Yes — but usually that’s not the best pattern in Prefect. In Prefect 3.x, a flow can technically keep running forever, for example with a

while True:

loop. But Prefect is generally designed around discrete flow runs that start, do work, and then finish in a terminal state. Recommended approach - If you want something to run repeatedly, use a schedule or automation trigger - If you want something polling for work continuously, use: -

flow.serve(...)

for a long-lived process that creates flow runs over time - a worker for deployments in a work pool So the answer is: 1. Continuous infinite flow run: possible, but not ideal

from prefect import flow
import time

@flow
def my_flow():
    while True:
        print("doing work")
        time.sleep(5)

This works, but has downsides: - the flow run never reaches

Completed

- monitoring/retries are harder - if the process dies, that single long-lived run is interrupted - it can look like a stuck/zombie run if not handled carefully 2. Better: run continuously via scheduled flow runs If you want “always running every N seconds/minutes”, use

serve

or a deployment schedule. Example:

from prefect import flow

@flow
def my_flow():
    print("doing one unit of work")

if __name__ == "__main__":
    my_flow.serve(
        name="continuous-ish-flow",
        interval=60
    )

This means: - the runner process stays alive - Prefect creates a new flow run every 60 seconds - each run finishes cleanly 3. If you need event-driven behavior Use automations/events instead of an endless loop, depending on your use case. Helpful docs: - Serve flows - Interactive workflows - Workers Rule of thumb - Need a daemon/service? Use

serve

or an external service that triggers Prefect runs - Need periodic execution? Use schedules - Need one flow run to never exit? Possible, but generally not recommended If you want, I can show the best Prefect pattern for your specific case: - polling an API continuously - consuming a queue/stream - watching a folder - running a background service