Knock is a product and customer messaging infrastructure. You can use Knock to power all of your product's messaging needs, including transactional messaging, lifecycle marketing, one-time announcements, and in-product messaging, without the effort of building and maintaining your own in-house messaging system.
Knock is made with engineering, product, growth, and operations teams in mind. It's easy for developers to implement, and simple for less-technical users to maintain in our dashboard.
This is the 4th launch from Knock. View more
Knock data sources
Launched this week
Knock data sources enable you to ingest event data from any tool to trigger messaging in a few clicks—no code required. Connect pre-built sources like Stripe, Clerk, Supabase, PostHog, and WorkOS, or map any custom webhook to workflows, audiences, and user updates in a few clicks. Knock handles verification, transformation, and action mapping so you can launch lifecycle and transactional messaging faster.
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Launch Team
Knock
Over the years, I’ve found that most teams responsible for messaging are most limited by their lack of access to real-time data.
The hard part is not designing the email, push, or in-app message… It’s getting the right event data from the rest of your stack into your messaging system in a way that is reliable, flexible, and fast enough to actually use.
We’re launching data sources today to solve that problem.
With data sources, you can connect events from tools like Stripe, Clerk, Supabase, PostHog, and WorkOS directly into Knock and map them to actions like triggering workflows, updating users, or syncing audiences. You can leverage pre-configured data sources, or map in custom tools, too.
Now, when something important happens anywhere in your stack, it’s easy to turn that into a messaging experience:
Send an ‘update billing info’ alert when a Stripe payment fails.
Trigger an onboarding sequence when a user is created in WorkOS.
Create user segments based on product usage activity in Posthog.
A lot of messaging software still assumes your data arrives in exactly the right format, from a narrow set of supported integrations. That breaks down quickly in the real world. Every company has a different stack, different schemas, and different events.
What makes data sources useful is not just that it connects tools. It removes a lot of the work that usually sits between the event and the action:
no custom middleware just to reshape payloads
no separate verification layer for sensitive events
no waiting on engineering for every new source or mapping
Data sources is a step toward a more flexible model: connect whatever emits events, verify and transform the payload, and map it to the action you want in a few clicks.
Check it out, and tell us what you think. What other tools do you plan to connect?
payment events are easy. behavior-driven triggers (user didn't finish onboarding, churned 7 days after last event) get gnarly fast. most tools struggle with multi-condition logic. how are you handling it?
Knock
@mykola_kondratiuk Totally agree — one-step flows are easy (even easier now, with data sources). Gets a little more complex when the use case has more variables, but not too hard with the right data, tools, and logic.
How I see it, data sources handle event ingestion, and then all the necessary conditional logic lives in audiences and workflows. So for something like “didn’t finish onboarding,” you’d typically combine product events, user properties, and timing rules to define that state once, then use it to trigger messaging.
Same idea for cases like “churned 7 days after last event” — that’s usually a mix of event history, conditional logic, and time-based eval rather than a single trigger. We support that by letting teams branch on user data and events, use relative time conditions, set exclusion rules, etc.
So yeah, in practice, all event-based messaging scenarios are def not simple one-step triggers, but data sources can be combined with the rest of Knock to power some really complex flows.
yeah, that's where it gets interesting - multi-conditional routing with state across channels is where most teams hit the ceiling
Knock
Connect any tool to Knock in minutes. I'm stoked about this release! 🚀
Launch OS
This is just amazing product. D you guys provide personal on call onboarding?
Its been a while seeing a very solid product and as well as what a wonderful pricing. This will go long way!! Looking forward.