--- title: Array.shift optimizations in Firefox's JS Engine | daily.dev description: Array.shift in Firefox's JS Engine has been optimized to improve performance by moving the pointer of the array instead of moving items individually. This... canonical: https://daily.dev/posts/array-shift-optimizations-in-firefox-s-js-engine-i8i8uhf7x twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Array.shift optimizations in Firefox's JS Engine | daily.dev og:description: Array.shift in Firefox's JS Engine has been optimized to improve performance by moving the pointer of the array instead of moving items individually. This... og:url: https://daily.dev/posts/array-shift-optimizations-in-firefox-s-js-engine-i8i8uhf7x og:image: https://api.daily.dev/og/posts/i8i8Uhf7X.png og:image:alt: Array.shift optimizations in Firefox's JS Engine 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. # Array.shift optimizations in Firefox's JS Engine **[Hacker News](https://daily.dev/sources/hn)** · 3 min read · 6 upvotes · 1 comments ## Summary Array.shift in Firefox's JS Engine has been optimized to improve performance by moving the pointer of the array instead of moving items individually. This results in a constant time complexity for shifting elements in the array. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Community discussion Top comments from developers on daily.dev. **@benredliber** · 0 upvotes > “Chrome has a similar algorithm, but it only works for arrays under size of ~50k items (A story for another day).” > > One hell of an interesting cliffhanger. Reading up more on this. --- Tags: [#javascript](https://daily.dev/tags/javascript), [#performance](https://daily.dev/tags/performance), [#firefox](https://daily.dev/tags/firefox) [View this post on daily.dev](https://daily.dev/posts/array-shift-optimizations-in-firefox-s-js-engine-i8i8uhf7x) ```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":"Array.shift optimizations in Firefox's JS Engine","url":"https://daily.dev/posts/array-shift-optimizations-in-firefox-s-js-engine-i8i8uhf7x","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/array-shift-optimizations-in-firefox-s-js-engine-i8i8uhf7x"},"datePublished":"2024-05-07T10:23:09.507Z","dateModified":"2024-05-09T08:29:02.242Z","description":"Array.shift in Firefox's JS Engine has been optimized to improve performance by moving the pointer of the array instead of moving items individually. 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