# Show HN: Indexflow-SEO – A lightweight SEO analyzer written in Rust > Source: > Published: 2026-09-01 13:01:16+00:00 A blazing-fast, zero-dependency Technical SEO Quality Gate & GEO (Generative Engine Optimization) Auditor written in pure Rust. - 🛡️ **Technical SEO Gatekeeper**: Pre-flight validation for HTTP status codes, Canonical declaration equivalence,`noindex` /`nofollow` robots directives,`` tags, and`<h1>` headings. - 🤖 **GEO & AI Bot Auditing**: Audits crawler exclusion directives for`GPTBot` /`ChatGPT-User` ,`PerplexityBot` ,`ClaudeBot` /`anthropic-ai` , and`Google-Extended` — including per-bot`X-Robots-Tag` headers and`none` /`noai` . - 📑 **Schema.org Structured Data**: Extracts`application/ld+json` blocks, expands`@graph` and top-level arrays, and maps`@type` (string or array). - 🌐 **Social & Multilingual Metadata**: Parses OpenGraph, Twitter Card tags, and`link rel="alternate" hreflang` arrays. - ⚡ **Pure In-Memory Evaluation**: Char-boundary-safe HTML scanner (CJK / emoji never panic). Quote-aware tags, unquoted attributes, multiline meta, HTML comments and`<script>` /`<style>` skipped for visible tags. - 🚀 **Optional Non-Redirecting Prober**: Lightweight async HTTP client that treats 3xx redirects as actionable gate issues, with a 5 MiB body cap. Add this to your `Cargo.toml` : ``` [dependencies] indexflow-seo = "0.1.2" ``` `probe` *(default)*: Enables the async HTTP`SeoProbeClient` via`reqwest` (with pure Rustls TLS). ``` js use indexflow_seo::evaluate_html; fn main() { let page_url = "https://example.com/blog/rust-guide"; let html = r#" <!DOCTYPE html> <html lang="en"> <head> <title>Rust Monolith Guide & SEO Best Practices

Complete Guide to Rust Monolith

"#; let result = evaluate_html(page_url, 200, 25, None, html); if result.passed { println!("✅ SEO Gate: PASSED"); println!("Page Title: {:?}", result.page_title); println!("H1 Content: {:?}", result.h1_content); println!("Schema.org Entities: {:?}", result.schema_types()); } else { println!("❌ SEO Gate: BLOCKED (Reason: {:?})", result.block_reason); } } use indexflow_seo::SeoProbeClient; use std::time::Duration; #[tokio::main] async fn main() -> Result<(), Box> { let prober = SeoProbeClient::new( "Mozilla/5.0 (compatible; IndexFlowBot/1.0)", Duration::from_secs(10), )?; let result = prober.check_url("https://www.example.com").await; println!("Gate Result: passed={}, reason={:?}", result.passed, result.block_reason); println!("Response Time: {:?} ms", result.response_time_ms); println!("GPTBot Blocked: {}", result.ai_directives.gptbot_blocked); Ok(()) } ``` `indexflow-seo` enforces the following pre-flight checks before approving a URL for search engine submission: **HTTP Status**: Must strictly return`200 OK` .**Robots Directives**: Neither`` (or`none` ) nor`X-Robots-Tag: noindex` may be present.**Canonical Normalization**: Declared`` must match the page URL. Handles relative and protocol-relative paths,`.` /`..` segments, default ports 80/443, trailing slashes, scheme/host case, query-parameter order, and percent-encoding. Path case is preserved (case-sensitive).**Title Tag**: Must contain a valid, non-empty`` element. - Char-boundary-safe HTML scanner: CJK / emoji, quote-aware `>` , unquoted URL attributes, multiline meta, comments and raw`<script>` /`<style>` skipped for visible tags. - JSON-LD expands `@graph` , top-level arrays, and array-typed`@type` ; CDATA wrappers tolerated. - Single-pass entity decode (HTML named Latin-1 + `&#N;` /`&#xN;` ); no double-decode of`<` . - Canonical matching: sorted query params, `../` per RFC 3986, protocol-relative URLs,`%7E` ≡`~` . - GEO: AI-bot aliases, `none` /`noai` , per-bot`X-Robots-Tag` ; probe body capped at 5 MiB. Dual-licensed under either of: