Novu is a control story
Novu is compelling for teams that want to own more of their notification system. Open-source availability, self-hosting options, developer workflows, notification center use cases, and multi-channel notification logic all point to an infrastructure decision.
PostHog Workflows is not trying to be that. It is a way to act from product analytics.
That makes the comparison simple: do you need notification infrastructure, or do you need a product signal to trigger an action?
When PostHog Workflows is the better fit
Use PostHog Workflows when the event already exists in PostHog and the next step is clear. Send a simple email. Notify Slack. Call a webhook. Update a person property. Sync data to another destination.
There is no need to add a notification platform if the workflow is really a direct product action.
When Novu is the better fit
Use Novu when notifications are part of your product architecture. Users need an in-app center. Developers need a notification API. Different channels need routing. The team wants open-source control or self-hosting. Notification logic should be centralized instead of scattered through application code.
PostHog can still provide events, but Novu should own the notification layer.
Where Sequenzy fits
Sequenzy is not for building an in-app notification center. It is for SaaS email: onboarding, activation, transactional notices, billing messages, and retention campaigns.
If that is the real work, Sequenzy is a more focused choice than an open-source notification platform.
Practical rule
Use PostHog Workflows when analytics should trigger an action.
Use Novu when the product needs notification infrastructure.
Use Sequenzy when the business needs SaaS email workflows.