public interface IPipeline {
    Task Start();
    Task Cycle();
    Task Stop();
}

...

protected override async Task ExecuteAsync(CancellationToken stoppingToken) {
    log.LogInformation($"Starting subsystems");

    foreach(var engine in pipeLine) {
        try {
            await engine.Start();
        }
        catch(Exception ex) {
            log.LogError(ex, $"{nameof(engine)} failed to start");
        }
    }

    log.LogInformation($"Runnning main loop");

    while(!stoppingToken.IsCancellationRequested) {
        foreach(var engine in pipeLine) {
            try {
                await engine.Cycle();
            }
            catch(Exception ex) {
                log.LogError(ex, $"{engine.GetType().Name} error in Cycle");
            }
        }
    }

    log.LogInformation($"Stopping subsystems");

    foreach(var engine in pipeLine) {
        try {
            await engine.Stop();
        }
        catch(Exception ex) {
            log.LogError(ex, $"{nameof(engine)} failed to stop");
        }
    }
}

public async Task Cycle() {
    await Task.CompletedTask;
}

public async Task Cycle() {
    await Task.Delay(1);
}