--- title: SteamOS 3.6: How the Steam Deck atomic updates are improving description: Collabora details the engineering work done with Valve to improve SteamOS atomic system updates on the Steam Deck. The original tooling used RAUC and Casync... canonical: https://daily.dev/posts/steamos-3-6-how-the-steam-deck-atomic-updates-are-improving-pyiheplni twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: SteamOS 3.6: How the Steam Deck atomic updates are improving | daily.dev og:description: Collabora details the engineering work done with Valve to improve SteamOS atomic system updates on the Steam Deck. The original tooling used RAUC and Casync... og:url: https://daily.dev/posts/steamos-3-6-how-the-steam-deck-atomic-updates-are-improving-pyiheplni og:image: https://api.daily.dev/og/posts/pYihePlNi.png og:image:alt: SteamOS 3.6: How the Steam Deck atomic updates are improving 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. # SteamOS 3.6: How the Steam Deck atomic updates are improving **[Collabora Blog](https://daily.dev/sources/collabora)** · 5 min read · 0 upvotes · 0 comments ## Summary Collabora details the engineering work done with Valve to improve SteamOS atomic system updates on the Steam Deck. The original tooling used RAUC and Casync with an A/B partition scheme, but Casync had several limitations: single-threaded image hashing causing ~1 minute CPU spike before updates, no parallel HTTP downloads, and no resume capability on interrupted downloads. After evaluating options, the team switched to Desync, a Go-based Casync reimplementation with multi-threaded chunking and parallel HTTP support. The migration required non-trivial upstream contributions to Desync, including pre-calculated update plans, seed index validation, glob pattern support, and download size estimation. The result, shipped in SteamOS 3.6 Preview, delivers 30–50% faster update times, resumable downloads, more accurate progress reporting, and the ability to detect whether the current image has been modified. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### What improvements did SteamOS 3.6 make to system update speed on the Steam Deck? SteamOS 3.6 replaced Casync with Desync for applying atomic system updates, resulting in update times that are consistently 30–50% faster. Desync adds multi-threaded image chunking (eliminating the ~1-minute single-core CPU spike before updates), parallel HTTP downloads, resumable downloads on connection failure, and more accurate download progress reporting. _Engineers shipping embedded Linux update systems track tooling decisions like this on daily.dev._ ### Why did Valve and Collabora switch from Casync to Desync for SteamOS updates? Casync had several blockers: seed hashing was single-threaded and took nearly a full minute on the Steam Deck before any update could begin, parallel HTTP downloads required downstream patches, interrupted downloads restarted from scratch, and the project's last public release was in 2017 with stalled maintainer activity. Desync is an actively maintained Go reimplementation that addresses all these issues as a drop-in replacement. _Developers choosing between content-addressable sync tools for OS image delivery find comparisons like this on daily.dev._ ## Similar posts on daily.dev - [SteamOS 3.8 just dramatically improved a lot of handhelds except the Steam Deck itself](https://daily.dev/posts/steamos-3-8-just-dramatically-improved-a-lot-of-handhelds-except-the-steam-deck-itself-miqxly0cb) · XDA Developers · 1 upvotes · 0 comments - [A Linux Power User Puts SteamOS To Work](https://daily.dev/posts/a-linux-power-user-puts-steamos-to-work-vme39cquy) · Hackaday · 33 upvotes · 2 comments - [COSMIC Epoch 1.10 Released With Launcher Now Using GPU Accelerated Rendering](https://daily.dev/posts/cosmic-epoch-1-10-released-with-launcher-now-using-gpu-accelerated-rendering-jqlm2ljws) · Phoronix · 0 upvotes · 0 comments - [CachyOS rebuilds every package the 'wrong' way, and my Steam library runs faster for it](https://daily.dev/posts/cachyos-rebuilds-every-package-the-wrong-way-and-my-steam-library-runs-faster-for-it-axcg3joiz) · XDA Developers · 6 upvotes · 4 comments --- Tags: [#linux](https://daily.dev/tags/linux), [#steamos](https://daily.dev/tags/steamos) [View this post on daily.dev](https://daily.dev/posts/steamos-3-6-how-the-steam-deck-atomic-updates-are-improving-pyiheplni) ```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":"SteamOS 3.6: How the Steam Deck atomic updates are improving","url":"https://daily.dev/posts/steamos-3-6-how-the-steam-deck-atomic-updates-are-improving-pyiheplni","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/steamos-3-6-how-the-steam-deck-atomic-updates-are-improving-pyiheplni"},"datePublished":"2026-08-11T08:54:46.908Z","dateModified":"2026-08-11T09:22:42.635Z","description":"Collabora details the engineering work done with Valve to improve SteamOS atomic system updates on the Steam Deck. 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