Email, SMS, and WhatsApp aren't the only way notifications leave your system. Most B2B integrations are still webhooks — and the difference between a webhook that works and one that quietly breaks is everything that surrounds the HTTP call. 4notify treats webhooks as a first-class channel with the same delivery guarantees we apply to user-facing messages.
Each capability ships on the standard plan. Nothing in this list is an upsell or a separate product line.
Every outbound request is HMAC-signed with a secret that rotates on demand. Customers verify with three lines of code and can see the exact payload that produced the signature inside their portal — no more 'the webhook arrived but didn't validate' tickets.
Failed deliveries retry on an exponential schedule with full jitter. Every attempt is recorded; you can replay a single event, a date range, or everything that failed during an outage with one click — and a unique idempotency key per event makes the receiving side safe.
A single 'invoice.paid' event can simultaneously hit your accounting webhook, a Slack channel, a fulfillment partner, and your data warehouse. Each endpoint has its own retry policy and filters — you don't end up with one slow consumer holding up the others.
If a customer's endpoint starts 500-ing under load, we slow that delivery without affecting the rest of the queue. Sustained failures trip a circuit breaker and notify the customer admin — they find out before their next quarterly review.
The relay shares the same observability stack as the email and SMS channels — every payload, every retry, every signature mismatch lives in the message audit log with full search.
REST and SMTP endpoints for receipts, password resets, and product alerts — built for US sender requirements.
10DLC, toll-free and short-code SMS for customer alerts, MFA, and field-service updates.
Official Cloud API access for utility, authentication, and customer-care conversations.
Move beyond one-off sends. Trigger flows from product events, sequence messages across channels, and adapt copy to who is reading it.
Know what happened to every message — and why — without piecing it together from carrier exports and inbox screenshots.
