Petits Signes icon: a white hand on a terracotta tile.Petits Signes icon: a white hand on a terracotta tile.
2026 · Open source

petitsignes.cat

A free, open-source website that teaches basic Catalan Sign Language (LSC) and Spanish Sign Language (LSE) vocabulary to families and carers of babies aged 6 to 24 months.

Role
Design, development and content
Launched
Stack
  • Astro
  • React
  • TypeScript
  • Tailwind CSS
  • Zod

Visit websiteSource code

The challenge

A baby understands a lot long before they can speak. Between 6 and 24 months they still can’t say what they want, and whoever is looking after them doesn’t really know what is wrong either. Bimodal communication helps: you talk to them and, at the same time, make the sign for the word. It isn’t about teaching them a new language all at once; it is about giving them a shortcut so that their hands get there before their voice. By around 8 or 9 months they already have enough motor control to say “more”, “milk” or “it hurts” with a gesture, many months before they can pronounce it.

The resources I found were paid: courses, apps and packs of cards. What was missing was a free tool that is easy to use for someone who looks after a baby all day and has no time to learn anything complicated.

What I did

I designed, built and maintain petitsignes.cat on my own, from start to finish.

  • Verified content. 194 signs from everyday life with a baby (eating, sleeping, more, mum, goodbye) in Catalan Sign Language (LSC) and Spanish Sign Language (LSE). Each one comes from an official source: the CNSE’s DILSE for LSE and the Generalitat’s Vocabulari bàsic with FESOCA for LSC. No gesture is invented or approximated: if there is no verifiable source for a word, the card says so instead of filling the gap.
  • Static site. Astro with React islands and strict TypeScript, Tailwind CSS, content validated with Zod and in-browser search with Fuse.js. No backend and no accounts: progress is saved in the browser, behind a storage interface that lets me swap the implementation without rewriting the app.
  • Genuinely accessible. WCAG 2.2 AA: full keyboard navigation, AA contrast and respect for prefers-reduced-motion.
  • Secure and private. A strict Content Security Policy generated at build time, with every inline script and style signed with SHA-256 and no unsafe-inline. Zero personal data: the only metric is an anonymous, aggregated count.
  • Measured quality. Lighthouse scores of 95 or more in all four categories, with budgets that make continuous integration fail if anything gets worse, plus unit and end-to-end tests with accessibility checks.

Who it is for

It is meant to be used at home, but also in nurseries and by professionals who work with babies every day. It works in Catalan and Spanish, and the code is open under the AGPL-3.0 licence: anyone can review it, improve it or adapt it to another sign language.