Deliver vs process failures (what retries actually mean)
Network timeouts and 5xx responses trigger automatic retries with backoff. Permanent 4xx responses stay visible in logs so teams can fix endpoint logic without hidden loops.
Webhook delivery + transactional email API for product events
SendPromptly gives SaaS teams reliable webhook delivery, transactional email, signed events, replay tooling, and delivery observability in one integration.
Works with your provider
Production-ready webhook delivery and transactional email
Cover transactional email and webhook delivery without building your own queue and retry stack.
Reliability
Webhook retries, idempotency, and delivery logs
Handle transient failures with built-in backoff and replay tools, while keeping one canonical message record.
- 5-attempt retry schedule
- Idempotency key support
- Replay and cancel flows
Developer Experience
Transactional email API + webhook API with predictable errors
Ship integrations quickly with predictable request and response schemas, versioned docs, and copyable examples.
- Bearer token auth
- Validation-first responses
- Rate limit guidance
Operations
Usage limits, scheduling, and policy controls
Apply quotas, schedule delays, and billing constraints without rebuilding policy logic in every application.
- Plan-level limits
- Usage period tracking
- Scheduled delivery support
How webhook delivery works (retries + replay + logs)
Track every delivery attempt from first send to final state so failures are visible, recoverable, and safe to replay.
Replay events safely (idempotency keys)
Replay failed or delayed events without duplicate side effects. Idempotency keys let your consumers process an event once even when retried or replayed later.
Verify signed events (HMAC + timestamp)
Signed webhook payloads and timestamp checks help block tampering and replay attacks, keeping inbound event processing trustworthy in production.
Use cases
Start with common event workflows and scale to product-specific automation as your platform grows.
Password resets and auth emails
Send account verification and recovery emails fast with delivery tracking and retry controls built in.
Billing and subscription events
Drive invoice, renewal, and dunning messages from one event stream with predictable policy controls.
Outbound webhooks to customer systems
Push product events to customer endpoints with signed payloads, retry visibility, and replay support.
Security and compliance built for production
Protect event integrity and simplify audits with production-grade security controls. Your team ships faster when security is handled.
Signed webhooks with HMAC
Every webhook includes HMAC signatures and timestamp validation to prevent tampering and replay attacks in production.
✓ Production-ready security
Complete audit trails
Audit-friendly delivery logs capture every retry attempt, replay action, and outcome for compliance and debugging.
✓ Compliance-ready logs
Secure implementation guides
Clear guidance for timing-safe signature comparisons and secure webhook consumer implementation patterns.
✓ Best practice docs
Why teams trust SendPromptly in production
Built for real-world event workflows where reliability, security, and operational visibility matter every day.
Reliable delivery when endpoints fail
Automatic retries and replay controls help you recover from transient failures without hand-rolled queue logic.
✓ Built-in retry and replay workflows
Security controls teams actually need
Signed webhook payloads, timestamp checks, and implementation guidance reduce risk in production consumers.
✓ Signed webhook verification patterns
Operational visibility for debugging and audits
Delivery logs capture attempts, outcomes, and replay actions so incident response and audits are straightforward.
✓ Full delivery history per event
Fast onboarding for engineering teams
A single API for transactional email and webhooks plus a free tier keeps evaluation and rollout friction low.
✓ Developer-first setup and docs
Start shipping reliable events in minutes
Launch quickly with retries, signatures, and delivery logs already built in.
Trusted by delivery-focused engineering teams
Teams use SendPromptly to avoid rebuilding message infrastructure on every product line.
Alicia Park
Staff Engineer, CometCart
We replaced three brittle jobs with one SendPromptly integration and cut incident noise immediately.
Marcus Young
CTO, FitLedger
Webhook signatures and retries are built in, so our team ships faster with less custom infrastructure.
Priya Iyer
Product Lead, RelayOps
The API is straightforward and the docs are clear enough for onboarding new engineers in an afternoon.
Ship reliable customer messaging this week
Start for free and send your first event in minutes.