Explore our collection of posts, filled with helpful tips and exciting ideas. Our team writes about topics that matter to anyone with an interest in keeping user interfaces in good condition. Whether you're learning new skills or just looking for fresh insights, you'll find plenty of great reads here.
When a major social media platform's in-house Android snapshot testing hit scaling limits with hundreds of developers, Happo built a Gradle plugin bridge. It preserved their existing Roborazzi setup while offloading storage, diffing, and reporting — showing that build vs. buy isn't always binary.
Screenshot testing is well-established on the web, but mobile developers often face different challenges: bloated repositories, slow builds, and scaling pain from storing PNGs directly in the repo. This interview with Henric explores how Happo solved these problems for one large social media platform.
In this interview, Happo co-founder Henric explains how <A11y/> makes accessibility testing continuous rather than one-time. The tool integrates with Storybook, Playwright, and Cypress to surface WCAG violations on every pull request — Happo’s own product started with over 1,400 violations before using it.
Joe Lencioni helped bring accessibility into the mainstream at Airbnb in 2016, co-shaping eslint-plugin-jsx-a11y into a tool downloaded over 16 million times weekly. His latest work, <A11y/> by Happo, makes continuous accessibility testing as natural as visual regression testing.
The European Accessibility Act requires all EU digital services to meet accessibility standards by June 2025. Happo's continuous accessibility regression testing detects violations on every pull request, helping teams stay compliant without audits — catching what breaks before it ships.
In 2016, Happo got its name from an unexpected source: a drawing by Henric's 3-year-old nephew labeled "Happo Carappo." Joe suggested keeping just "Happo," and the name was agreed on in a single GitHub comment — no branding agency required.
Screenshot testing is quietly used by teams at Airbnb, Patreon, Monzo, and Grammarly to keep UIs consistent and catch regressions before they ship. This article explores what makes screenshot testing one of frontend development’s most impactful — and most underrated — practices.
For teams that need complete data control, regulatory compliance, or maximum security, Happo offers an on-premise deployment: a full bundle including workers, web server, comparison engine, and database, installed within your own infrastructure with a three-month trial period.
Happo's new Support Contact Form makes getting help straightforward: pre-filled with your name and email, drag-and-drop file attachments, a Markdown-enabled message area, and automatic email confirmation — all accessible from a single click.
Happo now supports Single Sign-On via SAML, compatible with Auth0/Okta and Google Workspace. Your team can access Happo using existing company credentials — one login for all your tools, with enterprise-grade security backed by a standard identity protocol.
Spurious diffs — screenshots that render slightly differently between runs — waste time and slow down teams. Happo's Single Screenshot Retry lets you regenerate a specific screenshot without rerunning the full suite, pinpointing flaky components without disrupting the rest of your workflow.
Adding dark mode to happo.io started with replacing hard-coded CSS colors with variables — a step that turned out to be 90% of the work. This article walks through the full process: consolidating colors, iterating with screenshot testing, and shipping a user-controlled theme switcher.
Combining Storybook and Happo gives teams automated visual regression testing across browsers and devices. This guide covers setup, CI/CD integration, and the key benefits: consistent UI components, early detection of visual regressions, and less time spent on manual cross-browser testing.
Happo is a straight up life-saver. How many times did you think your change was contained only to discover that ten other teams started using what you built, and your change breaks three of the ten? Without Happo, you might not know.
Happo gives us the confidence that we are not introducing any unwanted visual changes in our pull requests. Something that pure end-to-end tests cannot always cover.
Happo supports the latest versions of most browsers and emulators. Their speed of image comparison is impressive. They also have GitHub and CI integration and plugins to support Storybook and Cypress directly.