Licence
Copyright 2026 Girish Kumar Krishnan.
Two licences, split by what each thing is for. Both are permissive; they differ on one clause, and the difference is deliberate.
| what | licence | what it means |
|---|---|---|
the apps — scale_app/, solar_system/, time_app/, orrery/ | CC BY-SA 4.0 | copy, share, modify, translate. Credit required. Anything derived from them must stay under the same licence. |
THE_STANDARD.md and ATTENTION_RUBRIC.md | CC BY 4.0 | copy, share, modify, embed in your own documents. Credit required. No obligation to license your work alike. |
MISSION.md, and the prose on the website | all rights reserved | not licensed for reuse |
infrastructure/ | CC BY-SA 4.0, as above | the scripts and configuration behind the site and its mail |
Why the apps are ShareAlike and the standard is not
The apps carry ShareAlike so they cannot be enclosed. Take How Far?, improve it, translate it, put it on thirty school laptops — all fine, no permission needed. Take it, bolt advertising onto it and ship it closed — not fine, and now clearly not fine, which is the point. Anyone doing that is not merely impolite, they are in breach.
The standard deliberately has no ShareAlike, because a standard is worth something only if other people adopt it. If a school wants the twelve signs in its own app-selection policy, ShareAlike would drag that whole policy under this licence, and that friction is exactly what makes somebody not bother. The standard is more useful spread than owned. Take it, put your name next to ours, and use it on us.
What is not licensed
The name. "Prosocial Apps", How Big?, How Far?, How Long? and The Long Way Round are not covered by either licence. You may fork the work; you may not present the result as ours. This is the ordinary trademark carve-out that open licences are usually paired with, and it is the part that protects readers rather than us: somebody should be able to tell whether they are looking at the thing that publishes its own failing marks.
Third-party material keeps its own terms, and none of it is ours to relicense:
- The 16 photographs in
solar_system/images/are NASA and JPL imagery, each recorded insolar_system/images/CREDITS.jsonwith its title, NASA identifier, originating centre, date and source URL. NASA imagery is generally free of copyright; the credits are kept per-image so anybody can check a specific one rather than trust a blanket claim. - The three font families carried by the website — Fraunces, Literata and Source Sans 3 — are under the SIL Open Font License 1.1. Copyright lines and sources are in
infrastructure/website/fonts/NOTICE.md, taken from each project's own licence file.
Attribution
Enough to satisfy either licence:
Based on Prosocial Apps by Girish Kumar Krishnan — https://prosocial-apps.org — licensed CC BY-SA 4.0 (or CC BY 4.0 for the standard and the rubric).
A note on CC for the apps
Creative Commons advise against CC licences for software, and that advice is sound where it applies: compiled programs, linking, patent grants, the gap between source and binary. None of that is in play here. Each app is a single HTML file that is its own source, with nothing to compile and nothing to link, and the people most likely to copy one are teachers and parents, who know what CC BY-SA means and do not know what GPL means. That was the trade, made on purpose. GPL-3.0 would give the same copyleft with machinery this does not need.