It's cost me hundreds to thousands of dollars to implement nontrivial workflows because of how the YAML is parsed (for example, empty strings when using a secret that has been renamed or removed) and the lack of introspection or debuggability when something goes wrong.
It's gotten to the point where new any new workflows I write are thin wrappers around a single script and I don't import any actions besides actions/checkout (even that has been bug prone, historically).
All that said, it's not like other platforms are better. But they certainly are cheaper and don't have dumb breakages when you need cross platform builds (has upload-artifact been fixed for executables on MacOS yet?)
Workflows are statically typed in that they have event triggers - ideally with an event schema (which we generate for you) - and each "action" has static typing of inputs/outputs (plus additional workflow configuration for reusability). They're defined as code, and can be viewed or edited visually.
It also bundles an event hub, so you can automatically run workflows when events happen in real time. For example, if you want to run a churn flow on signup, create a workflow with a `signup.new` event trigger. The workflows can also coordinate between events, too, so in the churn workflow you can wait for an "interactivity" event from the user for up to 1 day, then time out and run some other flow/logic.
It's workflows, generalised. As if you put Github Workflows, Lambda, Segment, and Zapier in a blender.
If you want early access, you can always reach me at tony [at] inngest.com. I'm rolling out invites every week.