--- title: The Case of the Rapidly Disappearing Disk Space --... description: Coding agents can rapidly eat disk space through runaway file generation and sloppy cleanup. One agent generated large volumes of data that piled up in Time... canonical: https://daily.dev/posts/the-case-of-the-rapidly-disappearing-disk-space----fatbobman-s-swift-weekly-160-zfbs3w4ju twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: The Case of the Rapidly Disappearing Disk Space -- Fatbobman's Swift Weekly #160 | daily.dev og:description: Coding agents can rapidly eat disk space through runaway file generation and sloppy cleanup. One agent generated large volumes of data that piled up in Time... og:url: https://daily.dev/posts/the-case-of-the-rapidly-disappearing-disk-space----fatbobman-s-swift-weekly-160-zfbs3w4ju og:image: https://api.daily.dev/og/posts/zfBS3W4jU.png og:image:alt: The Case of the Rapidly Disappearing Disk Space -- Fatbobman's Swift Weekly #160 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. # The Case of the Rapidly Disappearing Disk Space -- Fatbobman's Swift Weekly #160 **[Fatbobman](https://daily.dev/sources/fatbobman)** · [@fatbobman](https://daily.dev/fatbobman) · 11 min read · 0 upvotes · 1 comments ## Summary Coding agents can rapidly eat disk space through runaway file generation and sloppy cleanup. One agent generated large volumes of data that piled up in Time Machine local snapshots. Another left a test script calling mkdtempSync without cleanup, unpacking a 5.7 GB repo into a new directory on every QA run. The newsletter also covers Swift Optional tricks, finding SwiftUI redraws in Xcode Instruments, iOS 27's new Now Playing framework, iPhone Duo fold-aware layouts, and szt, a Swift CLI that scanned 667,000 files (123 GB) in 2.4 seconds versus about 17 seconds for du. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Questions this post answers ### why is my disk space disappearing rapidly when using AI coding agents like Claude Code Coding agents can exhaust disk space in two common ways: generating large volumes of files that get retained by Time Machine local snapshots, and leaving behind temp directories from buggy cleanup code. One reported case involved a test script calling mkdtempSync without any cleanup, unpacking a 5.7 GB repository into a new directory on every QA run. Excluding agent working directories from backups and clearing local snapshots resolved the first issue. _Developers wrestling with agent-driven disk bloat compare fixes and tooling like this on daily.dev._ ### how fast is the szt command line tool compared to du for checking disk usage on macOS The szt (sizetree) Swift CLI scanned a directory with 667,000 files totaling 123 GB in 2.4 seconds, versus about 17 seconds for the traditional du command. It achieves this using macOS's getattrlistbulk to fetch file metadata in batches and by scanning directories in parallel across multiple threads, then displaying usage as a colorful tree prioritizing the largest directories. _Developers picking disk-analysis tools track fast alternatives to du like this on daily.dev._ ### how do I run multiple Claude Code agents safely on the same Xcode project without them interfering Git worktrees isolate source code between parallel agents but not build and runtime environments, so two agents can both report successful builds while sharing the same Simulator, causing one agent's app install to overwrite another's and corrupt test verification. The fix is isolating DerivedData directories, Simulators, and build configurations per agent, not just the source code. _Teams running parallel coding agents on Xcode projects track isolation patterns like this on daily.dev._ ## Community discussion Top comments from developers on daily.dev. **@nazmoonmunny** · 0 upvotes > Deleting files won't free space a local snapshot still holds, so `tmutil listlocalsnapshots /` is worth running first. Mine was empty, but my user temp folder still had 378 folders left by tool runs. ## Similar posts on daily.dev - [When the Mac mini’s Price Is No Longer Mini -- Fatbobman's Swift Weekly \#152](https://daily.dev/posts/when-the-mac-mini-s-price-is-no-longer-mini----fatbobman-s-swift-weekly-152-0rhl0oa2z) · Fatbobman · 0 upvotes · 0 comments - [du Said 120 GB. The Disk Said 0.. du reported 120 GB in…](https://daily.dev/posts/du-said-120-gb-the-disk-said-0-du-reported-120-gb-in--59hajxtsu) · Medium · 0 upvotes · 0 comments - [The Vanishing WWDC Wishlists -- Fatbobman's Swift Weekly \#136](https://daily.dev/posts/the-vanishing-wwdc-wishlists----fatbobman-s-swift-weekly-136-pspzuueso) · Fatbobman · 1 upvotes · 0 comments - [How to Clear 50\+ GB of “System Data” on macOS: The Developer’s Playbook](https://daily.dev/posts/how-to-clear-50-gb-of-system-data-on-macos-the-developer-s-playbook-bxpfw3mwm) · Medium · 0 upvotes · 0 comments --- Tags: [#ai-agents](https://daily.dev/tags/ai-agents), [#swift](https://daily.dev/tags/swift), [#claude-code](https://daily.dev/tags/claude-code), [#swiftui](https://daily.dev/tags/swiftui), [#xcode](https://daily.dev/tags/xcode) [View this post on daily.dev](https://daily.dev/posts/the-case-of-the-rapidly-disappearing-disk-space----fatbobman-s-swift-weekly-160-zfbs3w4ju) ```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":"The Case of the Rapidly Disappearing Disk Space -- Fatbobman's Swift Weekly #160","url":"https://daily.dev/posts/the-case-of-the-rapidly-disappearing-disk-space----fatbobman-s-swift-weekly-160-zfbs3w4ju","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/the-case-of-the-rapidly-disappearing-disk-space----fatbobman-s-swift-weekly-160-zfbs3w4ju"},"datePublished":"2026-11-02T10:07:43.231Z","dateModified":"2026-11-02T10:08:18.609Z","description":"Coding agents can rapidly eat disk space through runaway file generation and sloppy cleanup. 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