A programming model provides a method for executing a program in a distributed architecture. One or more first shards of the distributed architecture execute one or more operations, and sending tuples to at least one second shard, the tuples being part of a stream and being based on the one or more operations. The one or more first shards send a token value to the at least one second shard when the sending of the tuples in the stream is complete. The at least one second shard determines whether a total of the token values matches a number of the one or more first shards, and takes a first action in response to determining that the total of the token values matches the number of the one or more first shards. The first action may include marking the stream as being complete and/or generating a message indicating that the stream is complete.