• Breaking: removes data deep merge opt-out. eleventyConfig.setDataDeepMerge(false) now throws an error #3937 Relevant docs: https://www.11ty.dev/docs/data-deep-merge/
• Breaking: change jsTruthy: true in default liquidjs options #3507
• Breaking: change Liquid default parameter parsing to builtin instead of legacy #2679 Escape hatch to disable here: https://www.11ty.dev/docs/languages/liquid/#shortcode-parameter-parsing
• Using npm Trusted Publishers
• Minor build performance improvement in TemplateMap #3939
• Fixes issue with Markdown triple-backtick code blocks in a markdown template used in a Markdown layout #3954
• Setting markdownTemplateEngine: "md" shows a debug warning (and is aliased to false) #3925
• Fix paired shortcodes in Nunjucks macros #2261
• Improved error messaging for dynamicPermalink: false and non-string permalink values #838
• Fixes: files ignored via the preprocessor API were still populating collections keys (though the collection would be empty) #3933
• Fixes bug with Configuration API for ignores were not respected when using absolute paths for input directory #3896
• Fixes bug with single character directory names when using filePathStem #3932
• Fixes canary-only bug with Computed Data callbacks that assign variables #3917
• Feature: memoize date: git Last Modified and date: git Created options, adds JavaScript exports for these utilities to use them in your own JavaScript #3959
• Fix bug with ESM dependencies hot reloading #3899
• Move away from git:// protocol in package.json repository->url #4151
• page, eleventy, and collections are now accessible inside of Liquid {% render %} tags #1541

Dependencies

• Major dependency bump @sindresorhus/slugify from v2 to v3 (not breaking, already at Node 20+ minimum) #3942
• Major dependency bump chokidar from v4 to v5 (Breaking: Node 20.19+ minimum) #4185
• Bump liquidjs to 10.24 #3957 #3961
• Bump tinyglobby to 0.2.15 #3934
• Progress on reducing entities duplication #4154

Milestone: https://github.com/11ty/eleventy/milestone/46?closed=1
Full Changelog: v4.0.0-alpha.4...v4.0.0-alpha.5