diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 29abbbf8f262110dbd0b485b70eac0b240a22a81..f13650e68447506a824ab31ad0a91088d52d8be4 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 image: fedora:latest
 stages:
   - build
diff --git a/LICENSE b/LICENSE
deleted file mode 100644
index 167a550fa964627e8d7b4cf45ad4e77c2eb2a166..0000000000000000000000000000000000000000
--- a/LICENSE
+++ /dev/null
@@ -1,201 +0,0 @@
-                                 Apache License
-                           Version 2.0, January 2004
-                        http://www.apache.org/licenses/
-
-   TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION
-
-   1. Definitions.
-
-      "License" shall mean the terms and conditions for use, reproduction,
-      and distribution as defined by Sections 1 through 9 of this document.
-
-      "Licensor" shall mean the copyright owner or entity authorized by
-      the copyright owner that is granting the License.
-
-      "Legal Entity" shall mean the union of the acting entity and all
-      other entities that control, are controlled by, or are under common
-      control with that entity. For the purposes of this definition,
-      "control" means (i) the power, direct or indirect, to cause the
-      direction or management of such entity, whether by contract or
-      otherwise, or (ii) ownership of fifty percent (50%) or more of the
-      outstanding shares, or (iii) beneficial ownership of such entity.
-
-      "You" (or "Your") shall mean an individual or Legal Entity
-      exercising permissions granted by this License.
-
-      "Source" form shall mean the preferred form for making modifications,
-      including but not limited to software source code, documentation
-      source, and configuration files.
-
-      "Object" form shall mean any form resulting from mechanical
-      transformation or translation of a Source form, including but
-      not limited to compiled object code, generated documentation,
-      and conversions to other media types.
-
-      "Work" shall mean the work of authorship, whether in Source or
-      Object form, made available under the License, as indicated by a
-      copyright notice that is included in or attached to the work
-      (an example is provided in the Appendix below).
-
-      "Derivative Works" shall mean any work, whether in Source or Object
-      form, that is based on (or derived from) the Work and for which the
-      editorial revisions, annotations, elaborations, or other modifications
-      represent, as a whole, an original work of authorship. For the purposes
-      of this License, Derivative Works shall not include works that remain
-      separable from, or merely link (or bind by name) to the interfaces of,
-      the Work and Derivative Works thereof.
-
-      "Contribution" shall mean any work of authorship, including
-      the original version of the Work and any modifications or additions
-      to that Work or Derivative Works thereof, that is intentionally
-      submitted to Licensor for inclusion in the Work by the copyright owner
-      or by an individual or Legal Entity authorized to submit on behalf of
-      the copyright owner. For the purposes of this definition, "submitted"
-      means any form of electronic, verbal, or written communication sent
-      to the Licensor or its representatives, including but not limited to
-      communication on electronic mailing lists, source code control systems,
-      and issue tracking systems that are managed by, or on behalf of, the
-      Licensor for the purpose of discussing and improving the Work, but
-      excluding communication that is conspicuously marked or otherwise
-      designated in writing by the copyright owner as "Not a Contribution."
-
-      "Contributor" shall mean Licensor and any individual or Legal Entity
-      on behalf of whom a Contribution has been received by Licensor and
-      subsequently incorporated within the Work.
-
-   2. Grant of Copyright License. Subject to the terms and conditions of
-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      copyright license to reproduce, prepare Derivative Works of,
-      publicly display, publicly perform, sublicense, and distribute the
-      Work and such Derivative Works in Source or Object form.
-
-   3. Grant of Patent License. Subject to the terms and conditions of
-      this License, each Contributor hereby grants to You a perpetual,
-      worldwide, non-exclusive, no-charge, royalty-free, irrevocable
-      (except as stated in this section) patent license to make, have made,
-      use, offer to sell, sell, import, and otherwise transfer the Work,
-      where such license applies only to those patent claims licensable
-      by such Contributor that are necessarily infringed by their
-      Contribution(s) alone or by combination of their Contribution(s)
-      with the Work to which such Contribution(s) was submitted. If You
-      institute patent litigation against any entity (including a
-      cross-claim or counterclaim in a lawsuit) alleging that the Work
-      or a Contribution incorporated within the Work constitutes direct
-      or contributory patent infringement, then any patent licenses
-      granted to You under this License for that Work shall terminate
-      as of the date such litigation is filed.
-
-   4. Redistribution. You may reproduce and distribute copies of the
-      Work or Derivative Works thereof in any medium, with or without
-      modifications, and in Source or Object form, provided that You
-      meet the following conditions:
-
-      (a) You must give any other recipients of the Work or
-          Derivative Works a copy of this License; and
-
-      (b) You must cause any modified files to carry prominent notices
-          stating that You changed the files; and
-
-      (c) You must retain, in the Source form of any Derivative Works
-          that You distribute, all copyright, patent, trademark, and
-          attribution notices from the Source form of the Work,
-          excluding those notices that do not pertain to any part of
-          the Derivative Works; and
-
-      (d) If the Work includes a "NOTICE" text file as part of its
-          distribution, then any Derivative Works that You distribute must
-          include a readable copy of the attribution notices contained
-          within such NOTICE file, excluding those notices that do not
-          pertain to any part of the Derivative Works, in at least one
-          of the following places: within a NOTICE text file distributed
-          as part of the Derivative Works; within the Source form or
-          documentation, if provided along with the Derivative Works; or,
-          within a display generated by the Derivative Works, if and
-          wherever such third-party notices normally appear. The contents
-          of the NOTICE file are for informational purposes only and
-          do not modify the License. You may add Your own attribution
-          notices within Derivative Works that You distribute, alongside
-          or as an addendum to the NOTICE text from the Work, provided
-          that such additional attribution notices cannot be construed
-          as modifying the License.
-
-      You may add Your own copyright statement to Your modifications and
-      may provide additional or different license terms and conditions
-      for use, reproduction, or distribution of Your modifications, or
-      for any such Derivative Works as a whole, provided Your use,
-      reproduction, and distribution of the Work otherwise complies with
-      the conditions stated in this License.
-
-   5. Submission of Contributions. Unless You explicitly state otherwise,
-      any Contribution intentionally submitted for inclusion in the Work
-      by You to the Licensor shall be under the terms and conditions of
-      this License, without any additional terms or conditions.
-      Notwithstanding the above, nothing herein shall supersede or modify
-      the terms of any separate license agreement you may have executed
-      with Licensor regarding such Contributions.
-
-   6. Trademarks. This License does not grant permission to use the trade
-      names, trademarks, service marks, or product names of the Licensor,
-      except as required for reasonable and customary use in describing the
-      origin of the Work and reproducing the content of the NOTICE file.
-
-   7. Disclaimer of Warranty. Unless required by applicable law or
-      agreed to in writing, Licensor provides the Work (and each
-      Contributor provides its Contributions) on an "AS IS" BASIS,
-      WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or
-      implied, including, without limitation, any warranties or conditions
-      of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR A
-      PARTICULAR PURPOSE. You are solely responsible for determining the
-      appropriateness of using or redistributing the Work and assume any
-      risks associated with Your exercise of permissions under this License.
-
-   8. Limitation of Liability. In no event and under no legal theory,
-      whether in tort (including negligence), contract, or otherwise,
-      unless required by applicable law (such as deliberate and grossly
-      negligent acts) or agreed to in writing, shall any Contributor be
-      liable to You for damages, including any direct, indirect, special,
-      incidental, or consequential damages of any character arising as a
-      result of this License or out of the use or inability to use the
-      Work (including but not limited to damages for loss of goodwill,
-      work stoppage, computer failure or malfunction, or any and all
-      other commercial damages or losses), even if such Contributor
-      has been advised of the possibility of such damages.
-
-   9. Accepting Warranty or Additional Liability. While redistributing
-      the Work or Derivative Works thereof, You may choose to offer,
-      and charge a fee for, acceptance of support, warranty, indemnity,
-      or other liability obligations and/or rights consistent with this
-      License. However, in accepting such obligations, You may act only
-      on Your own behalf and on Your sole responsibility, not on behalf
-      of any other Contributor, and only if You agree to indemnify,
-      defend, and hold each Contributor harmless for any liability
-      incurred by, or claims asserted against, such Contributor by reason
-      of your accepting any such warranty or additional liability.
-
-   END OF TERMS AND CONDITIONS
-
-   APPENDIX: How to apply the Apache License to your work.
-
-      To apply the Apache License to your work, attach the following
-      boilerplate notice, with the fields enclosed by brackets "{}"
-      replaced with your own identifying information. (Don't include
-      the brackets!)  The text should be enclosed in the appropriate
-      comment syntax for the file format. We also recommend that a
-      file or class name and description of purpose be included on the
-      same "printed page" as the copyright notice for easier
-      identification within third-party archives.
-
-   Copyright 2018 Bruce Cowan
-
-   Licensed under the Apache License, Version 2.0 (the "License");
-   you may not use this file except in compliance with the License.
-   You may obtain a copy of the License at
-
-       http://www.apache.org/licenses/LICENSE-2.0
-
-   Unless required by applicable law or agreed to in writing, software
-   distributed under the License is distributed on an "AS IS" BASIS,
-   WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-   See the License for the specific language governing permissions and
-   limitations under the License.
diff --git a/LICENSES/Apache-2.0.txt b/LICENSES/Apache-2.0.txt
new file mode 100644
index 0000000000000000000000000000000000000000..4ed90b952240cb872426e64da9e41252cc61ae3e
--- /dev/null
+++ b/LICENSES/Apache-2.0.txt
@@ -0,0 +1,208 @@
+Apache License
+
+Version 2.0, January 2004
+
+http://www.apache.org/licenses/ TERMS AND CONDITIONS FOR USE, REPRODUCTION,
+AND DISTRIBUTION
+
+   1. Definitions.
+
+      
+
+"License" shall mean the terms and conditions for use, reproduction, and distribution
+as defined by Sections 1 through 9 of this document.
+
+      
+
+"Licensor" shall mean the copyright owner or entity authorized by the copyright
+owner that is granting the License.
+
+      
+
+"Legal Entity" shall mean the union of the acting entity and all other entities
+that control, are controlled by, or are under common control with that entity.
+For the purposes of this definition, "control" means (i) the power, direct
+or indirect, to cause the direction or management of such entity, whether
+by contract or otherwise, or (ii) ownership of fifty percent (50%) or more
+of the outstanding shares, or (iii) beneficial ownership of such entity.
+
+      
+
+"You" (or "Your") shall mean an individual or Legal Entity exercising permissions
+granted by this License.
+
+      
+
+"Source" form shall mean the preferred form for making modifications, including
+but not limited to software source code, documentation source, and configuration
+files.
+
+      
+
+"Object" form shall mean any form resulting from mechanical transformation
+or translation of a Source form, including but not limited to compiled object
+code, generated documentation, and conversions to other media types.
+
+      
+
+"Work" shall mean the work of authorship, whether in Source or Object form,
+made available under the License, as indicated by a copyright notice that
+is included in or attached to the work (an example is provided in the Appendix
+below).
+
+      
+
+"Derivative Works" shall mean any work, whether in Source or Object form,
+that is based on (or derived from) the Work and for which the editorial revisions,
+annotations, elaborations, or other modifications represent, as a whole, an
+original work of authorship. For the purposes of this License, Derivative
+Works shall not include works that remain separable from, or merely link (or
+bind by name) to the interfaces of, the Work and Derivative Works thereof.
+
+      
+
+"Contribution" shall mean any work of authorship, including the original version
+of the Work and any modifications or additions to that Work or Derivative
+Works thereof, that is intentionally submitted to Licensor for inclusion in
+the Work by the copyright owner or by an individual or Legal Entity authorized
+to submit on behalf of the copyright owner. For the purposes of this definition,
+"submitted" means any form of electronic, verbal, or written communication
+sent to the Licensor or its representatives, including but not limited to
+communication on electronic mailing lists, source code control systems, and
+issue tracking systems that are managed by, or on behalf of, the Licensor
+for the purpose of discussing and improving the Work, but excluding communication
+that is conspicuously marked or otherwise designated in writing by the copyright
+owner as "Not a Contribution."
+
+      
+
+"Contributor" shall mean Licensor and any individual or Legal Entity on behalf
+of whom a Contribution has been received by Licensor and subsequently incorporated
+within the Work.
+
+2. Grant of Copyright License. Subject to the terms and conditions of this
+License, each Contributor hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable copyright license to reproduce, prepare
+Derivative Works of, publicly display, publicly perform, sublicense, and distribute
+the Work and such Derivative Works in Source or Object form.
+
+3. Grant of Patent License. Subject to the terms and conditions of this License,
+each Contributor hereby grants to You a perpetual, worldwide, non-exclusive,
+no-charge, royalty-free, irrevocable (except as stated in this section) patent
+license to make, have made, use, offer to sell, sell, import, and otherwise
+transfer the Work, where such license applies only to those patent claims
+licensable by such Contributor that are necessarily infringed by their Contribution(s)
+alone or by combination of their Contribution(s) with the Work to which such
+Contribution(s) was submitted. If You institute patent litigation against
+any entity (including a cross-claim or counterclaim in a lawsuit) alleging
+that the Work or a Contribution incorporated within the Work constitutes direct
+or contributory patent infringement, then any patent licenses granted to You
+under this License for that Work shall terminate as of the date such litigation
+is filed.
+
+4. Redistribution. You may reproduce and distribute copies of the Work or
+Derivative Works thereof in any medium, with or without modifications, and
+in Source or Object form, provided that You meet the following conditions:
+
+(a) You must give any other recipients of the Work or Derivative Works a copy
+of this License; and
+
+(b) You must cause any modified files to carry prominent notices stating that
+You changed the files; and
+
+(c) You must retain, in the Source form of any Derivative Works that You distribute,
+all copyright, patent, trademark, and attribution notices from the Source
+form of the Work, excluding those notices that do not pertain to any part
+of the Derivative Works; and
+
+(d) If the Work includes a "NOTICE" text file as part of its distribution,
+then any Derivative Works that You distribute must include a readable copy
+of the attribution notices contained within such NOTICE file, excluding those
+notices that do not pertain to any part of the Derivative Works, in at least
+one of the following places: within a NOTICE text file distributed as part
+of the Derivative Works; within the Source form or documentation, if provided
+along with the Derivative Works; or, within a display generated by the Derivative
+Works, if and wherever such third-party notices normally appear. The contents
+of the NOTICE file are for informational purposes only and do not modify the
+License. You may add Your own attribution notices within Derivative Works
+that You distribute, alongside or as an addendum to the NOTICE text from the
+Work, provided that such additional attribution notices cannot be construed
+as modifying the License.
+
+You may add Your own copyright statement to Your modifications and may provide
+additional or different license terms and conditions for use, reproduction,
+or distribution of Your modifications, or for any such Derivative Works as
+a whole, provided Your use, reproduction, and distribution of the Work otherwise
+complies with the conditions stated in this License.
+
+5. Submission of Contributions. Unless You explicitly state otherwise, any
+Contribution intentionally submitted for inclusion in the Work by You to the
+Licensor shall be under the terms and conditions of this License, without
+any additional terms or conditions. Notwithstanding the above, nothing herein
+shall supersede or modify the terms of any separate license agreement you
+may have executed with Licensor regarding such Contributions.
+
+6. Trademarks. This License does not grant permission to use the trade names,
+trademarks, service marks, or product names of the Licensor, except as required
+for reasonable and customary use in describing the origin of the Work and
+reproducing the content of the NOTICE file.
+
+7. Disclaimer of Warranty. Unless required by applicable law or agreed to
+in writing, Licensor provides the Work (and each Contributor provides its
+Contributions) on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
+KIND, either express or implied, including, without limitation, any warranties
+or conditions of TITLE, NON-INFRINGEMENT, MERCHANTABILITY, or FITNESS FOR
+A PARTICULAR PURPOSE. You are solely responsible for determining the appropriateness
+of using or redistributing the Work and assume any risks associated with Your
+exercise of permissions under this License.
+
+8. Limitation of Liability. In no event and under no legal theory, whether
+in tort (including negligence), contract, or otherwise, unless required by
+applicable law (such as deliberate and grossly negligent acts) or agreed to
+in writing, shall any Contributor be liable to You for damages, including
+any direct, indirect, special, incidental, or consequential damages of any
+character arising as a result of this License or out of the use or inability
+to use the Work (including but not limited to damages for loss of goodwill,
+work stoppage, computer failure or malfunction, or any and all other commercial
+damages or losses), even if such Contributor has been advised of the possibility
+of such damages.
+
+9. Accepting Warranty or Additional Liability. While redistributing the Work
+or Derivative Works thereof, You may choose to offer, and charge a fee for,
+acceptance of support, warranty, indemnity, or other liability obligations
+and/or rights consistent with this License. However, in accepting such obligations,
+You may act only on Your own behalf and on Your sole responsibility, not on
+behalf of any other Contributor, and only if You agree to indemnify, defend,
+and hold each Contributor harmless for any liability incurred by, or claims
+asserted against, such Contributor by reason of your accepting any such warranty
+or additional liability. END OF TERMS AND CONDITIONS
+
+APPENDIX: How to apply the Apache License to your work.
+
+To apply the Apache License to your work, attach the following boilerplate
+notice, with the fields enclosed by brackets "[]" replaced with your own identifying
+information. (Don't include the brackets!) The text should be enclosed in
+the appropriate comment syntax for the file format. We also recommend that
+a file or class name and description of purpose be included on the same "printed
+page" as the copyright notice for easier identification within third-party
+archives.
+
+Copyright [yyyy] [name of copyright owner]
+
+Licensed under the Apache License, Version 2.0 (the "License");
+
+you may not use this file except in compliance with the License.
+
+You may obtain a copy of the License at
+
+http://www.apache.org/licenses/LICENSE-2.0
+
+Unless required by applicable law or agreed to in writing, software
+
+distributed under the License is distributed on an "AS IS" BASIS,
+
+WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+
+See the License for the specific language governing permissions and
+
+limitations under the License.
diff --git a/LICENSES/CC0-1.0.txt b/LICENSES/CC0-1.0.txt
new file mode 100644
index 0000000000000000000000000000000000000000..a343ccd4335f66ace3f9a83dfff02212a84ef4f2
--- /dev/null
+++ b/LICENSES/CC0-1.0.txt
@@ -0,0 +1,119 @@
+Creative Commons Legal Code
+
+CC0 1.0 Universal CREATIVE COMMONS CORPORATION IS NOT A LAW FIRM AND DOES
+NOT PROVIDE LEGAL SERVICES. DISTRIBUTION OF THIS DOCUMENT DOES NOT CREATE
+AN ATTORNEY-CLIENT RELATIONSHIP. CREATIVE COMMONS PROVIDES THIS INFORMATION
+ON AN "AS-IS" BASIS. CREATIVE COMMONS MAKES NO WARRANTIES REGARDING THE USE
+OF THIS DOCUMENT OR THE INFORMATION OR WORKS PROVIDED HEREUNDER, AND DISCLAIMS
+LIABILITY FOR DAMAGES RESULTING FROM THE USE OF THIS DOCUMENT OR THE INFORMATION
+OR WORKS PROVIDED HEREUNDER.
+
+Statement of Purpose
+
+The laws of most jurisdictions throughout the world automatically confer exclusive
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+
+For these and/or other purposes and motivations, and without any expectation
+of additional consideration or compensation, the person associating CC0 with
+a Work (the "Affirmer"), to the extent that he or she is an owner of Copyright
+and Related Rights in the Work, voluntarily elects to apply CC0 to the Work
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+her Copyright and Related Rights in the Work and the meaning and intended
+legal effect of CC0 on those rights.
+
+1. Copyright and Related Rights. A Work made available under CC0 may be protected
+by copyright and related or neighboring rights ("Copyright and Related Rights").
+Copyright and Related Rights include, but are not limited to, the following:
+
+i. the right to reproduce, adapt, distribute, perform, display, communicate,
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+vi. database rights (such as those arising under Directive 96/9/EC of the
+European Parliament and of the Council of 11 March 1996 on the legal protection
+of databases, and under any national implementation thereof, including any
+amended or successor version of such directive); and
+
+vii. other similar, equivalent or corresponding rights throughout the world
+based on applicable law or treaty, and any national implementations thereof.
+
+2. Waiver. To the greatest extent permitted by, but not in contravention of,
+applicable law, Affirmer hereby overtly, fully, permanently, irrevocably and
+unconditionally waives, abandons, and surrenders all of Affirmer's Copyright
+and Related Rights and associated claims and causes of action, whether now
+known or unknown (including existing as well as future claims and causes of
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+
+3. Public License Fallback. Should any part of the Waiver for any reason be
+judged legally invalid or ineffective under applicable law, then the Waiver
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+was applied by Affirmer to the Work. Should any part of the License for any
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+partial invalidity or ineffectiveness shall not invalidate the remainder of
+the License, and in such case Affirmer hereby affirms that he or she will
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+
+   4. Limitations and Disclaimers.
+
+a. No trademark or patent rights held by Affirmer are waived, abandoned, surrendered,
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+
+c. Affirmer disclaims responsibility for clearing rights of other persons
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+d. Affirmer understands and acknowledges that Creative Commons is not a party
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diff --git a/LICENSES/GPL-3.0-or-later.txt b/LICENSES/GPL-3.0-or-later.txt
new file mode 100644
index 0000000000000000000000000000000000000000..e142a525bd3fcc4eb1964d6b6b9a0434eee11d89
--- /dev/null
+++ b/LICENSES/GPL-3.0-or-later.txt
@@ -0,0 +1,625 @@
+GNU GENERAL PUBLIC LICENSE
+
+Version 3, 29 June 2007
+
+Copyright © 2007 Free Software Foundation, Inc. <https://fsf.org/>
+
+Everyone is permitted to copy and distribute verbatim copies of this license
+document, but changing it is not allowed.
+
+Preamble
+
+The GNU General Public License is a free, copyleft license for software and
+other kinds of works.
+
+The licenses for most software and other practical works are designed to take
+away your freedom to share and change the works. By contrast, the GNU General
+Public License is intended to guarantee your freedom to share and change all
+versions of a program--to make sure it remains free software for all its users.
+We, the Free Software Foundation, use the GNU General Public License for most
+of our software; it applies also to any other work released this way by its
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+this when it starts in an interactive mode:
+
+<program> Copyright (C) <year> <name of author>
+
+This program comes with ABSOLUTELY NO WARRANTY; for details type `show w'.
+
+This is free software, and you are welcome to redistribute it under certain
+conditions; type `show c' for details.
+
+The hypothetical commands `show w' and `show c' should show the appropriate
+parts of the General Public License. Of course, your program's commands might
+be different; for a GUI interface, you would use an "about box".
+
+You should also get your employer (if you work as a programmer) or school,
+if any, to sign a "copyright disclaimer" for the program, if necessary. For
+more information on this, and how to apply and follow the GNU GPL, see <https://www.gnu.org/licenses/>.
+
+The GNU General Public License does not permit incorporating your program
+into proprietary programs. If your program is a subroutine library, you may
+consider it more useful to permit linking proprietary applications with the
+library. If this is what you want to do, use the GNU Lesser General Public
+License instead of this License. But first, please read <https://www.gnu.org/
+licenses /why-not-lgpl.html>.
diff --git a/README.md b/README.md
index 2e0c706cf2fa02b54180403161b1eda1515fbe44..334a4cc283696f0f88efa6606a10b94a4b784733 100644
--- a/README.md
+++ b/README.md
@@ -1,4 +1,10 @@
+<--
+SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+
+SPDX-License-Identifier: CC0-1.0
+-->
+
 A bunch of simple C programs which only use the standard library (and a bit of
 OpenMP as well).
 
-GLib is only required for its testing interface.
\ No newline at end of file
+GLib is only required for its testing interface.
diff --git a/lib/meson.build b/lib/meson.build
index e9a7abfdd30c9f8324fc65193c2041dc461e4a7b..40709a6eb9cc1f080154203434d01ae7b46919bd 100644
--- a/lib/meson.build
+++ b/lib/meson.build
@@ -1,2 +1,6 @@
+# SPDX-FileCopyrightText: 2018-2019 Bruce Cowan
+#
+# SPDX-License-Identifier: CC0-1.0
+
 subdir('utils')
 subdir('types')
diff --git a/lib/types/array.c b/lib/types/array.c
index 97c9cdc3af932132eed9734267c1928e0f7ef1de..9dcf09d8e34db9596fdb9522c56b1096abffedbe 100644
--- a/lib/types/array.c
+++ b/lib/types/array.c
@@ -1,18 +1,5 @@
-/* array.c
- *
- * Copyright 2018 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/types/array.h b/lib/types/array.h
index 25c432ac74835630783123fc3785abfc16351218..3207ad191105c2a72b57c3e91de270f814768508 100644
--- a/lib/types/array.h
+++ b/lib/types/array.h
@@ -1,18 +1,5 @@
-/* array.h
- *
- * Copyright 2018 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/types/hashtable.c b/lib/types/hashtable.c
index a7c2631b5c1de4d5e11cbc9050f9478399b855fc..a0efb443d67cbac8459695a7783e664b3bc595a0 100644
--- a/lib/types/hashtable.c
+++ b/lib/types/hashtable.c
@@ -1,18 +1,5 @@
-/* hashtable.c
- *
- * Copyright 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/types/hashtable.h b/lib/types/hashtable.h
index c263c6464c35b2bae73a032a42376d1f83efd519..3597e1f15a06c6202ad860074755cfba94096ee4 100644
--- a/lib/types/hashtable.h
+++ b/lib/types/hashtable.h
@@ -1,18 +1,5 @@
-/* hashtable.h
- *
- * Copyright 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/types/meson.build b/lib/types/meson.build
index 6ffcb0cf1e65873714b52f37c0c3d46f7a248b1b..7033f7599c35def2dc45508110fadfe542e5eba0 100644
--- a/lib/types/meson.build
+++ b/lib/types/meson.build
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2018-2019 Bruce Cowan <bruce@bcowan.me.uk>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 types_src = ['array.c', 'hashtable.c', 'slist.c']
 types_lib = library('types', types_src, dependencies: [libm, utils_dep])
 types_dep = declare_dependency(link_with: types_lib, include_directories: '.')
diff --git a/lib/types/slist.c b/lib/types/slist.c
index 300c53f1ebe347ee0bac622a025602a0b22a9815..1af596c4fe6046c4c15391d6b0f964987e022da7 100644
--- a/lib/types/slist.c
+++ b/lib/types/slist.c
@@ -1,18 +1,5 @@
-/* slist.c
- *
- * Copyright 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/types/slist.h b/lib/types/slist.h
index dc2ad706bb567a0e23170a5c3dca17991e2da296..452eff52c05c0f9eb6f6091facdb8cebde885e57 100644
--- a/lib/types/slist.h
+++ b/lib/types/slist.h
@@ -1,18 +1,5 @@
-/* slist.h
- *
- * Copyright 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/types/types.h b/lib/types/types.h
index 66aeaf1b7357d5c26bd0e96906d19e3322ed6f42..85639d0cbd7c4ff374b16a66cfaa6c2d6f040d1c 100644
--- a/lib/types/types.h
+++ b/lib/types/types.h
@@ -1,18 +1,5 @@
-/* types.h
- *
- * Copyright 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/utils/mem.c b/lib/utils/mem.c
index e5675126824fdbc83cd742e129c7278b6dfbbc1a..965b4c5cb90df129699acff66da9f34796fc8de3 100644
--- a/lib/utils/mem.c
+++ b/lib/utils/mem.c
@@ -1,26 +1,9 @@
-/* mem.c
- *
- * Copyright 2018, 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2018, 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
 
-#ifdef HAVE_REALLOCARRAY
-  #define _GNU_SOURCE
-#endif
-
 #include "config.h"
 #include "mem.h"
 
diff --git a/lib/utils/mem.h b/lib/utils/mem.h
index 335fab2a99ca543dab59fc9a6d225e400471d527..cfbc898a140abc6e4d645ee659b7f01dbe7edca7 100644
--- a/lib/utils/mem.h
+++ b/lib/utils/mem.h
@@ -1,18 +1,5 @@
-/* mem.h
- *
- * Copyright 2018 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2018, 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/utils/meson.build b/lib/utils/meson.build
index 94f97d86558b72165c7193f2ee0cb6ce8111bb1f..9c6dabc78f58c4fe55802cc9ec9ed745a5755253 100644
--- a/lib/utils/meson.build
+++ b/lib/utils/meson.build
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2019 Bruce Cowan
+#
+# SPDX-License-Identifier: CC0-1.0
+
 utils_lib = library('utils', ['mem.c', 'utils.c'], dependencies: config_dep)
 utils_dep = declare_dependency(link_with: utils_lib,
   include_directories: '.')
diff --git a/lib/utils/utils.c b/lib/utils/utils.c
index 2ee64a17afcab142d6d2906536ffb0371398b44d..43d4ba36360d667929aed462dc0a59608083a17a 100644
--- a/lib/utils/utils.c
+++ b/lib/utils/utils.c
@@ -1,18 +1,5 @@
-/* utils.c
- *
- * Copyright 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/lib/utils/utils.h b/lib/utils/utils.h
index 765ded804643631be84a0343e4ce79b82d17659c..7cca9730b757e8a771ef5dbc4eedfe901de569b8 100644
--- a/lib/utils/utils.h
+++ b/lib/utils/utils.h
@@ -1,18 +1,5 @@
-/* utils.h
- *
- * Copyright 2019 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *   http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/meson.build b/meson.build
index 2ede9cb596a6e78430fc9b288a587b1c3a9b972e..53d8b4c645aae1d81a5c5ab9e99652ad1f55a027 100644
--- a/meson.build
+++ b/meson.build
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2018, 2019 Bruce Cowan
+#
+# SPDX-License-Identifier: CC0-1.0
+
 project('stdlib', 'c',
   default_options: ['warning_level=3', 'c_std=gnu99'])
 
diff --git a/src/add.c b/src/add.c
index 55e1935dc774e1eb7c36ee227ef8dc7b55900060..cc0fbb81caa97b336aa812de28ca79f2358f1dff 100644
--- a/src/add.c
+++ b/src/add.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 #include "utils.h"
diff --git a/src/angle.c b/src/angle.c
index f06b9687f04877cd8f3a50728d16ebe755109211..12e82d0f6e081b9c0cfab44ec4050b5974e59153 100644
--- a/src/angle.c
+++ b/src/angle.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <tgmath.h>
 
diff --git a/src/array-length.c b/src/array-length.c
index 3cdd23719701a0870e7ddd3ed6cfb2c116f4d10b..c4144d423ee946e37900e017aee555a9a730af4e 100644
--- a/src/array-length.c
+++ b/src/array-length.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 #include <array.h>
diff --git a/src/binary.c b/src/binary.c
index d3d98627644032b4063db1a4a4e6f92cecbc68b8..f363d050c59ac2794d9bc17c2597a901f90a62cf 100644
--- a/src/binary.c
+++ b/src/binary.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 static int list[] = { 8, 11, 17, 22, 29, 38, 51, 58, 65, 67, 74, 81, 87, 90, 96, 97 };
diff --git a/src/binary2.c b/src/binary2.c
index 0a8189a730860c9019fe4f52401b0125c2264156..0e24d011ecad720fa91ee6e8b9861ea4996a9a52 100644
--- a/src/binary2.c
+++ b/src/binary2.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 
diff --git a/src/complex.c b/src/complex.c
index 8582c07f2b8bc4853258e2d85ed1ae015c9adaa4..1345057616c2ce4b4a978eff8094402a8e92788d 100644
--- a/src/complex.c
+++ b/src/complex.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <tgmath.h>
 
diff --git a/src/doubles.c b/src/doubles.c
index e8defaf6b86161fe203bf347c25d8604ac7c30c4..cd7fcf67be219736b187a7920d312c0888654fcc 100644
--- a/src/doubles.c
+++ b/src/doubles.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 
diff --git a/src/einstein.c b/src/einstein.c
index 6f4dad4f9f04b10a60733d137e656e4bb54bed0e..68d07bdb7b2d7db626b505516ce39ec70b619a8c 100644
--- a/src/einstein.c
+++ b/src/einstein.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 
diff --git a/src/fgets.c b/src/fgets.c
index a60cab34257247b3d3cbdf195f69f3580bdecb69..8d18a88b48d8384cdca93e0957cb38fdab83ecf6 100644
--- a/src/fgets.c
+++ b/src/fgets.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 int
diff --git a/src/fib.c b/src/fib.c
index 61b078ee5b39d22f88748d9ddcb8eb791025f701..5f6000175eb7b424480245b58ed8a55ead18eb35 100644
--- a/src/fib.c
+++ b/src/fib.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <inttypes.h>
 #include <stdio.h>
 
diff --git a/src/fixed-formats.c b/src/fixed-formats.c
index 06235acbad9e4877c071fde7ed4e6c841a25a96e..2f9a78dca259c431808b640cc7f198a9c4e6fdd4 100644
--- a/src/fixed-formats.c
+++ b/src/fixed-formats.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <inttypes.h>
 #include <stdio.h>
 #include <stdint.h>
diff --git a/src/fixed-sizeof.c b/src/fixed-sizeof.c
index a0d00728b96ba49ba616988ab6705bcbd4705ab3..d8c85826e71c7553d04f3a62f41a57cef432fc8f 100644
--- a/src/fixed-sizeof.c
+++ b/src/fixed-sizeof.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <stdint.h>
 
diff --git a/src/gcd.c b/src/gcd.c
index c30bed3bbe98a5964b2ae9c3ad6ae3b9554168e4..986ce1bedc95d9de9e70727135fb4a9cf6fb6735 100644
--- a/src/gcd.c
+++ b/src/gcd.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 
diff --git a/src/getchar.c b/src/getchar.c
index 86e49d9a064fd69fb33792ee2cfa1b03487440d0..80e751119420e2eccd970f94418275d4c140a82d 100644
--- a/src/getchar.c
+++ b/src/getchar.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <inttypes.h>
 #include <stdint.h>
 #include <stdio.h>
diff --git a/src/hashtable-test.c b/src/hashtable-test.c
index 392cade6374d154214d424d933d275d39319089c..c201142f567d7db7fb5e6c2f8d45c35f8642998b 100644
--- a/src/hashtable-test.c
+++ b/src/hashtable-test.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018, 2019 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
diff --git a/src/kepler.c b/src/kepler.c
index 7da4f95d518c0e30a2b457a4ba18b88aae53cbca..f10441c21255eaf7c48e9e49f51a9781503aaa72 100644
--- a/src/kepler.c
+++ b/src/kepler.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <tgmath.h>
diff --git a/src/list-test.c b/src/list-test.c
index 31333b530da63956d8a63ba6b0f301125436a9ee..8694c45f06b4a7f15df4d1e99818cdda64f315a3 100644
--- a/src/list-test.c
+++ b/src/list-test.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <slist.h>
 
 #include <stdio.h>
diff --git a/src/meson.build b/src/meson.build
index 46eeab575f94224bb246d54f529fbc7198a11182..10713c14ab8e6674a3ee68c4e1dab7be0546a0c3 100644
--- a/src/meson.build
+++ b/src/meson.build
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2018, 2019 Bruce Cowan <bruce@bcowan.me.uk>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 executable('add', 'add.c', dependencies: utils_dep)
 executable('angle', 'angle.c', dependencies: libm)
 executable('array-length', 'array-length.c', dependencies: types_dep)
diff --git a/src/next.c b/src/next.c
index 027b5bfaf49f5ab12b445f574697a516a3f24b90..3c1328efa8a62125c088636d59641264646d19a7 100644
--- a/src/next.c
+++ b/src/next.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <tgmath.h>
diff --git a/src/openmp/meson.build b/src/openmp/meson.build
index 6031942bf6bf0e39407d498c2db129d5ae77de45..50ce3ab0285c99f67bebc54cb9c44aeba85b457b 100644
--- a/src/openmp/meson.build
+++ b/src/openmp/meson.build
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2018 Bruce Cowan
+#
+# SPDX-License-Identifier: CC0-1.0
+
 executable('pi', 'pi.c', dependencies: [openmp_dep, libm])
 executable('simd', 'simd.c', dependencies: openmp_dep)
 executable('taylor', 'taylor.c', dependencies: openmp_dep)
diff --git a/src/openmp/pi.c b/src/openmp/pi.c
index 6d2384f848724a5d7790b35dc26cec0435d64d3b..4a00f91ca65d21c0d0be59325a067654bbde8c42 100644
--- a/src/openmp/pi.c
+++ b/src/openmp/pi.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <tgmath.h>
diff --git a/src/openmp/simd.c b/src/openmp/simd.c
index ae48262712b1df82823da2b4f9ee198b070a3354..030b436521c71c337bc17f8b508a424d56962b91 100644
--- a/src/openmp/simd.c
+++ b/src/openmp/simd.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 static const int N = 32;
diff --git a/src/openmp/taylor.c b/src/openmp/taylor.c
index 28df1ddd083c1c2f3f7a68c455449a1391b2c18b..5b7a6985e44589c38faf30b3b65c10e9f0176cdd 100644
--- a/src/openmp/taylor.c
+++ b/src/openmp/taylor.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <stdio.h>
 
 #include <omp.h>
diff --git a/src/openmp/threads.c b/src/openmp/threads.c
index 7963ce78be6209626d6e36119aadc164c1145913..9fcb3962a9322dd9bf1967df9d31aec12b9457bb 100644
--- a/src/openmp/threads.c
+++ b/src/openmp/threads.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 #include <omp.h>
diff --git a/src/parrot.c b/src/parrot.c
index c502a30b58de1e790a3af576e9e7d31766e69146..d8bac5d4cbcde920cd9ef737532214f8ee2636c3 100644
--- a/src/parrot.c
+++ b/src/parrot.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
diff --git a/src/pthread/meson.build b/src/pthread/meson.build
index bc22c6f9c5dbfe65b2d4fce31277817714c1b2a3..d8d7939573f914c534dfc8f717892f40bf6d295c 100644
--- a/src/pthread/meson.build
+++ b/src/pthread/meson.build
@@ -1,2 +1,6 @@
+# SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 executable('thread-incr', 'thread-incr.c',
            dependencies: [thread_dep, utils_dep])
diff --git a/src/pthread/thread-incr.c b/src/pthread/thread-incr.c
index 4908e1309e875e123a2964e7bf63a5f3ed6f077a..c413c52833572b7b1bc7125e93b9642f29d79dab 100644
--- a/src/pthread/thread-incr.c
+++ b/src/pthread/thread-incr.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <stdio.h>
 #include <stdlib.h>
 
diff --git a/src/sizeof.c b/src/sizeof.c
index 9708d2b72a5df4ec977d04c161ab758a49446ff1..150576baec9543520a1b9fce2143e335624a7126 100644
--- a/src/sizeof.c
+++ b/src/sizeof.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <complex.h>
 #include <stdio.h>
 #include <stdint.h>
diff --git a/src/snprintf.c b/src/snprintf.c
index 9c11fd973f0d4a06c6c712010718928033d6f73e..2f62bc2fd1fd28f2b2255a1bd0aa586c3ad132cb 100644
--- a/src/snprintf.c
+++ b/src/snprintf.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 #ifdef __GNUC__
diff --git a/src/sockets/meson.build b/src/sockets/meson.build
index 70e43041b5b6e52449494850c02ac8b0018090e0..dfb0264c84dc8526dd2cae8828fcc3139ada0a42 100644
--- a/src/sockets/meson.build
+++ b/src/sockets/meson.build
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 if host_machine.system() == 'windows'
     udp_server_src = ['udp-server-win.c']
 else
diff --git a/src/sockets/udp-server-win.c b/src/sockets/udp-server-win.c
index a270016d4184e9b9e8186b65a9eb19ddac92df37..9921cc567f800075b8cca6b6a2072c4bc03cdef9 100644
--- a/src/sockets/udp-server-win.c
+++ b/src/sockets/udp-server-win.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
diff --git a/src/sockets/udp-server.c b/src/sockets/udp-server.c
index 94c5b0955e5aa1ab3e6828dbe9f20119884c59ea..b371319195db6a27f2304d06ebf903c5efe670a6 100644
--- a/src/sockets/udp-server.c
+++ b/src/sockets/udp-server.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2019 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 #include <stdbool.h>
 #include <stdint.h>
 #include <stdio.h>
diff --git a/src/strtol.c b/src/strtol.c
index 5964d43dd63e7ff33dda5bb968c343c46c879072..1f9222f557224ac1a18e317faa73ea176666b652 100644
--- a/src/strtol.c
+++ b/src/strtol.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
diff --git a/src/taylor.c b/src/taylor.c
index 721ad07d2a819761840f43b33fbf229613b02143..c689fc93e43d7400960c3b6bc81905fddbed06b6 100644
--- a/src/taylor.c
+++ b/src/taylor.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 #include <time.h>
 
diff --git a/src/winter.c b/src/winter.c
index dc3525cceb4f4aab40e21b7c128747e5e1f067a2..59ae8688f3cb4aba1675e48d5621494ed25bdb5c 100644
--- a/src/winter.c
+++ b/src/winter.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: GPL-3.0-or-later
+ */
+
 /********************************************************
  * Idea from S5 programming task, converted from BASIC. *
  ********************************************************/
diff --git a/src/world.c b/src/world.c
index cf8ccf8facdbd7f71c14c1fc19bbeb3ff8d97c40..dead9b5515f8e54160fe9ed08050c038e5be4058 100644
--- a/src/world.c
+++ b/src/world.c
@@ -1,3 +1,9 @@
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+ *
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
 #include <stdio.h>
 
 int
diff --git a/test/array-average.c b/test/array-average.c
index e81bb27664ea7d443c7a3199fe0da4e6157418eb..fa83be6aa235bdd325215c578b160c205c018950 100644
--- a/test/array-average.c
+++ b/test/array-average.c
@@ -1,18 +1,5 @@
-/* average.c
- *
- * Copyright 2018 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/test/array-basic.c b/test/array-basic.c
index aede24f9a357d8786f0584c8919f2beeb7f0195c..26307f2ee5f04b3a775f9a01209ee21b20787b25 100644
--- a/test/array-basic.c
+++ b/test/array-basic.c
@@ -1,18 +1,5 @@
-/* basic.c
- *
- * Copyright 2018 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/test/array-empty.c b/test/array-empty.c
index d4d590a9ac5287b1c247458424f81060e7089a2c..91a60ed80656721a6118e83901e230719e31665c 100644
--- a/test/array-empty.c
+++ b/test/array-empty.c
@@ -1,18 +1,5 @@
-/* empty.c
- *
- * Copyright 2018 Bruce Cowan <bruce@bcowan.me.uk>
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- *     http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
+/*
+ * SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
  *
  * SPDX-License-Identifier: Apache-2.0
  */
diff --git a/test/meson.build b/test/meson.build
index f60fcc48afae21dc232ef492f8c6f0f1008e7921..651b6cb98a49c8dfe936fe966d9959b3110e19e2 100644
--- a/test/meson.build
+++ b/test/meson.build
@@ -1,3 +1,7 @@
+# SPDX-FileCopyrightText: 2018 Bruce Cowan <bruce@bcowan.me.uk>
+#
+# SPDX-License-Identifier: CC0-1.0
+
 avg = executable('array-average',
                  'array-average.c',
                  dependencies: [types_dep, glib_dep])