Knock
Hosted notification workflows; Developer free to 10k messages/mo
Comms / Notifications · Freemium
What's Good
Workflows + preferences + in-app feeds/guides across email, push, SMS, Slack, Teams, Discord. Developer $0: 10k messages/mo, unlimited workflows/channels/members, batch/delay, multi-tenancy, Google SSO. SDKs + CLI. Charge only for messages sent (not failed/bounced triggers).
The Catch
Closed-source SaaS — not Novu MIT self-host. LOUD: Starter jumps to $250/mo (50k messages). Downstream SendGrid/Twilio/etc still bill you. HIPAA/SAML/SCIM are Enterprise. Free path is Developer tier only.
Verdict
Hosted notification workflows. Free to 10k msgs; Starter $250. Not self-hostable.
Embed
[](https://stackgems.com/gems/knock)