A pattern catalogue forVaadin Flow — small, focused recipes that solve real production problems. Each one is documented as a blog post with the runnable code and the trade-offs explained.

What’s covered (so far)

• File upload & download — streaming large files, progress UI, server-side validation
• REST integration — calling external APIs from inside Flow without blocking the UI thread
• Observer pattern in Flow — broadcasting events between sessions
• i18n — resource bundles, locale switching, RTL support
• Login flows — both standard and SSO/OIDC patterns
• Component extraction — when to compose, when to inherit, when to write a Web Component
• JSON export — turning UI state into a download artefact

Why this exists

Vaadin Flow is great when you know the patterns; it’s frustrating when you don’t. Most of the work I do for clients ends up in 2-3 reusable patterns per project. Rather than re-derive them every time, they live here as public-domain reference material.

All articles, runnable examples and discussion live in theVaadin category.