--- title: "Sitemap uses `new Date()` for `lastModified` (lint/sitemap-lastmod-now)" description: "lint/sitemap-lastmod-now: A lastmod that changes on every build tells crawlers every page changed every time." canonical: https://void-design.vercel.app/rules/lint/sitemap-lastmod-now lastModified: 2026-09-16 --- # Sitemap uses `new Date()` for `lastModified` `lint/sitemap-lastmod-now` · severity **warn** · category Lint · detected by `void lint` and `void audit` ## Why it matters A lastmod that changes on every build tells crawlers every page changed every time. Google learns to ignore the site's lastmod entirely, so real updates stop getting priority recrawls. ## How to fix it Use the content's real update date (frontmatter `updated`, CMS `updatedAt`, a hand-maintained date) — never build time. ## Example ```ts posts.map((p) => ({ url: `${site.url}/blog/${p.slug}`, lastModified: p.updated })) ``` ## References - https://developers.google.com/search/blog/2023/06/sitemaps-lastmod-ping ## More lint rules `void lint` reports 67 rules in this category. Static source checks with no browser: Tailwind v4 silent failures, Next.js 16 API traps, React render-body bugs, accessibility markup, SEO files and motion hygiene. - `missing-llms-txt` No `/llms.txt` — [lint/missing-llms-txt](https://void-design.vercel.app/rules/lint/missing-llms-txt) - `dynamic-metadata-streaming` Request-time `generateMetadata` without `htmlLimitedBots` — [lint/dynamic-metadata-streaming](https://void-design.vercel.app/rules/lint/dynamic-metadata-streaming) - `missing-lang` Root `` without `lang` — [lint/missing-lang](https://void-design.vercel.app/rules/lint/missing-lang) - `jsonld-missing` No JSON-LD structured data — [lint/jsonld-missing](https://void-design.vercel.app/rules/lint/jsonld-missing) - `multiple-h1` More than one `

` in a route's page + layouts — [lint/multiple-h1](https://void-design.vercel.app/rules/lint/multiple-h1) - `jsonld-deprecated-type` JSON-LD type that no longer produces rich results — [lint/jsonld-deprecated-type](https://void-design.vercel.app/rules/lint/jsonld-deprecated-type) - `route-js-budget` Route first-load JS over budget (from `.next` build output) — [lint/route-js-budget](https://void-design.vercel.app/rules/lint/route-js-budget) - `animate-undefined` `animate-*` class with no matching `--animate-*` theme variable or `@keyframes` — [lint/animate-undefined](https://void-design.vercel.app/rules/lint/animate-undefined) Detected by `void lint` and `void audit`. Explain it in a terminal: `void rules lint/sitemap-lastmod-now`