MailCheck Developer Documentation

// 1. Install official SDK: npm install @fadsync/mailcheck-edge
const express = require('express');
const { mailCheckGuard } = require('@fadsync/mailcheck-edge');

const app = express();
app.use(express.json());

// Protect signup route with 1-line Express middleware
app.post('/api/auth/register', 
  mailCheckGuard({ 
    apiKey: process.env.FADSYNC_API_KEY, 
    blockDisposable: true,
    blockDeadMx: true
  }), 
  (req, res) => {
    // req.mailCheck contains verified validation results
    res.json({ message: "Registration successful!", risk: req.mailCheck.riskScore });
  }
);

# 1. Install: pip install "fadsync-mailcheck[fastapi]"
from fastapi import FastAPI, Depends, status
from pydantic import BaseModel, EmailStr
from fadsync_mailcheck import FastAPIEmailGuard, ValidationResult

app = FastAPI()
email_guard = FastAPIEmailGuard(api_key="YOUR_FADSYNC_API_KEY", block_disposable=True)

class SignupRequest(BaseModel):
    name: str
    email: EmailStr

@app.post("/api/signup", status_code=status.HTTP_201_CREATED)
async def signup(
    payload: SignupRequest,
    check: ValidationResult = Depends(lambda req: email_guard(req.email))
):
    # Rejects 40M+ burner emails & dead MX with HTTP 422 automatically
    return {"status": "verified", "risk_score": check.risk_score}

// 1. Add to pubspec.yaml: flutter pub add flutter_fadsync_email_validator
import 'package:flutter/material.dart';
import 'package:flutter_fadsync_email_validator/flutter_fadsync_email_validator.dart';

// Drop-in form field with real-time debounce & typo autocorrect
FadSyncEmailFormField(
  apiKey: "YOUR_FADSYNC_API_KEY",
  blockDisposable: true,
  enableTypoAutocorrect: true,
  decoration: InputDecoration(
    labelText: "Work Email Address",
    prefixIcon: Icon(Icons.email_outlined),
  ),
  onValidated: (result) {
    print("Risk score: ${result.riskScore}, Disposable: ${result.isDisposable}");
  },
)

// 1. Install official SDK: npm install @fadsync/mailcheck-edge
const { FadSyncMailCheck } = require('@fadsync/mailcheck-edge');

const mailcheck = new FadSyncMailCheck({
  apiKey: process.env.FADSYNC_API_KEY,
  failSilent: true, // Graceful fallback on network blips
  cacheTtlMs: 300000 // Sub-50ms in-memory TTL cache
});

async function handleSignup(req, res) {
  const result = await mailcheck.verify(req.body.email);

  if (result.isBlocked) {
    return res.status(422).json({
      success: false,
      error: result.userFriendlyMessage,
      isDisposable: result.isDisposable,
      suggestedEmail: result.typoFix
    });
  }

  // Proceed with registration...
  res.json({ success: true, riskScore: result.riskScore });
}

curl --request POST \
  --url https://mailcheck.fadsync.com/api/v1/bulk \
  --header 'Content-Type: application/json' \
  --header 'Authorization: Bearer YOUR_FADSYNC_API_KEY' \
  --data '{"emails": ["user1@gmail.com", "fake@trashmail.com"]}'

curl --request GET \
  --url 'https://mailcheck.fadsync.com/api/v1/domain?domain=trashmail.com' \
  --header 'Authorization: Bearer YOUR_FADSYNC_API_KEY'