liftAsyncWorking.fs

type Response = { StatusCode : int }

// Simulate sync action, that returns count of records synced
let syncRecords upToTimestamp = ResultT <| async.Return (Ok 3)
    
// Simulate bookmark function, sending last timestamp synced to a rest api
let recordTimestamp upToTimestamp = async {
    return {StatusCode = 200 }
}

let performSync () =
    let utcNow = DateTime.UtcNow
    monad {
        let! count = syncRecords utcNow
        let! response = recordTimestamp utcNow |> liftAsync
        if response.StatusCode < 200 || response.StatusCode >= 300 then
            printfn "Sync succeeded, but failed to update bookmark"
        return count
    }