aggregating or Linking the Package(7) You may aggregate the Package (either the Standard Version orModified Version) with other packages and Distribute the resultingaggregation provided that you do not charge a licensing fee for thePackage. Distributor Fees are permitted, and licensing fees for othercomponents in the aggregation are permitted. The terms of this licenseapply to the use and Distribution of the Standard or Modified Versionsas included in the aggregation.(8) You are permitted to link Modified and Standard Versions withother works, to embed the Package in a larger work of your own, or tobuild stand-alone binary or bytecode versions of applications thatinclude the Package, and Distribute the result without restriction,provided the result does not expose a direct interface to the Package.Items That are Not Considered Part of a Modified Version(9) Works (including, but not limited to, modules and scripts) thatmerely extend or make use of the Package, do not, by themselves, causethe Package to be a Modified Version. In addition, such works are notconsidered parts of the Package itself, and are not subject to theterms of this license.General Provisions(10) Any use, modification, and distribution of the Standard orModified Versions is governed by this Artistic License. By using,modifying or distributing the Package, you accept this license. Do notuse, modify, or distribute the Package, if you do not accept thislicense.(11) If your Modified Version has been derived from a ModifiedVersion made by someone other than you, you are nevertheless requiredto ensure that your Modified Version complies with the requirements ofthis license.(12) This license does not grant you the right to use any trademark,service mark, tradename, or logo of the Copyright Holder.(13) This license includes the non-exclusive, worldwide,free-of-charge patent license to make, have made, use, offer to sell,sell, import and otherwise transfer the Package with respect to anypatent claims licensable by the Copyright Holder that are necessarilyinfringed by the Package. If you institute patent litigation(including a cross-claim or counterclaim) against any party allegingthat the Package constitutes direct or contributory patentinfringement, then this Artistic License to you shall terminate on thedate that such litigation is filed.(14) Disclaimer of Warranty:THE PACKAGE IS PROVIDED BY THE COPYRIGHT HOLDER AND CONTRIBUTORS "ASIS' AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES. THE IMPLIEDWARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, ORNON-INFRINGEMENT ARE DISCLAIMED TO THE EXTENT PERMITTED BY YOUR LOCALLAW. UNLESS REQUIRED BY LAW, NO COPYRIGHT HOLDER OR CONTRIBUTOR WILLBE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, OR CONSEQUENTIALDAMAGES ARISING IN ANY WAY OUT OF THE USE OF THE PACKAGE, EVEN IFADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
：Code submit frequency
：React/respond to issue & PR etc.
：Well-balanced team members and collaboration
：Recent popularity of project
：Star counts, download counts etc.