Licensing
Everything in this repository is licensed Creative Commons
Attribution-ShareAlike 4.0 International (CC BY-SA 4.0) unless stated otherwise below.
The full legal text is in LICENSE.
You may copy, redistribute, adapt, and build on this material, including commercially, provided you give attribution and license your adaptations under the same terms.
Why ShareAlike
The choice between BY and BY-SA is not a matter of taste here; it follows from the founding thesis §3.
The strongest claim in §3 is that giving the curriculum away denies a test-prep industry any room to form between us and the candidate. Plain BY undercuts exactly that. A prep company could take the whole curriculum, wrap it, keep its additions closed, and build the layer the model exists to prevent.
ShareAlike still permits anyone to charge for the material — that is deliberate — but it prevents building private differentiation on top of it. Anything added comes back. That removes most of the incentive to construct a closed prep layer, while leaving the open ecosystem intact.
Share-alike also does the compliance work §3 relies on. ISO/IEC 17024 clause 5.2.3(d) forbids requiring our own training as an exclusive prerequisite where equivalent alternatives exist. Open licensing manufactures that alternative permanently, and share-alike keeps the alternatives open rather than allowing them to be enclosed.
The usual objection — that employers will not adopt material they must reopen — is weaker than it sounds. Share-alike obligations attach to distribution, not to internal use. An employer adapting the curriculum for its own technicians triggers nothing.
Exceptions
FAA material is public domain and not ours to license. The ACS element spine (the element inventory) and other files reproduce element text from FAA-S-ACS-1, a work of the United States Government. That text carries no copyright and is not covered by CC BY-SA. What is licensed here is our compilation, structure, identifiers, and commentary — not the underlying government text. The same applies to any quoted regulation or FAA handbook material.
Software carries its own license: Apache-2.0. CC licenses are not intended for software.
Founder decision, 23 September 2026: the scheme's code is licensed under the Apache License,
Version 2.0, whose text is LICENSE-CODE. A file it covers says so in an
SPDX-License-Identifier: Apache-2.0 header. The item generators are the first code
published (industries/aviation-maintenance/assessment/item-generators.py), because 32
elements are served by a generator rather than stored items and the open assessment policy
publishes the generator itself. Scripts not yet published — checks, builders, fetchers and the
export tool — are internal tooling until a file carries the header and an export names it.
Updated 23 September 2026. This read: "No software license has yet been stated for any of them. They are internal tooling, and until a license is chosen they are not licensed for reuse." A license has now been chosen.
Updated 22 September 2026. This read: "Any code added to this repository — an item authoring system, tooling, scoring implementations — will carry a separate software license, stated at the point it is added." Code was added and no license was stated with it; that is the position recorded above, and choosing a license is still open.
Assessment items are licensed CC BY-SA 4.0, like everything else. Items, answer keys and
item-level statistics are held in industries/*/assessment/items/ and are published
(the open assessment policy, founder decision of 27 August 2026). The generators are
code, and carry Apache-2.0 as above; the items they produce are assessment material like any
other. (Until 23 September 2026 this sentence listed generators with the items, under CC BY-SA.)
Changed. This previously said items were unlicensed, undistributed, and the reason this repository is permanently private. Thesis §3 says everything that can be copied is free, and an item bank can be copied — the exception was never argued for. The repository stays private pending a history audit for candidate data, which is now the only reason for it.
Updated 22 September 2026. The history audit has been run and is clean (recorded on 27 August 2026), and the founder decided on 27 August 2026 that the repository stays private regardless. Any future change needs a fresh audit and a fresh decision.
Attributing this work
Based on work by Standards, licensed CC BY-SA 4.0. Source: https://github.com/robcohen/Standards
Attribution must not imply that we endorse you or your adaptation, and must not suggest that an adaptation confers any advantage in our assessment — the latter is a requirement of ISO/IEC 17024 clause 5.2.3(c), not a courtesy.
Contributing
Contributions are accepted on the same terms. Because relicensing contributed work requires every contributor's consent, this license is effectively permanent from the first accepted contribution. That is why it was settled before curriculum production began (the founding thesis §9).