How to Build a Zero-Dependency Email Verification Service Using Node.js

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A developer tutorial published on DEV Community demonstrates how to build a basic email verification service using only Node.js and its standard library, with no third-party packages required. The service checks email syntax, flags disposable, free, and role-based addresses, and performs MX record lookups via DNS. Checks are ordered by cost, with local syntax validation running first and the single network call — the MX lookup — running last with a 1,500ms timeout. The timeout is designed to resolve as inconclusive rather than rejecting a valid address, avoiding a common flaw in homegrown verifiers that treat DNS failures as invalid addresses. The approach suits developers who need SMTP-level checking, have high verification volumes, or must keep address data within their own network.

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Next.js, Supabase, and Vercel: A Practical Free-Tier Stack for Client Sites

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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ProgrammingDEV Community ·

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