1. Photography
Every image below was licence-checked against the source page before it shipped. Where a licence requires attribution, the author, licence, and our modification are named.
MRSA micrograph — Step 1 hero
- Subject: colorized scanning electron micrograph of methicillin-resistant Staphylococcus aureus with a dead human neutrophil.
- Credit: NIAID (National Institute of Allergy and Infectious Diseases).
- Licence: CC BY 2.0.
- Source: Wikimedia Commons.
- Modified: yes — cropped, and duotoned to the brand palette.
12-lead electrocardiogram — Step 2 CK hero
- Subject: a 12-lead ECG as recorded in clinical practice.
- Credit: Peter H Charlton.
- Licence: CC BY 4.0.
- Source: Wikimedia Commons.
- Modified: yes — the machine-diagnosis header was cropped away, the frame recropped, and the image duotone-inverted so the chart paper reads as ink.
- Note: the original tracing is abnormal. It is used here as a graphic, and is never presented as a normal ECG.
Laennec stethoscopes — Contact page hero
- Subject: four monaural stethoscopes designed by René Laennec, 19th century.
- Credit: Wellcome Collection.
- Licence: CC BY 4.0.
- Source: Wellcome Collection.
- Modified: yes — inverted so the studio backdrop reads as ink, recropped with the canvas extended on both sides, and duotoned to the brand palette.
Wellcome Institute reading room — Pricing page hero
- Subject: “The Reading Room of the Wellcome Institute.”
- Credit: Wellcome Collection.
- Licence: CC BY 4.0.
- Source: Wellcome Collection.
- Modified: yes — cropped to the upper gallery (leaving out the anatomical print below it), and duotoned to the brand palette.
Brain tractography — News page hero
- Subject: “Brain tractography”, an unfolded map of the brain's fibre pathways.
- Credit: Katja Heuer and Roberto Toro, Wellcome Collection.
- Licence: CC BY 4.0.
- Source: Wellcome Collection.
- Modified: yes — cropped to the fibres inside the rendering, and duotoned to the brand palette.
Public-domain and CC0 photography
Each of these was recropped and duotoned to the brand palette; the engravings were also inverted so the paper reads as ink.
- About: membranous labyrinth of the right side, Plate I in C. H. Burnett, A Text-Book on Diseases of the Ear, Nose and Throat (1901) — Internet Archive Book Images, public domain.
- Support: microscope, Claude-Siméon Passemant, ca. 1750 — The Metropolitan Museum of Art, Open Access (CC0).
- Legal: the National Library of Medicine's main reading room, ca. 1962 — National Library of Medicine, no known copyright restrictions.
- Page not found: J. C. Saunders, Anatomy of the Ear, 1806 — Wellcome Collection, Public Domain Mark.
- Error page: cancer cells under darkfield microscopy, Dr. Cecil Fox, 1987 — National Cancer Institute, public domain.
2. Typography
- Manrope, by Mikhail Sharanda — used for the wordmark, headings, and interface. Licensed under the SIL Open Font License 1.1.
3. Icons
- Lucide — the interface icon set, used under the ISC licence.
The Utricle mark, wordmark, and the exam-interface rebuild are our own work and are not covered by any of the licences above. See Copyright & Intellectual Property.
4. Open-source software
Utricle is built on the work of a great many people who gave it away. The principal components:
- React and Next.js — the application framework (MIT).
- Tailwind CSS — the styling system (MIT).
- Radix UI — accessible interface primitives (MIT).
- Prisma — the database toolkit (Apache 2.0).
- Auth.js — authentication (ISC).
- PostgreSQL and Redis — data and cache.
- TanStack Query, Recharts, Tiptap, Zod, and a long tail of smaller libraries, each under its own permissive licence.
A complete dependency manifest with exact versions and licences is available on request from our contact form.
5. Corrections
If you are the author of something used here and the credit is wrong, incomplete, or missing — or if you would rather we stopped using it — write to our contact form. We will correct it or remove the work promptly, and we will not ask you to prove your case first.