Knock
Notification infrastructure with workflow engine.
Knock is a workflow-based notification platform: define workflows in code or visually, route across channels (email, push, SMS, in-app), and let users manage preferences. Email is delivered via your provider of choice.
Growth work lives or dies on targeting and measurement. What matters is whether behavioral triggers can be built without engineering time, whether the event stream supports attribution past the open, and whether deliverability holds when broadcast volume shares a reputation with product email.
Against behavior-triggered journeys, broadcasts, and winback campaigns measured on revenue, Knock covers scheduling, event stream, the suppressions API, and multi-tenant support, and does not cover operating track record. Whether that gap matters depends on how central those are to the build.
- Scheduling: Yes
- Event stream: Yes
- Deliverability: Inherits the deliverability of the provider you BYO (Postmark, SendGrid, Resend).
- Operating since: 2021
- Suppressions API: Yes
- Best published rate per 1,000: Tiers not published in comparable form
- Multi-tenant: Yes
- Free tier: 10,000 notifications/mo
- Starts at: $249/mo (Starter)
Inherits the deliverability of the provider you BYO (Postmark, SendGrid, Resend).
Teams that need multi-channel product notifications with preferences.
- › Strong workflow engine
- › In-app feed component
- › Deep SDK coverage
- › Idempotency keys
- › Pricier than running your own; entry plan is steep
- › Bring your own delivery provider
Features at a glance
| API | Yes |
| SMTP | No |
| SDKs | node, python, go, ruby, php, elixir, java, dotnet |
| Webhooks | Yes |
| Templates | rich |
| React Email | Yes |
| Batch send | Yes |
| Scheduled send | Yes |
| Suppressions | Yes |
| Multi-tenant | Yes |
| Inbound parsing | No |
| Event stream | Yes |
| Idempotency keys | Yes |
| Dedicated IP | No |