--- title: Wallaby.js is a test runner which runs your JavaScript... description: Wallaby.js is a JavaScript and TypeScript test runner that executes tests in real time as you type, displaying results inline in your editor. Key features... canonical: https://daily.dev/posts/wallaby-js-is-a-test-runner-which-runs-your-javascript-and-typescript-tests-as-you-type-streaming-r-qrofscpgu twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Wallaby.js is a test runner which runs your JavaScript and TypeScript tests as you type, streaming results next to your code. It also feeds rich runtime context to AI tools to help you write and fix code faster. | daily.dev og:description: Wallaby.js is a JavaScript and TypeScript test runner that executes tests in real time as you type, displaying results inline in your editor. Key features... og:url: https://daily.dev/posts/wallaby-js-is-a-test-runner-which-runs-your-javascript-and-typescript-tests-as-you-type-streaming-r-qrofscpgu og:image: https://api.daily.dev/og/posts/QRoFSCPgU.png og:image:alt: Wallaby.js is a test runner which runs your JavaScript and TypeScript tests as you type, streaming results next to your code. It also feeds rich runtime context to AI tools to help you write and fix code faster. og:image:width: 1200 og:image:height: 630 og:locale: en --- > ## Documentation Index > Fetch the complete documentation index at: https://daily.dev/llms.txt > Use this file to discover all available pages before exploring further. # Wallaby.js is a test runner which runs your JavaScript and TypeScript tests as you type, streaming results next to your code. It also feeds rich runtime context to AI tools to help you write and fix code faster. **[Alexey Zerkalenkov](https://daily.dev/sources/tzhsbevyajhcmr0fmoxfj)** · [@alexeyzerkalenkov](https://daily.dev/alexeyzerkalenkov) · 0 upvotes · 0 comments ## Summary Wallaby.js is a JavaScript and TypeScript test runner that executes tests in real time as you type, displaying results inline in your editor. Key features include time travel debugging, live runtime values, inline code coverage, selective test execution, and performance profiling. A new MCP server integration gives AI coding assistants (Copilot, Cursor, Claude Code, Windsurf, Cline) live access to test results, runtime values, execution paths, and dependency graphs for more accurate debugging and code generation. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Cloud MCP: Give Your AI Assistant Access to Your Test Runs](https://daily.dev/posts/cloud-mcp-give-your-ai-assistant-access-to-your-test-runs-ariwbbaqw) · cypress · 2 upvotes · 0 comments - [Next.js DevTools MCP: Your Development Server Just Got Sm...](https://daily.dev/posts/next-js-devtools-mcp-your-development-server-just-got-sm--ipezwr1nf) · Trevor Lasn · 3 upvotes · 0 comments --- Tags: [#javascript](https://daily.dev/tags/javascript), [#testing](https://daily.dev/tags/testing), [#typescript](https://daily.dev/tags/typescript), [#mcp](https://daily.dev/tags/mcp) [View this post on daily.dev](https://daily.dev/posts/wallaby-js-is-a-test-runner-which-runs-your-javascript-and-typescript-tests-as-you-type-streaming-r-qrofscpgu) ```json {"@context":"https://schema.org","@graph":[{"@type":"Organization","@id":"https://daily.dev/#organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180},"sameAs":["https://twitter.com/dailydotdev","https://github.com/dailydotdev","https://www.linkedin.com/company/daily-dev-ltd"]},{"@type":"WebSite","@id":"https://daily.dev/#website","url":"https://daily.dev","name":"daily.dev","publisher":{"@id":"https://daily.dev/#organization"},"potentialAction":{"@type":"SearchAction","target":{"@type":"EntryPoint","urlTemplate":"https://daily.dev/search?q={search_term_string}"},"query-input":"required name=search_term_string"}}]} {"@context":"https://schema.org","@type":"DiscussionForumPosting","mainEntityOfPage":"https://daily.dev/posts/wallaby-js-is-a-test-runner-which-runs-your-javascript-and-typescript-tests-as-you-type-streaming-r-qrofscpgu","headline":"Wallaby.js is a test runner which runs your JavaScript and TypeScript tests as you type, streaming results next to your code. 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