does LangGraph support concurrent links?

[qiankunli]

Does LangGraph support concurrent links? For instance, with nodes named A, B, C, and D, if one starts from A and simultaneously running A to B and A to C, for node D, it can either wait for all upstream nodes B and C to complete their execution before proceeding with its own, or it can choose to execute immediately after one of the paths is completed (for example, if B finishes first while C is still in progress).

[Glinte]

LangGraph uses a limited form of concurrency. Everything works in terms of "supersteps". You described a diamond shaped graph, langgraph will run in three supersteps. A -> (B and C) -> D. D will not run while any part of the previous superstep is still in progress.

However, you are able to specify both types of dependency edges in langgraph.