What's new in Astro 7? From 7.0 to 7.3, explained and measured

Astro 7 launched on 22 June 2026 with one theme: speed, above all when building your site. Three minor releases have followed since. Astro 7.1 brought more control, 7.2 experimental incremental builds and 7.3 multiple preview servers. The latest version is 7.3.5, from 24 September 2026. AstroBuild itself runs on Astro and, for this article, was built with 7.2.9, with 7.3.5 and with incremental builds; the results are further down.

What does Astro 7 change about building your site?

Astro 7 mainly makes building faster. The old Go compiler was replaced by a compiler written in Rust, Vite 8 bundles with Rolldown, Sätteri processes the Markdown and a new rendering engine generates pages through a queue. According to Astro, the biggest gain comes from native code in Rust; together with the faster rendering, builds are 15 to 61% faster. The minor releases since then add control and experimental features.

Where does the speed gain in Astro 7 come from?

Astro focuses on bundling the site. The release announcement puts it like this: “The biggest gains come from moving some of the slowest parts of the build into native code written in Rust.” The compiler, the bundler, the Markdown processing and the rendering all changed.

A compiler in Rust

The new compiler for .astro files is a full rewrite in Rust, which Astro describes as mostly backwards compatible. The previous Go compiler was removed from Astro 7, together with the experimental.rustCompiler flag. On its own the compiler does not gain much: Astro measures roughly 6% faster builds on docs.astro.build from the compiler alone. Compiling .astro files is rarely the bottleneck.

Vite 8 and the Rolldown bundler

Astro 7 runs on Vite 8, which bundles with Rolldown. According to Astro, Markdown processing and bundling, the merging and optimising of code and content, typically take up most of the build time. That is where Astro 7 put its focus.

Sätteri processes the Markdown

As of Astro 7, Sätteri is the default for turning Markdown into HTML. In Astro 6.4 it was still an opt-in. According to Astro, it shaved over a minute off the builds of the Astro docs and the Cloudflare docs. The downside: remark and rehype plugins no longer work without the extra package @astrojs/markdown-remark. Erika, a member of the Astro core team and the creator of Sätteri, explained the choice like this:

The vast majority of our users don’t use any sort of unified plugins, so a pipeline that’s faster (and about 100 deps leaner) felt like a better default. Erika, Astro core team

AstroBuild ran into this itself in September 2026. A rehype plugin for a block halfway through every blog post required that extra package, which would have moved all Markdown processing back to the old pipeline. AstroBuild chose a different solution and stayed with Sätteri.

Faster rendering

Generating the pages themselves changed too. Astro replaced the rendering engine with “a faster queue-based approach”, which queues the sections of a page more efficiently. That approach had been available as an experimental option since Astro 6.0 and is now the default. The gain depends on the page: mostly pages with many dynamic expressions benefit, while plain static pages gain little.

How much faster are builds really?

Astro reports builds that are 15 to 61% faster. That comes from Astro’s own benchmark, run on a MacBook Pro with an Apple M4 Pro and 48 GB of memory, measuring before and after Astro 7. The six test sites show how much the gain varies:

Test site	Pages	Before	After	Gain
astro.build	about 308	62.70 s	24.24 s	61%
docs.astro.build	about 6,313	114.54 s	73.53 s	36%
tauri.app	7,117	86.12 s	55.33 s	36%
developers.cloudflare.com	8,431	386.89 s	261.94 s	32%
biomejs.dev	about 6,488	176.39 s	149.90 s	15%
aspire.dev	13,275	385.84 s	326.11 s	15%

Source: the Astro 7 release announcement. The gain percentages were calculated by AstroBuild from the published times.

In percentage terms, the smallest test site gained the most: astro.build built more than twice as fast. In seconds, developers.cloudflare.com gained the most, over two minutes. According to Astro, the gain depends mainly on how much of your build goes to .astro compilation and Markdown. Matthew Phillips, a member of the Astro core team, replied on Hacker News to someone who saw no faster builds after upgrading:

How many pages is it? The performance improvements are mostly for larger sites (thousands of pages) and especially when using a lot of MDX. Matthew Phillips, Astro core team

The exact gain for your own site therefore depends on your content, your integrations and your build machine. Measure it yourself, before and after.

What is new since Astro 7.0?

Since Astro 7.0, three minor releases have appeared, with no breaking changes according to Astro. Astro 7.1 gives more control over CSP and pagination among other things, 7.2 brings experimental incremental builds, and 7.3 lets you run multiple preview servers side by side. The latest patch is 7.3.5 from 24 September 2026. If you are on Astro 7, you can upgrade without changing code.

Version	Released	Main additions	Status
Astro 7.1	16 July 2026	CSP directives per element or attribute, format for paginate(), multiple dev servers, deferRender	Stable, chunked content storage experimental
Astro 7.2	6 August 2026	Incremental static builds, session: false, astro preview --background	Incremental builds experimental
Astro 7.3	3 September 2026	Multiple preview servers, loggers for image services and cache providers	Stable

Astro 7.1: more control

Astro 7.1 launched on 16 July 2026 and is about finer settings. Daniel Curtis summed it up for InfoQ:

Astro 7.1, out on 16 July, is about control rather than speed. Daniel Curtis, InfoQ

Astro’s Content Security Policy now supports the directives script-src-elem, script-src-attr, style-src-elem and style-src-attr, through the kind option in security.csp. That lets a site allow inline style attributes, for example, without also allowing inline <style> blocks. A CSP is also on the security checklist in the article why a static site is safer than a WordPress site. Astro 7.1 also gave paginate() a format function for hosts without URL rewrites, astro dev --ignore-lock can start a second dev server, and deferRender lets large content collections build with less memory. Splitting content storage into chunks is still experimental.

Astro 7.2: incremental builds, still experimental

Astro 7.2 launched on 6 August 2026. The big addition is incremental static builds: Astro reuses pages from the previous build when nothing about them changed. You turn them on with experimental: { incrementalBuild: true } and give each page in getStaticPaths() a cacheKey. The new digest field on a collection entry is handy for that. Matthew Phillips wrote in the release post:

This is an early, experimental feature and we want to hear how it holds up on real sites. Matthew Phillips, Astro core team

Astro itself publishes no figure for the gain. Rishi Raj Jain of LaunchFast measured a drop from about 16.5 to about 10 seconds on a 661-page site. After one edited post, 637 of the 661 pages came from the cache. Mind the limitations: a change to the middleware does not invalidate the cache, and a change to the config or the dependencies invalidates it completely. In CI, the cache in node_modules/.astro/ has to be preserved between runs.

Astro 7.2 also brought session: false to turn sessions off, useful on serverless and edge hosting. AstroBuild uses that option itself. And astro preview can now run in the background.

Astro 7.3: preview servers and Cloudflare

Astro 7.3 launched on 3 September 2026. With astro preview --ignore-lock, multiple preview servers run side by side, handy for end-to-end tests with Playwright. Authors of custom image services and cache providers get a logger. At the same time, the Cloudflare adapter gained a finalize() helper in version 14.3.0 for anyone writing their own worker entrypoint. And since 7.3.0, incremental builds also work with build.concurrency above 1. The docs still list that as a limitation, but according to the changelog it has been lifted.

What does Astro 7.3 deliver for a small site like AstroBuild?

On AstroBuild, the upgrade to 7.3.5 gave no measurable build gain. With incremental builds, 26 of the 27 blog pages came from the cache, which cut page generation by 0.4 seconds. AstroBuild has 45 statically built pages, including 27 blog pages: nine posts in three languages. With so few pages, skipping pages saves little time.

AstroBuild shows what Astro on Cloudflare does in practice, for developers and decision-makers in the Benelux. That is why the site measures upgrades on itself, with this result:

Situation	Build time	From the cache
Astro 7.2.9 with @astrojs/cloudflare 14.2.5	4.90 s	not applicable
Astro 7.3.5 with @astrojs/cloudflare 14.3.3	4.84 s	not applicable
Astro 7.3.5, incremental, no change (one run)	4.81 s	27 of 27 blog pages
Astro 7.3.5, incremental, after one edited post	4.58 s	26 of 27 blog pages

Measured on 27 September 2026 with astro build, without Pagefind and the site’s own build scripts. For each situation the median of three runs after a warm-up build, unless stated otherwise, on an AMD Ryzen 9 9950X3D with 64 GB of memory on Windows 11 and Node 24.19.0. The differences in total build time are small: the full builds on 7.3.5 already ranged from 4.83 to 5.39 seconds, and the incremental run without changes (4.81 s) was not measurably faster than a full build. The clear difference is in the phase that generates the static pages, which went from 1.35 to 0.96 seconds with the incremental build. Rendering a single page takes tens of milliseconds here.

One lesson came unexpectedly. Setting only astro to 7.3.5 and leaving the Cloudflare adapter on 14.2.5 made the build fail with MISSING_EXPORT "beginContentEntryCollection". That adapter lists astro ^7.2.0 as compatible, so npm simply allowed the combination. With the adapter on 14.3.3, the same code built without changes. As of 27 September 2026, AstroBuild runs in production on Astro 7.3.5 with that adapter.

Is runtime speed still the strong point?

Yes. Keep build time (how fast your site gets built) separate from runtime speed (how fast it loads for visitors). Astro 7 and its minors mainly improve build time. Runtime speed, static HTML with little JavaScript, was already Astro’s core strength and still is. Why that matters for your visibility is covered in Core Web Vitals and SEO.

How do you upgrade to Astro 7.3?

Upgrade astro and the official integrations together. The docs recommend npx @astrojs/upgrade, which does exactly that. On minor releases, the docs say: “Minor releases primarily introduce new features and improvements that you may wish to try, but require no changes to your code.” The measurement above shows why the adapter has to be upgraded too. Also:

• Test the upgrade in a separate branch first.
• Still on Astro 6? Follow the upgrade guide to v7 first. If you use remark or rehype plugins, install @astrojs/markdown-remark.
• Watch for behaviour changes in patches: since 7.1.2 cookie values are no longer needlessly percent-encoded, since 7.3.2 <script>{value}</script> is escaped in MDX, and since 7.2.5 deprecation messages point to Astro 8.
• If you use incremental builds, use the latest patch. Several fixes landed between 7.2.5 and 7.3.4, including for stale CSS.

What does it mean that the Astro team works at Cloudflare?

Not much changes for users. In January 2026, The Astro Technology Company, the company behind Astro, joined Cloudflare. According to the team, the framework stays free, open source and MIT-licensed, with the same open governance and roadmap, and supports a wide set of hosting platforms, not just Cloudflare. The tie to an edge platform does fit what Astro is good at: fast sites close to the visitor.

Is Astro 7 worth the upgrade?

Yes, especially if you wait a long time for builds. Astro 7 brought a Rust compiler, Vite 8 with Rolldown, Sätteri and faster rendering; the minors 7.1 to 7.3 added control and experimental incremental builds. According to Astro, the gain is largest where .astro compilation and Markdown make up a big share of the build. Incremental builds only pay off with many pages. Upgrade the adapter along with it.

You can follow new versions on the AstroBuild release calendar, straight from GitHub. New to Astro? Start with what Astro is and why it feels fast.