How to Export Real-Time-Capable LSTM to ONNX

I am having trouble getting a model with several LSTMs to export to ONNX properly. The main issue is that I intend to use the model in an online fashion, i.e. feeding in one frame of data at a time.

My LSTM code is similar to the following:

class MyLSTM(torch.nn.Module):
    def __init__(self, dim_in, dim_out):

        self.deployed = False

        self.hidden = torch.zeros(1, 1, dim_out)
        self.cell = torch.zeros(1, 1, dim_out)

        self.lstm = torch.nn.LSTM(input_size=dim_in,

    def deploy(self):
        self.deployed = True

    def forward(self, x):
        if self.deployed:
            out, (self.hidden, self.cell) = self.lstm(x, (self.hidden, self.cell))
            out, _ = self.lstm(x)

        return out

Obviously, before I export the model to ONNX, I call deploy(). The PyTorch model works as expected, and I even tried saving it as a ScriptModule with torch.jit. However, when I load and attempt to use the exported model using onnxruntime, it’s behavior suggests that it never updates the hidden/cell state.

Is it possible to do this? If so, how?