quien

quien is a command-line toolkit designed to provide comprehensive domain and IP intelligence through an interactive, tabbed terminal user interface. Developed as a replacement for the traditional whois command, it addresses the limitations of unformatted, registration-only outputs by offering a structured and multi-faceted view of domain and network data. The tool is suitable for users who need detailed insights into domains or IP addresses, such as IT professionals, security analysts, or researchers.

The toolkit presents information across several tabs, including WHOIS data (registrar, registration dates, nameservers, contacts with relative timestamps), DNS records (A, AAAA, CNAME, MX, NS, TXT, PTR, SOA, DNSSEC status), mail authentication (MX, SPF, DMARC, DKIM with selector probing, BIMI with VMC chain validation), SSL/TLS certificate details (including expiry, SANs), HTTP response headers (with security headers prioritized), SEO analysis (indexability, on-page elements, structured data, performance hints), and tech stack detection (CMS, WordPress plugins, JS/CSS frameworks, external services). For IP addresses, quien identifies the network owner, CIDR range, abuse contact, reverse DNS, ASN, and enriches data with PeeringDB for peering policy, traffic profile, and facility counts, using BGP as a fallback when necessary.

quien operates as a Go-based CLI with a TUI built on bubbletea and lipgloss, featuring automatic light/dark theming based on terminal background. It supports both interactive exploration and scripting: users can output results in JSON format or run targeted subcommands for specific data types such as whois, dns, mail, tls, http, seo, and stack. The tool primarily uses RDAP for lookups, covering over 1,200 TLDs, and automatically falls back to traditional WHOIS for unsupported TLDs. Tech stack detection is achieved by analyzing fetched HTML for known patterns. All lookups are retried automatically with exponential backoff to ensure reliability.

For SEO, quien performs local checks by default and can display Core Web Vitals field data if the user provides a Chrome UX Report API key. This includes metrics like LCP, INP, CLS, FCP, and TTFB, along with trend sparklines and ratings. sh. The tool was created by Ben Word.