; and (2) involves— (A) the incremental development and fielding of capabilities, commonly called “spirals”, “spins”, or “sprints”, which can be measured in a few weeks or months; and (B) continuous participation and collaboration by users, testers, and requirements authorities. 886. Use of open source software (a) Open source software (1) In general Chapter 137 of title 10, United States Code, is amended by inserting after section 2320 the following new section: 2320a. Use of open source software (a) Software development All unclassified custom-developed computer software and related technical data that is not a defense article regulated pursuant to section 38 of the Arms Export Control Act ( 22 U.S.C. 2778 ) and that is developed under a contract or other transaction awarded by the Department of Defense on or after the date that is 180 days after the date of the enactment of this section shall be managed as open source software unless specifically waived by the service acquisition executive. (b) Release of software in public repository The Secretary of Defense shall require the contractor to release source code and related technical data described under subsection (a) in a public repository approved by the Department of Defense, subject to a license through which the copyright holder provides the rights to use, study, reuse, modify, enhance, and distribute the software to anyone and for any purpose. (c) Applicability to existing software The Secretary of Defense shall, where appropriate— (1) apply open source licenses to existing custom-developed computer software