SaaS Platform
Email Verification Platform
API-first email validation with syntax, domain, and mailbox checks—built for high volume and clean integration.
We designed and built a production email verification platform for teams that need reliable list hygiene before campaigns or onboarding flows. The product exposes a REST API, a queue-backed verification pipeline, and an operator dashboard for monitoring jobs, credits, and delivery quality.
The stack prioritizes predictable latency under burst traffic, clear error codes for integrators, and operational visibility when upstream DNS or mailbox providers slow down.
Challenge
The client needed to validate large contact lists without blocking their main application. Early prototypes ran checks synchronously and timed out on bulk uploads. Results were inconsistent across providers, and there was no audit trail for support or billing disputes.
They also required separation between real-time single-email checks and batch jobs that could take minutes, plus rate limits that would not starve interactive API callers.
Solution
We moved verification to an API-first architecture with dedicated worker processes. Uploads enqueue jobs in Redis; workers perform syntax validation, DNS/MX lookups, and mailbox probes with timeouts and retries tuned per stage.
Cached results reduce repeat cost for the same address, and each job stores structured status history. The dashboard surfaces queue depth, failure reasons, and exportable reports. Deployment runs on Linux with Docker Compose, TLS termination at Nginx, and environment-specific configuration for staging and production.
Key deliverables
- REST API with API keys and per-tenant rate limits
- Bulk CSV upload with progress and downloadable results
- Syntax, domain, MX, and mailbox verification stages
- Result caching with TTL to control cost and load
- Operator dashboard for jobs, credits, and audit logs
- Webhook callbacks when batch jobs complete
- Structured error codes for CRM and marketing integrations
- Health endpoints and log-friendly job identifiers for support
Outcome
The platform handles bulk verification asynchronously so customer-facing apps stay responsive. Integrators receive consistent JSON responses and documented error semantics. Operations can trace any address through the pipeline without reading raw server logs.