--- title: Who Actually Runs Elixir in Production, Fact-Checked description: A viral infographic ranking 15 companies by valuation and claimed Elixir usage gets a row-by-row fact check against primary sources: engineering blogs, live... canonical: https://daily.dev/posts/who-actually-runs-elixir-in-production-fact-checked-onwrdty9g twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Who Actually Runs Elixir in Production, Fact-Checked | daily.dev og:description: A viral infographic ranking 15 companies by valuation and claimed Elixir usage gets a row-by-row fact check against primary sources: engineering blogs, live... og:url: https://daily.dev/posts/who-actually-runs-elixir-in-production-fact-checked-onwrdty9g og:image: https://api.daily.dev/og/posts/onwRdTY9G.png og:image:alt: Who Actually Runs Elixir in Production, Fact-Checked 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. # Who Actually Runs Elixir in Production, Fact-Checked **[Awesome Elixir](https://daily.dev/sources/awelix)** · 13 min read · 0 upvotes · 0 comments ## Summary A viral infographic ranking 15 companies by valuation and claimed Elixir usage gets a row-by-row fact check against primary sources: engineering blogs, live job postings, GitHub commits, and funding filings. Nine rows hold up as current, three are aging (real but 2-5 years stale), one (Pinterest) is stale with evidence pointing to a Kafka/Flink/Iceberg replacement, and two (Spotify, Together AI) are unsupported. Four rows mislabel the system or entity: Whatnot's claim describes the wrong product (Live Service, not the Python marketplace backend), SumUp's describes the wrong language era (mostly Erlang, Elixir only in the Brazil bank unit since 2019), and RBC and Adobe attribute a division (RBC Capital Markets) or acquired subsidiary (Frame.io) to the parent brand. The author also publicly corrects an earlier post claiming Together AI runs Elixir, since the sourcing job posting is no longer verifiable. The best-supported rows (PepsiCo, Discord, Supabase, Remote, Whatnot, Adobe/Frame.io) cluster around real-time fanout, correctness-under-concurrency, and whole-backend rewrites. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### Does Spotify actually run its backend on Elixir? No, not for listener-facing systems. The only documented Elixir use at Spotify is one internal debugging tool for the artist advertising platform, built around 2021. The same source widely cited for the claim explicitly states that listener-facing backend services are done with Java, a point a Hacker News thread in 2024 called out directly. _Developers vetting stack claims before a hire or acquisition decision can track sourcing disputes like this on daily.dev._ ### Is Pinterest still using Elixir for its Guardian spam detection system? No, not verifiably anymore. Pinterest built Guardian, a real-time spam and rules engine, in Elixir starting in late 2017, but the newest public description of Guardian, dated 2025, describes a Kafka, Flink, Iceberg, and StarRocks architecture with no mention of Elixir. Pinterest's own Elixir open-source repos are also dormant, with elixometer unpushed since 2023 and elixir_thrift deleted. _Anyone evaluating whether a company's old tech-stack reputation still holds can follow architecture shifts like this on daily.dev._ ### What does Whatnot actually use Elixir for in production? Elixir powers Whatnot's Live Service, the system behind live auctions, live chat, and stream state, built on Phoenix Channels, PubSub, and Horde, not the marketplace backend, which runs on Python. A February 2026 engineering post documented the Live Service handling 583,000 concurrent viewers during a livestream event and named a specific Elixir failure mode under peak load: distributed Erlang proxy calls timing out. _Engineers researching real-world Elixir use cases at scale can find deep dives like this one on daily.dev._ ## Similar posts on daily.dev - [State of Elixir 2025](https://daily.dev/posts/state-of-elixir-2025-yfahy0moj) · ElixirStatus · 31 upvotes · 2 comments - [150,000 Lines of Vibe Coded Elixir: The Good, The Bad, and The Ugly](https://daily.dev/posts/150-000-lines-of-vibe-coded-elixir-the-good-the-bad-and-the-ugly-iczorzav0) · ElixirStatus · 22 upvotes · 0 comments - [The Ultimate Showdown: Rails 8 vs Phoenix LiveView](https://daily.dev/posts/the-ultimate-showdown-rails-8-vs-phoenix-liveview-hgdubeoas) · Ruby Flow · 1 upvotes · 0 comments --- Tags: [#elixir](https://daily.dev/tags/elixir) [View this post on daily.dev](https://daily.dev/posts/who-actually-runs-elixir-in-production-fact-checked-onwrdty9g) ```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":"Who Actually Runs Elixir in Production, Fact-Checked","url":"https://daily.dev/posts/who-actually-runs-elixir-in-production-fact-checked-onwrdty9g","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/who-actually-runs-elixir-in-production-fact-checked-onwrdty9g"},"datePublished":"2026-10-01T20:49:31.497Z","dateModified":"2026-10-01T20:50:30.375Z","description":"A viral infographic ranking 15 companies by valuation and claimed Elixir usage gets a row-by-row fact check against primary sources: engineering blogs, live...","image":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/f1a1fbbb21f266283a17aaa829f5223d?_a=AQAEuop","thumbnailUrl":"https://media.daily.dev/image/upload/f_auto,q_auto/v1/posts/f1a1fbbb21f266283a17aaa829f5223d?_a=AQAEuop","isAccessibleForFree":true,"articleSection":"Awesome Elixir","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":"Awesome Elixir","logo":"https://media.daily.dev/image/upload/t_logo,f_auto/v1/logos/85a474f78b1b4d349119f7ce60d1438e","url":"https://daily.dev/sources/awelix"},"commentCount":0,"discussionUrl":"https://daily.dev/posts/who-actually-runs-elixir-in-production-fact-checked-onwrdty9g","interactionStatistic":[{"@type":"InteractionCounter","interactionType":{"@type":"LikeAction"},"userInteractionCount":0},{"@type":"InteractionCounter","interactionType":{"@type":"CommentAction"},"userInteractionCount":0}],"keywords":"elixir","timeRequired":"PT13M"} {"@context":"https://schema.org","@type":"BreadcrumbList","itemListElement":[{"@type":"ListItem","position":1,"name":"Home","item":"https://daily.dev"},{"@type":"ListItem","position":2,"name":"Awesome Elixir","item":"https://daily.dev/sources/awelix"},{"@type":"ListItem","position":3,"name":"Who Actually Runs Elixir in Production, Fact-Checked"}]} {"@context":"https://schema.org","@type":"FAQPage","@id":"https://daily.dev/posts/who-actually-runs-elixir-in-production-fact-checked-onwrdty9g#faq","mainEntity":[{"@type":"Question","name":"Does Spotify actually run its backend on Elixir?","acceptedAnswer":{"@type":"Answer","text":"No, not for listener-facing systems. The only documented Elixir use at Spotify is one internal debugging tool for the artist advertising platform, built around 2021. The same source widely cited for the claim explicitly states that listener-facing backend services are done with Java, a point a Hacker News thread in 2024 called out directly. Developers vetting stack claims before a hire or acquisition decision can track sourcing disputes like this on daily.dev."}},{"@type":"Question","name":"Is Pinterest still using Elixir for its Guardian spam detection system?","acceptedAnswer":{"@type":"Answer","text":"No, not verifiably anymore. Pinterest built Guardian, a real-time spam and rules engine, in Elixir starting in late 2017, but the newest public description of Guardian, dated 2025, describes a Kafka, Flink, Iceberg, and StarRocks architecture with no mention of Elixir. Pinterest's own Elixir open-source repos are also dormant, with elixometer unpushed since 2023 and elixir_thrift deleted. 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