--- title: Changelog: macOS Tahoe, lazy trees, and docs in... description: Determinate Nix 3.6.6 has been released, based on upstream Nix 2.29.0. Key highlights include confirmed compatibility with macOS Tahoe beta, performance and... canonical: https://daily.dev/posts/changelog-macos-tahoe-lazy-trees-and-docs-in-determinate-nix-3-6-6-qxruo4ifk twitter:card: summary_large_image twitter:site: @dailydotdev og:type: website og:site_name: daily.dev og:title: Changelog: macOS Tahoe, lazy trees, and docs in Determinate Nix 3.6.6 | daily.dev og:description: Determinate Nix 3.6.6 has been released, based on upstream Nix 2.29.0. Key highlights include confirmed compatibility with macOS Tahoe beta, performance and... og:url: https://daily.dev/posts/changelog-macos-tahoe-lazy-trees-and-docs-in-determinate-nix-3-6-6-qxruo4ifk og:image: https://api.daily.dev/og/posts/QXRUO4ifk.png og:image:alt: Changelog: macOS Tahoe, lazy trees, and docs in Determinate Nix 3.6.6 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. # Changelog: macOS Tahoe, lazy trees, and docs in Determinate Nix 3.6.6 **[Determinate Systems](https://daily.dev/sources/determinate-systems)** · 4 min read · 0 upvotes · 0 comments ## Summary Determinate Nix 3.6.6 has been released, based on upstream Nix 2.29.0. Key highlights include confirmed compatibility with macOS Tahoe beta, performance and reliability improvements to lazy trees (which have delivered 5x CI speedups for some users), and improved input caching that cuts CI times from over two minutes to under 20 seconds. The release also fixes a NixOS-specific bug in `determinate-nixd status` netrc-file checking, adds a sensible error message for misconfigured sandbox paths, and improves macOS upgrade support for systems using `nix profile`. ## Full article daily.dev links to this article rather than hosting it. Read it at the original source: ## Similar posts on daily.dev - [Changelog: Determinate Nix 3.21.7](https://daily.dev/posts/changelog-determinate-nix-3-21-7-spb0ixqhl) · Determinate Systems · 0 upvotes · 0 comments - [Changelog: a new upstream base, GC roots for nix eval, and a faster nix copy](https://daily.dev/posts/changelog-a-new-upstream-base-gc-roots-for-nix-eval-and-a-faster-nix-copy-a9ytihpvx) · Determinate Systems · 0 upvotes · 0 comments - [macOS Tahoe 26.2 Release Notes](https://daily.dev/posts/macos-tahoe-26-2-release-notes-r0coe82sh) · Hacker News · 0 upvotes · 0 comments - [Changelog: FlakeHub Cache edge routing and a few crash fixes](https://daily.dev/posts/changelog-flakehub-cache-edge-routing-and-a-few-crash-fixes-umodwxeoj) · Determinate Systems · 0 upvotes · 0 comments - [Changelog: faster evaluation and FedRAMP cache keys](https://daily.dev/posts/changelog-faster-evaluation-and-fedramp-cache-keys-qbkpwjrox) · Determinate Systems · 0 upvotes · 0 comments --- Tags: [#nixos](https://daily.dev/tags/nixos) [View this post on daily.dev](https://daily.dev/posts/changelog-macos-tahoe-lazy-trees-and-docs-in-determinate-nix-3-6-6-qxruo4ifk) ```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":"Changelog: macOS Tahoe, lazy trees, and docs in Determinate Nix 3.6.6","url":"https://daily.dev/posts/changelog-macos-tahoe-lazy-trees-and-docs-in-determinate-nix-3-6-6-qxruo4ifk","mainEntityOfPage":{"@type":"WebPage","@id":"https://daily.dev/posts/changelog-macos-tahoe-lazy-trees-and-docs-in-determinate-nix-3-6-6-qxruo4ifk"},"datePublished":"2026-07-26T07:48:49.821Z","dateModified":"2026-07-26T07:51:32.500Z","description":"Determinate Nix 3.6.6 has been released, based on upstream Nix 2.29.0. 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