I built an Astro theme with a perfect 100/100 Lighthouse score and Enterprise SEO (Open Source)

When building a website for a B2B SaaS or a startup, everyone tells you that SEO and performance are crucial. Yet, when you look for a starter template, most of them look beautiful but fail miserably under the hood: no proper structured data, duplicate content issues, heavily bloated JavaScript, and terrible Lighthouse scores. I got tired of wrestling with Core Web Vitals and fixing missing hreflang tags on every new project. So, I decided to build the ultimate solution from scratch. Today, I’m open-sourcing Astro SEO Theme. It is a premium, 100% free, and open-source website template engineered specifically to dominate search engine rankings and generative AI engines (GEO). / astro-seo-theme Astro SEO Theme The ultimate open-source SEO theme for Astro, designed for B2B SaaS and Enterprise. View Demo · Report Bug · Request Feature Astro SEO Theme is an open-source website template built with Astro, Tailwind CSS v4, and React. You get a highly-optimized landing page, dynamic blog, case studies section, and enterprise-grade SEO tooling in one repo. It's designed so you can launch a premium web presence for a B2B SaaS or startup just by editing content, instead of wrestling with Core Web Vitals from scratch. Unlike generic themes, it ships with an incredibly strict SEO setup, multilingual i18n, security headers, and CI pipelines already wired up. Live demo: astro-seo-theme.vercel.app Validated perfectly for Mobile & Desktop Performance, Accessibility, Best Practices, and SEO. Three content hubs in one. High-converting landing page, markdown-driven blog, and case studies portfolio, all sharing a single responsive layout and megamenu. Enterprise-grade SEO.… View on GitHub Astro is already incredibly fast, but speed is only half the battle. To rank well in 2026, you need proper metadata, schema markup for Rich Snippets (AEO), and localized routes to avoid duplicate content penalties. I built Astro SEO Theme to solve all of this out of the box. You get three content hubs (a high-converting Landing Page, a Markdown-driven Blog, and a Case Studies portfolio), all sharing a unified architecture. Here is what makes this theme different from generic templates: Zero-JS by Default (100/100 Lighthouse): Built using Astro Islands. We ship exactly 0 KB of client-side JavaScript unless it's strictly necessary (like for the React-based dark mode toggle). Enterprise-Grade SEO: It automatically generates centralized hreflang tags, dynamic JSON-LD structured data (for Articles, Breadcrumbs, and FAQSchemas), auto-generated sitemaps, and canonical URLs. Multilingual Ready (i18n): File-based routing makes it trivial to scale globally. It currently ships with complete English and Spanish implementations. Author E-E-A-T Support: Dedicated JSON collections for authors to establish expertise and trust with Google's search algorithms. Modern Stack: Powered by the latest and greatest: Astro, Tailwind CSS v4, and React. Production Hardened: Includes a strict Content Security Policy (CSP) and security headers configured for Vercel deployments. You don't need to clone the repo manually. You can scaffold a new project directly using the Astro CLI in seconds: npm create astro@latest -- --template druedaro/astro-seo-theme my-saas-website cd my-saas-website npm install npm run dev If you want to see it in action first, check out the Live Demo. I built this to save developers and founders dozens of hours of technical SEO configuration. I would love to hear your thoughts, feedback, or feature requests. If you find it useful for your next project, dropping a ⭐ on GitHub would mean the world to me! Happy building! 🚀