The workflow tracks the workflow execution and status in a DynamoDB table. When the workflow starts, an idempotency key is calculated based on the input event (customizable) and stored in the database as a semaphore together with a status of `IN_PROGRESS`.

If storing the key was successful, the workflow runs the actual workflow steps and records the result in the database with a status of `SUCCESS` (or `FAILED` in case of an error).

If acquiring the semaphore was not successful (i.e. the workflow successfully executed previously or another execution is running concurrently and thus the status is `IN_PROGRESS`) the workflow retrieves the idempotency record from the database. When the status is `SUCCESS` and there is a result the result is returned as output of the workflow. If the status is `IN_PROGRESS` the workflow continues to query the database every 10 seconds until the status changes to either `SUCCESS` and it continues as described above, or `FAILED`, in which case the workflow tries to acquire the semaphore again.