Static localhost configuration review

Framework Config Linter

Paste a development-server configuration to find port ambiguity, network exposure, permissive host or CORS settings, and framework-specific mistakes.

The snippet is inspected locally and never executed or uploaded.

Configuration snippet

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Framework

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Paste configuration or command

This is a focused pattern-based review, not a full parser or a substitute for running the framework’s own validation.

Configuration findings

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What this linter checks

Reachability

Port and bind address

Distinguishes loopback-only settings from wildcard binds that may expose a development server to the LAN.

Predictability

Fallbacks and overrides

Flags ambiguous port sources, framework defaults, and settings such as Vite port fallback or Next.js environment placement.

Trust boundary

Hosts, CORS, debug, secrets

Looks for permissive development settings and client-visible environment variable names that deserve manual review.

Validate the live process too

Static configuration can be overridden by a command, environment variable, container, or parent process. Confirm the effective listener with the Port Command Generator, then decode its output with the Port Output Parser.