RemoteRunnable is deprecated. What is the alternative?

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1

I have an app that is still using Langserve. In the client (js), we use a RemoteRunnable to call a runnable in the backend (python). However, RemoteRunnable is deprecated and the docs just says to update to the LangGraph platform. However, since it would be less than optimal to move everything over at this point, what is the best alternative/easiest/suggested way to replace RemoteRunnable? Just convert the end point to a plain FastApi endpoint and do an http call in the frontend? Something else within the LangChain ecosystem?

	const remoteChain = new RemoteRunnable({
		url: ExternalURLs.agent,
		options: {
			timeout: timeout, 
			headers: headers,
		},
	});

	const response = await remoteChain.invoke({
		messages: [messageText]
	})
2

Hey Juan,

It’s marked as deprecated because we deprecated LangServe. It’s not in active development and might be removed at some point in the future (but not soon).

If you want to keep using RemoteRunnable, you can copy over the source code and just use it!
Your approach of setting up a FastAPI server also works.

3

Thanks for the info @nhuang !

4

langServe is the preferred deployment platform for langgraph agents, why is it being deprecated?
what is the best runtime we should pick for langraph agents deployed on langserve?
my question is regarding this docs

5

LangServe has been deprecated for a long time and was designed for deploying LCEL chains rather than langgraph agents – langsreve was created long before langgraph existed. We also deprecated it a long time and we have a much much better option for deploying langgraph agents!

You can get started with deployment for langgraph here: Run a local server - Docs by LangChain