--- title: Introducing the JetStream 3 Benchmark Suite | daily.dev description: JetStream 3.0 is a new cross-browser benchmark suite developed collaboratively by Apple, Google, and Mozilla. It overhauls how WebAssembly and JavaScript... canonical: https://daily.dev/posts/introducing-the-jetstream-3-benchmark-suite-15mtu1ee9 twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Introducing the JetStream 3 Benchmark Suite | daily.dev og:description: JetStream 3.0 is a new cross-browser benchmark suite developed collaboratively by Apple, Google, and Mozilla. It overhauls how WebAssembly and JavaScript... og:url: https://daily.dev/posts/introducing-the-jetstream-3-benchmark-suite-15mtu1ee9 og:image: https://api.daily.dev/og/posts/15Mtu1EE9.png og:image:alt: Introducing the JetStream 3 Benchmark Suite 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. # Introducing the JetStream 3 Benchmark Suite **[WebKit](https://daily.dev/sources/webkit)** · 25 min read · 0 upvotes · 0 comments ## Summary JetStream 3.0 is a new cross-browser benchmark suite developed collaboratively by Apple, Google, and Mozilla. It overhauls how WebAssembly and JavaScript performance is measured by replacing isolated startup/runtime phases with full lifecycle scoring (first iteration, worst case, average case), and shifting from microbenchmarks to larger real-world workloads. The WebKit team used JetStream 3 as a driver for major JavaScriptCore improvements: WasmGC allocation inlining (eliminating two-allocation patterns for ~40% gains), GC type reference counting overhaul, Cohen's type display algorithm for fast type checks, a new greedy register allocator with B+ tree interval tracking (~2x faster for large functions), polymorphic indirect call inlining, BigInt arithmetic improvements (Comba multiplication, DIV2BY1 division), and a full rewrite of the microtask queue and Promise combinators from JS builtins to C++. These changes collectively delivered roughly a 10% performance improvement from Safari 26.0 to 26.4. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [WebKit Features for Safari 26.6](https://daily.dev/posts/webkit-features-for-safari-26-6-5iedohctc) · WebKit · 6 upvotes · 1 comments - [WebAssembly vs. JavaScript: Testing Side-by-Side Performance](https://daily.dev/posts/webassembly-vs-javascript-testing-side-by-side-performance-uai1ulk0u) · The New Stack · 0 upvotes · 0 comments - [The 7 Walls JavaScript Hits — and How WebAssembly Gets Past Them](https://daily.dev/posts/the-7-walls-javascript-hits-and-how-webassembly-gets-past-them-isxmm7isd) · DEV · 2 upvotes · 0 comments --- Tags: [#javascript](https://daily.dev/tags/javascript), [#webassembly](https://daily.dev/tags/webassembly), [#safari](https://daily.dev/tags/safari) [View this post on daily.dev](https://daily.dev/posts/introducing-the-jetstream-3-benchmark-suite-15mtu1ee9) ```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":"TechArticle","headline":"Introducing the JetStream 3 Benchmark Suite","url":"https://daily.dev/posts/introducing-the-jetstream-3-benchmark-suite-15mtu1ee9","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/introducing-the-jetstream-3-benchmark-suite-15mtu1ee9"},"datePublished":"2026-03-31T18:31:13.647Z","dateModified":"2026-03-31T19:23:56.345Z","description":"JetStream 3.0 is a new cross-browser benchmark suite developed collaboratively by Apple, Google, and Mozilla. It overhauls how WebAssembly and JavaScript...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/a37defe594ee04b60773788411515114?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/a37defe594ee04b60773788411515114?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"WebKit","inLanguage":"en","publisher":{"@type":"Organization","name":"daily.dev","url":"https://daily.dev","logo":{"@type":"ImageObject","url":"https://daily.dev/apple-touch-icon.png","width":180,"height":180}},"author":{"@type":"Organization","name":"WebKit","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/webkit","url":"https://daily.dev/sources/webkit"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/introducing-the-jetstream-3-benchmark-suite-15mtu1ee9","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"javascript,webassembly,safari","timeRequired":"PT25M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"WebKit","item":"https://daily.dev/sources/webkit"},{"@type":"ListItem","position":3,"name":"Introducing the JetStream 3 Benchmark Suite"}]} ```