diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
index 1583926ece..04fc0265f5 100644
--- a/.github/workflows/test.yml
+++ b/.github/workflows/test.yml
@@ -79,6 +79,9 @@ jobs:
           pip uninstall -y protobuf
           pip install --no-binary protobuf protobuf
 
+          pip install kaldifst
+          pip install onnxruntime
+
           pip install -r requirements.txt
 
       - name: Install graphviz
diff --git a/egs/librispeech/ASR/lstm_transducer_stateless/model.py b/egs/librispeech/ASR/lstm_transducer_stateless/model.py
index efbc88a55d..d71132b4ac 100644
--- a/egs/librispeech/ASR/lstm_transducer_stateless/model.py
+++ b/egs/librispeech/ASR/lstm_transducer_stateless/model.py
@@ -81,6 +81,7 @@ def forward(
         lm_scale: float = 0.0,
         warmup: float = 1.0,
         reduction: str = "sum",
+        delay_penalty: float = 0.0,
     ) -> Tuple[torch.Tensor, torch.Tensor]:
         """
         Args:
@@ -108,6 +109,11 @@ def forward(
             "sum" to sum the losses over all utterances in the batch.
             "none" to return the loss in a 1-D tensor for each utterance
             in the batch.
+          delay_penalty:
+            A constant value used to penalize symbol delay, to encourage
+            streaming models to emit symbols earlier.
+            See https://github.com/k2-fsa/k2/issues/955 and
+            https://arxiv.org/pdf/2211.00490.pdf for more details.
         Returns:
           Return the transducer loss.
 
@@ -164,6 +170,7 @@ def forward(
                 am_only_scale=am_scale,
                 boundary=boundary,
                 reduction=reduction,
+                delay_penalty=delay_penalty,
                 return_grad=True,
             )
 
@@ -196,6 +203,7 @@ def forward(
                 ranges=ranges,
                 termination_symbol=blank_id,
                 boundary=boundary,
+                delay_penalty=delay_penalty,
                 reduction=reduction,
             )
 
diff --git a/egs/librispeech/ASR/lstm_transducer_stateless/train.py b/egs/librispeech/ASR/lstm_transducer_stateless/train.py
index a50686df98..fbb4e72242 100755
--- a/egs/librispeech/ASR/lstm_transducer_stateless/train.py
+++ b/egs/librispeech/ASR/lstm_transducer_stateless/train.py
@@ -318,6 +318,16 @@ def get_parser():
         help="Whether to use half precision training.",
     )
 
+    parser.add_argument(
+        "--delay-penalty",
+        type=float,
+        default=0.0,
+        help="""A constant value used to penalize symbol delay,
+        to encourage streaming models to emit symbols earlier.
+        See https://github.com/k2-fsa/k2/issues/955 and
+        https://arxiv.org/pdf/2211.00490.pdf for more details.""",
+    )
+
     add_model_arguments(parser)
 
     return parser
@@ -611,6 +621,7 @@ def compute_loss(
             lm_scale=params.lm_scale,
             warmup=warmup,
             reduction="none",
+            delay_penalty=params.delay_penalty if warmup >= 2.0 else 0,
         )
         simple_loss_is_finite = torch.isfinite(simple_loss)
         pruned_loss_is_finite = torch.isfinite(pruned_loss)
diff --git a/egs/librispeech/ASR/lstm_transducer_stateless2/model.py b/egs/librispeech/ASR/lstm_transducer_stateless2/model.py
index b0fb6ab89c..fadeb4ac2f 100644
--- a/egs/librispeech/ASR/lstm_transducer_stateless2/model.py
+++ b/egs/librispeech/ASR/lstm_transducer_stateless2/model.py
@@ -106,6 +106,7 @@ def forward(
         lm_scale: float = 0.0,
         warmup: float = 1.0,
         reduction: str = "sum",
+        delay_penalty: float = 0.0,
     ) -> Tuple[torch.Tensor, torch.Tensor]:
         """
         Args:
@@ -136,6 +137,11 @@ def forward(
             "sum" to sum the losses over all utterances in the batch.
             "none" to return the loss in a 1-D tensor for each utterance
             in the batch.
+          delay_penalty:
+            A constant value used to penalize symbol delay, to encourage
+            streaming models to emit symbols earlier.
+            See https://github.com/k2-fsa/k2/issues/955 and
+            https://arxiv.org/pdf/2211.00490.pdf for more details.
         Returns:
           Return the transducer loss.
 
@@ -203,6 +209,7 @@ def forward(
                 am_only_scale=am_scale,
                 boundary=boundary,
                 reduction=reduction,
+                delay_penalty=delay_penalty,
                 return_grad=True,
             )
 
@@ -235,6 +242,7 @@ def forward(
                 ranges=ranges,
                 termination_symbol=blank_id,
                 boundary=boundary,
+                delay_penalty=delay_penalty,
                 reduction=reduction,
             )
 
diff --git a/egs/librispeech/ASR/lstm_transducer_stateless2/train.py b/egs/librispeech/ASR/lstm_transducer_stateless2/train.py
index 9eed2dfcb4..ac6bf7e048 100755
--- a/egs/librispeech/ASR/lstm_transducer_stateless2/train.py
+++ b/egs/librispeech/ASR/lstm_transducer_stateless2/train.py
@@ -341,6 +341,16 @@ def get_parser():
         help="The probability to select a batch from the GigaSpeech dataset",
     )
 
+    parser.add_argument(
+        "--delay-penalty",
+        type=float,
+        default=0.0,
+        help="""A constant value used to penalize symbol delay,
+        to encourage streaming models to emit symbols earlier.
+        See https://github.com/k2-fsa/k2/issues/955 and
+        https://arxiv.org/pdf/2211.00490.pdf for more details.""",
+    )
+
     add_model_arguments(parser)
 
     return parser
@@ -665,6 +675,7 @@ def compute_loss(
             lm_scale=params.lm_scale,
             warmup=warmup,
             reduction="none",
+            delay_penalty=params.delay_penalty if warmup >= 2.0 else 0,
         )
         simple_loss_is_finite = torch.isfinite(simple_loss)
         pruned_loss_is_finite = torch.isfinite(pruned_loss)
diff --git a/egs/librispeech/ASR/lstm_transducer_stateless3/train.py b/egs/librispeech/ASR/lstm_transducer_stateless3/train.py
index fa50576d8a..f2aa846258 100755
--- a/egs/librispeech/ASR/lstm_transducer_stateless3/train.py
+++ b/egs/librispeech/ASR/lstm_transducer_stateless3/train.py
@@ -328,6 +328,16 @@ def get_parser():
         help="Whether to use half precision training.",
     )
 
+    parser.add_argument(
+        "--delay-penalty",
+        type=float,
+        default=0.0,
+        help="""A constant value used to penalize symbol delay,
+        to encourage streaming models to emit symbols earlier.
+        See https://github.com/k2-fsa/k2/issues/955 and
+        https://arxiv.org/pdf/2211.00490.pdf for more details.""",
+    )
+
     add_model_arguments(parser)
 
     return parser
@@ -623,6 +633,7 @@ def compute_loss(
             lm_scale=params.lm_scale,
             warmup=warmup,
             reduction="none",
+            delay_penalty=params.delay_penalty if warmup >= 2.0 else 0,
         )
         simple_loss_is_finite = torch.isfinite(simple_loss)
         pruned_loss_is_finite = torch.isfinite(pruned_loss)
diff --git a/egs/librispeech/ASR/pruned_transducer_stateless/test_model.py b/egs/librispeech/ASR/pruned_transducer_stateless/test_model.py
index 1858d6bf02..fc82d8c69f 100755
--- a/egs/librispeech/ASR/pruned_transducer_stateless/test_model.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless/test_model.py
@@ -23,7 +23,6 @@
     python ./pruned_transducer_stateless/test_model.py
 """
 
-import torch
 from train import get_params, get_transducer_model
 
 
@@ -43,8 +42,6 @@ def test_model():
 
     num_param = sum([p.numel() for p in model.parameters()])
     print(f"Number of model parameters: {num_param}")
-    model.__class__.forward = torch.jit.ignore(model.__class__.forward)
-    torch.jit.script(model)
 
 
 def test_model_streaming():
@@ -63,8 +60,6 @@ def test_model_streaming():
 
     num_param = sum([p.numel() for p in model.parameters()])
     print(f"Number of model parameters: {num_param}")
-    model.__class__.forward = torch.jit.ignore(model.__class__.forward)
-    torch.jit.script(model)
 
 
 def main():
diff --git a/egs/librispeech/ASR/pruned_transducer_stateless2/model.py b/egs/librispeech/ASR/pruned_transducer_stateless2/model.py
index ba7616c610..417c391d9b 100644
--- a/egs/librispeech/ASR/pruned_transducer_stateless2/model.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless2/model.py
@@ -81,6 +81,7 @@ def forward(
         lm_scale: float = 0.0,
         warmup: float = 1.0,
         reduction: str = "sum",
+        delay_penalty: float = 0.0,
     ) -> Tuple[torch.Tensor, torch.Tensor]:
         """
         Args:
@@ -108,6 +109,12 @@ def forward(
             "sum" to sum the losses over all utterances in the batch.
             "none" to return the loss in a 1-D tensor for each utterance
             in the batch.
+          delay_penalty:
+            A constant value used to penalize symbol delay, to encourage
+            streaming models to emit symbols earlier.
+            See https://github.com/k2-fsa/k2/issues/955 and
+            https://arxiv.org/pdf/2211.00490.pdf for more details.
+        Returns:
         Returns:
           Return the transducer loss.
 
@@ -164,6 +171,7 @@ def forward(
                 am_only_scale=am_scale,
                 boundary=boundary,
                 reduction=reduction,
+                delay_penalty=delay_penalty,
                 return_grad=True,
             )
 
@@ -196,6 +204,7 @@ def forward(
                 ranges=ranges,
                 termination_symbol=blank_id,
                 boundary=boundary,
+                delay_penalty=delay_penalty,
                 reduction=reduction,
             )
 
diff --git a/egs/librispeech/ASR/pruned_transducer_stateless2/train.py b/egs/librispeech/ASR/pruned_transducer_stateless2/train.py
index 5c2f675345..7ce2ca7791 100755
--- a/egs/librispeech/ASR/pruned_transducer_stateless2/train.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless2/train.py
@@ -317,6 +317,16 @@ def get_parser():
         help="Whether to use half precision training.",
     )
 
+    parser.add_argument(
+        "--delay-penalty",
+        type=float,
+        default=0.0,
+        help="""A constant value used to penalize symbol delay,
+        to encourage streaming models to emit symbols earlier.
+        See https://github.com/k2-fsa/k2/issues/955 and
+        https://arxiv.org/pdf/2211.00490.pdf for more details.""",
+    )
+
     add_model_arguments(parser)
 
     return parser
@@ -607,6 +617,7 @@ def compute_loss(
             lm_scale=params.lm_scale,
             warmup=warmup,
             reduction="none",
+            delay_penalty=params.delay_penalty if warmup >= 2.0 else 0,
         )
         simple_loss_is_finite = torch.isfinite(simple_loss)
         pruned_loss_is_finite = torch.isfinite(pruned_loss)
diff --git a/egs/librispeech/ASR/pruned_transducer_stateless3/model.py b/egs/librispeech/ASR/pruned_transducer_stateless3/model.py
index 0d5f7cc6d9..7852f84e97 100644
--- a/egs/librispeech/ASR/pruned_transducer_stateless3/model.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless3/model.py
@@ -106,6 +106,7 @@ def forward(
         lm_scale: float = 0.0,
         warmup: float = 1.0,
         reduction: str = "sum",
+        delay_penalty: float = 0.0,
     ) -> Tuple[torch.Tensor, torch.Tensor]:
         """
         Args:
@@ -136,6 +137,11 @@ def forward(
             "sum" to sum the losses over all utterances in the batch.
             "none" to return the loss in a 1-D tensor for each utterance
             in the batch.
+          delay_penalty:
+            A constant value used to penalize symbol delay, to encourage
+            streaming models to emit symbols earlier.
+            See https://github.com/k2-fsa/k2/issues/955 and
+            https://arxiv.org/pdf/2211.00490.pdf for more details.
         Returns:
           Return the transducer loss.
 
@@ -203,6 +209,7 @@ def forward(
                 am_only_scale=am_scale,
                 boundary=boundary,
                 reduction=reduction,
+                delay_penalty=delay_penalty,
                 return_grad=True,
             )
 
@@ -235,6 +242,7 @@ def forward(
                 ranges=ranges,
                 termination_symbol=blank_id,
                 boundary=boundary,
+                delay_penalty=delay_penalty,
                 reduction=reduction,
             )
 
diff --git a/egs/librispeech/ASR/pruned_transducer_stateless3/train.py b/egs/librispeech/ASR/pruned_transducer_stateless3/train.py
index a74975caff..6cc34f18a1 100755
--- a/egs/librispeech/ASR/pruned_transducer_stateless3/train.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless3/train.py
@@ -328,6 +328,16 @@ def get_parser():
         help="The probability to select a batch from the GigaSpeech dataset",
     )
 
+    parser.add_argument(
+        "--delay-penalty",
+        type=float,
+        default=0.0,
+        help="""A constant value used to penalize symbol delay,
+        to encourage streaming models to emit symbols earlier.
+        See https://github.com/k2-fsa/k2/issues/955 and
+        https://arxiv.org/pdf/2211.00490.pdf for more details.""",
+    )
+
     add_model_arguments(parser)
     return parser
 
@@ -645,6 +655,7 @@ def compute_loss(
             lm_scale=params.lm_scale,
             warmup=warmup,
             reduction="none",
+            delay_penalty=params.delay_penalty if warmup >= 2.0 else 0,
         )
         simple_loss_is_finite = torch.isfinite(simple_loss)
         pruned_loss_is_finite = torch.isfinite(pruned_loss)
diff --git a/egs/librispeech/ASR/pruned_transducer_stateless4/train.py b/egs/librispeech/ASR/pruned_transducer_stateless4/train.py
index 4c55fd6096..57548270d0 100755
--- a/egs/librispeech/ASR/pruned_transducer_stateless4/train.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless4/train.py
@@ -335,6 +335,16 @@ def get_parser():
         help="Whether to use half precision training.",
     )
 
+    parser.add_argument(
+        "--delay-penalty",
+        type=float,
+        default=0.0,
+        help="""A constant value used to penalize symbol delay,
+        to encourage streaming models to emit symbols earlier.
+        See https://github.com/k2-fsa/k2/issues/955 and
+        https://arxiv.org/pdf/2211.00490.pdf for more details.""",
+    )
+
     add_model_arguments(parser)
 
     return parser
@@ -638,6 +648,7 @@ def compute_loss(
             lm_scale=params.lm_scale,
             warmup=warmup,
             reduction="none",
+            delay_penalty=params.delay_penalty if warmup >= 2.0 else 0,
         )
         simple_loss_is_finite = torch.isfinite(simple_loss)
         pruned_loss_is_finite = torch.isfinite(pruned_loss)
diff --git a/egs/librispeech/ASR/pruned_transducer_stateless5/train.py b/egs/librispeech/ASR/pruned_transducer_stateless5/train.py
index 1fa6682935..b964cd05d2 100755
--- a/egs/librispeech/ASR/pruned_transducer_stateless5/train.py
+++ b/egs/librispeech/ASR/pruned_transducer_stateless5/train.py
@@ -368,6 +368,16 @@ def get_parser():
         help="Whether to use half precision training.",
     )
 
+    parser.add_argument(
+        "--delay-penalty",
+        type=float,
+        default=0.0,
+        help="""A constant value used to penalize symbol delay,
+        to encourage streaming models to emit symbols earlier.
+        See https://github.com/k2-fsa/k2/issues/955 and
+        https://arxiv.org/pdf/2211.00490.pdf for more details.""",
+    )
+
     add_model_arguments(parser)
 
     return parser
@@ -662,6 +672,7 @@ def compute_loss(
             lm_scale=params.lm_scale,
             warmup=warmup,
             reduction="none",
+            delay_penalty=params.delay_penalty if warmup >= 2.0 else 0,
         )
         simple_loss_is_finite = torch.isfinite(simple_loss)
         pruned_loss_is_finite = torch.isfinite(pruned_loss)