Knock

Knock is a customer engagement platform that unifies product, marketing, and transactional messaging in a single system, with agent-led capabilities for building and editing messaging flows. It addresses a structural problem most organisations recognise immediately: product notifications are built by engineers, marketing campaigns run in a separate ESP, and transactional mail lives somewhere else entirely, with nobody holding a complete view of what a customer actually receives.

That fragmentation has real consequences. Customers get a lifecycle email and a product notification about the same event within minutes of each other. Preference management is inconsistent, so unsubscribing from one stream does not stop another. Nobody can answer how many messages a given customer received last week. Consolidating onto one messaging layer makes cross-channel orchestration, frequency capping, and unified preferences achievable rather than aspirational, and gives marketing visibility into communications it never previously controlled.

The cost of that consolidation is that it is a platform migration, not a tool purchase. Notification infrastructure is deeply wired into a product, so adoption means engineering work and a real project plan, which puts it firmly in the category of decisions a CMO makes jointly with a CTO. Teams whose messaging is genuinely simple, a single ESP and a handful of transactional emails, will find this heavier than the problem warrants. Teams drowning in fragmented customer communication will find it addresses the actual cause.