const checkAvailability = debounce(async (value) => , 500);

INSERT INTO kamalogam_reserved_usernames VALUES ('admin'), ('kamalogam'), ('support'), ('moderator'); // POST /api/check-username app.post('/api/check-username', async (req, res) => const username = req.body; // 1. Validation rules const usernameRegex = /^[a-zA-Z0-9._]3,20$/; if (!usernameRegex.test(username)) return res.json( available: false, reason: '3-20 characters, letters, numbers, underscore, or dot only.' );

"available": false, "reason": "Username already taken.", "suggestions": ["john_doe_123", "john_doe_art", "johndoe_"]

// 2. Check reserved list const reserved = await db.query( 'SELECT 1 FROM kamalogam_reserved_usernames WHERE name = $1', [username.toLowerCase()] ); if (reserved.rows.length > 0) return res.json( available: false, reason: 'This username is reserved.' );

useEffect(() => checkAvailability(username); , [username]);