diff --git a/.github/dependabot.yml b/.github/dependabot.yml
new file mode 100644
index 00000000..43b90890
--- /dev/null
+++ b/.github/dependabot.yml
@@ -0,0 +1,7 @@
+version: 2
+updates:
+  - package-ecosystem: "pip"
+    directory: "/"
+    schedule:
+      interval: "weekly"
+    open-pull-requests-limit: 10
diff --git a/README.md b/README.md
index 4fa8dd97..0c4fac3b 100644
--- a/README.md
+++ b/README.md
@@ -69,7 +69,7 @@ SynCode depends on HuggingFace [transformers](https://github.com/huggingface/tra
 
 | SynCode version | Required transformers version | Python version |
 | -------------- | ----------------------------- | -------------- |
-| `v0.4.11` (latest) | `v4.51.0`                    | 3.6 - 3.12     |
+| `v0.4.12` (latest) | `v4.51.0`                    | 3.6 - 3.12     |
 
 **Note:** Python 3.13 is not currently supported due to dependency constraints.
 
diff --git a/pyproject.toml b/pyproject.toml
index 89b68576..1d5c0baf 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -4,7 +4,7 @@ build-backend = "setuptools.build_meta"
 
 [project]
 name = "syncode"
-version="0.4.11"
+version="0.4.12"
 requires-python = ">=3.6,<3.13"
 description = "Grammar-guided code generation tool"
 readme = "README.md"
@@ -21,7 +21,7 @@ classifiers = [
 dependencies = [
     "fire",
     "interegular",
-    "regex==2023.8.8",
+    "regex==2024.11.6",
     "torch",
     "tqdm",
     "transformers==4.51.0",
diff --git a/requirements.txt b/requirements.txt
index aca1dee8..d9651c98 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,7 +1,7 @@
 accelerate
 fire
 interegular
-regex==2023.8.8
+regex==2024.11.6
 torch
 tqdm
 transformers==4.51.0; python_version < "3.13"
diff --git a/setup.py b/setup.py
index 9a78553d..f9b04013 100644
--- a/setup.py
+++ b/setup.py
@@ -8,7 +8,7 @@
 requirements = [
     "fire",
     "interegular",
-    "regex==2023.8.8",
+    "regex==2024.11.6",
     "torch",
     "tqdm",
     "transformers==4.51.0",
@@ -18,7 +18,7 @@
 
 setuptools.setup(
     name="syncode",
-    version="0.4.11",
+    version="0.4.12",
     author="Shubham Ugare",
     author_email="shubhamugare@gmail.com",
     description="This package provides the tool for grammar augmented LLM generation.",
diff --git a/syncode/mask_store/mask_store.py b/syncode/mask_store/mask_store.py
index 15ec1ef2..65cfdbc4 100644
--- a/syncode/mask_store/mask_store.py
+++ b/syncode/mask_store/mask_store.py
@@ -269,10 +269,10 @@ def _remove_left_whitespace(
         if (self._fsms.initial(fsm_state.terminal) == fsm_state or self._fsms.is_final(fsm_state)) and self._ignore_whitespace:
             if isinstance(remainder, bytes):
                 # For bytes, use lstrip() to remove all leading whitespace
-                remainder = remainder.lstrip()
+                remainder = remainder.lstrip(b' ')
             elif isinstance(remainder, str):
                 # For strings, use lstrip() to remove all leading whitespace
-                remainder = remainder.lstrip()
+                remainder = remainder.lstrip(' ')
         return remainder
 
     def _lookup_next_tokens_for_fsm_state(self, fsm_state: JointFSMState, next_terminal) -> torch.Tensor:
diff --git a/syncode/parsers/itergen_parser.py b/syncode/parsers/itergen_parser.py
index 3350c524..a7977dbf 100644
--- a/syncode/parsers/itergen_parser.py
+++ b/syncode/parsers/itergen_parser.py
@@ -102,7 +102,9 @@ def _update_symbol_pos_map_terminals(self, lexer_tokens: Iterable[Token], parsed
 
             # We don't add the last lexer token as it may change in the future
             # Essntially, we don't want IterGen to stop immediatelly after generating terminal which may extend in the future
-            start_idx -= 1
+            if start_idx > 0:
+                start_idx -= 1
+                
             end_idx = len(lexer_tokens)-1
 
             for idx in range(start_idx, end_idx):