Developer builds emoji-linting tool that halts site deploys on style violations

A developer managing a fleet of static sites created a custom linting tool called emoji-lint to automatically enforce a house style rule banning emoji from published content. The tool scans HTML files using a Unicode regex and exits with an error code if any emoji is detected, blocking the day's deployment until the issue is resolved. Building the tool into real operation revealed three legitimate exceptions: verbatim quotes from others, proper nouns with official symbol-containing spellings, and content where emoji is itself the subject. To handle these cases without weakening the rule, the tool uses a 'masking' approach that blanks out exempt content before scanning, preserving line numbers for accurate error reporting. Safeguards were added to prevent abuse, such as rejecting allowlist entries made up entirely of symbols, ensuring the exemption system cannot be exploited to bypass the rule entirely.