diff --git a/ell-studio/src/components/LMPDetailsSidePanel.js b/ell-studio/src/components/LMPDetailsSidePanel.js
index a24ac983..1fefb23c 100644
--- a/ell-studio/src/components/LMPDetailsSidePanel.js
+++ b/ell-studio/src/components/LMPDetailsSidePanel.js
@@ -28,7 +28,7 @@ function VersionItem({ version, index, totalVersions, currentLmpId }) {
           {isLatest && <span className="text-xs bg-green-500 text-white px-2 py-0.5 rounded">Latest</span>}
         </div>
         <div className="text-xs text-gray-500 mt-1">
-          {getTimeAgo(new Date(version.created_at + "Z"))}
+          {getTimeAgo(new Date(version.created_at))}
         </div>
       </Link>
     </div>
diff --git a/src/ell/decorators/track.py b/src/ell/decorators/track.py
index 8dc7aa1b..fe726240 100644
--- a/src/ell/decorators/track.py
+++ b/src/ell/decorators/track.py
@@ -1,5 +1,5 @@
 import logging
-from ell.types import SerializedLStr
+from ell.types import SerializedLStr, utc_now
 import ell.util.closure
 from ell.configurator import config
 from ell.lstr import lstr
@@ -86,7 +86,7 @@ def wrapper(*fn_args, **fn_kwargs) -> str:
                 logger.info(f"Attempted to use cache on {func_to_track.__qualname__} but it was not cached, or did not exist in the store. Refreshing cache...")
         
         
-        _start_time = datetime.now()
+        _start_time = utc_now()
 
         # XXX: thread saftey note, if I prevent yielding right here and get the global context I should be fine re: cache key problem
 
@@ -96,7 +96,7 @@ def wrapper(*fn_args, **fn_kwargs) -> str:
             if not lmp
             else fn(*fn_args, _invocation_origin=invocation_id, **fn_kwargs, )
             )
-        latency_ms = (datetime.now() - _start_time).total_seconds() * 1000
+        latency_ms = (utc_now() - _start_time).total_seconds() * 1000
         usage = metadata.get("usage", {})
         prompt_tokens=usage.get("prompt_tokens", 0)
         completion_tokens=usage.get("completion_tokens", 0)
@@ -145,7 +145,7 @@ def _serialize_lmp(func, name, fn_closure, is_lmp, lm_kwargs):
         config._store.write_lmp(
             lmp_id=func.__ell_hash__,
             name=name,
-            created_at=datetime.now(),
+            created_at=utc_now(),
             source=fn_closure[0],
             dependencies=fn_closure[1],
             commit_message=commit,
@@ -162,7 +162,7 @@ def _write_invocation(func, invocation_id, latency_ms, prompt_tokens, completion
     config._store.write_invocation(
         id=invocation_id,
         lmp_id=func.__ell_hash__,
-        created_at=datetime.now(),
+        created_at=utc_now(),
         global_vars=get_immutable_vars(func.__ell_closure__[2]),
         free_vars=get_immutable_vars(func.__ell_closure__[3]),
         latency_ms=latency_ms,
diff --git a/src/ell/store.py b/src/ell/store.py
index 02a46ffc..11348a35 100644
--- a/src/ell/store.py
+++ b/src/ell/store.py
@@ -1,5 +1,6 @@
 from abc import ABC, abstractmethod
 from contextlib import contextmanager
+from datetime import datetime
 from typing import Any, Optional, Dict, List, Set, Union
 from ell.lstr import lstr
 from ell.types import InvocableLM
@@ -15,7 +16,7 @@ def write_lmp(self, lmp_id: str, name: str, source: str, dependencies: List[str]
                   version_number: int,
                   uses: Dict[str, Any], 
                   commit_message: Optional[str] = None,
-                  created_at: Optional[float]=None) -> Optional[Any]:
+                  created_at: Optional[datetime]=None) -> Optional[Any]:
         """
         Write an LMP (Language Model Package) to the storage.
 
@@ -33,7 +34,7 @@ def write_lmp(self, lmp_id: str, name: str, source: str, dependencies: List[str]
 
     @abstractmethod
     def write_invocation(self, id: str, lmp_id: str, args: str, kwargs: str, result: Union[lstr, List[lstr]], invocation_kwargs: Dict[str, Any], 
-                         created_at: Optional[float], consumes: Set[str], prompt_tokens: Optional[int] = None,
+                         created_at: Optional[datetime], consumes: Set[str], prompt_tokens: Optional[int] = None,
                          completion_tokens: Optional[int] = None, latency_ms: Optional[float] = None,
                          state_cache_key: Optional[str] = None,
                          cost_estimate: Optional[float] = None) -> Optional[Any]:
diff --git a/src/ell/stores/sql.py b/src/ell/stores/sql.py
index 2bcbac6e..7e32e18b 100644
--- a/src/ell/stores/sql.py
+++ b/src/ell/stores/sql.py
@@ -1,4 +1,4 @@
-import datetime
+from datetime import datetime
 import json
 import os
 from typing import Any, Optional, Dict, List, Set, Union
@@ -7,7 +7,7 @@
 import cattrs
 import numpy as np
 from sqlalchemy.sql import text
-from ell.types import InvocationTrace, SerializedLMP, Invocation, SerializedLMPUses, SerializedLStr
+from ell.types import InvocationTrace, SerializedLMP, Invocation, SerializedLMPUses, SerializedLStr, utc_now
 from ell.lstr import lstr
 from sqlalchemy import or_, func, and_
 
@@ -26,7 +26,7 @@ def write_lmp(self, lmp_id: str, name: str, source: str, dependencies: List[str]
                   global_vars: Dict[str, Any],
                   free_vars: Dict[str, Any],
                   commit_message: Optional[str] = None,
-                  created_at: Optional[float]=None) -> Optional[Any]:
+                  created_at: Optional[datetime]=None) -> Optional[Any]:
         with Session(self.engine) as session:
             lmp = session.query(SerializedLMP).filter(SerializedLMP.lmp_id == lmp_id).first()
             
@@ -42,7 +42,7 @@ def write_lmp(self, lmp_id: str, name: str, source: str, dependencies: List[str]
                     dependencies=dependencies,
                     initial_global_vars=global_vars,
                     initial_free_vars=free_vars,
-                    created_at= created_at or datetime.datetime.utcnow(),
+                    created_at= created_at or utc_now(),
                     is_lm=is_lmp,
                     lm_kwargs=lm_kwargs,
                     commit_message=commit_message
diff --git a/src/ell/types.py b/src/ell/types.py
index ee5bb44d..eb5a4ead 100644
--- a/src/ell/types.py
+++ b/src/ell/types.py
@@ -1,14 +1,15 @@
 # Let's define the core types.
 from dataclasses import dataclass
-from typing import Callable, Dict, List, Union
+from typing import Callable, Dict, List, Union, Any, Optional
 
-from typing import Any
 from ell.lstr import lstr
 from ell.util.dict_sync_meta import DictSyncMeta
 
-from datetime import datetime
+from datetime import datetime, timezone
 from typing import Any, List, Optional
-from sqlmodel import Field, SQLModel, Relationship, JSON, ARRAY, Column, Float
+from sqlmodel import Field, SQLModel, Relationship, JSON, Column
+from sqlalchemy import func
+import sqlalchemy.types as types
 
 _lstr_generic = Union[lstr, str]
 
@@ -43,6 +44,14 @@ class Message(dict, metaclass=DictSyncMeta):
 InvocableLM = Callable[..., _lstr_generic]
 
 
+def utc_now() -> datetime:
+    """
+    Returns the current UTC timestamp.
+    Serializes to ISO-8601.
+    """
+    return datetime.now(tz=timezone.utc)
+
+
 class SerializedLMPUses(SQLModel, table=True):
     """
     Represents the many-to-many relationship between SerializedLMPs.
@@ -54,6 +63,16 @@ class SerializedLMPUses(SQLModel, table=True):
     lmp_using_id: Optional[str] = Field(default=None, foreign_key="serializedlmp.lmp_id", primary_key=True, index=True)  # ID of the LMP that is using the other LMP
 
 
+class UTCTimestamp(types.TypeDecorator[datetime]):
+    impl = types.TIMESTAMP
+    def process_result_value(self, value: datetime, dialect:Any):
+        return value.replace(tzinfo=timezone.utc)
+
+def UTCTimestampField(index:bool=False, **kwargs:Any):
+    return Field(
+        sa_column= Column(UTCTimestamp(timezone=True),index=index, **kwargs))
+        
+
 
 class SerializedLMP(SQLModel, table=True):
     """
@@ -65,7 +84,11 @@ class SerializedLMP(SQLModel, table=True):
     name: str = Field(index=True)  # Name of the LMP
     source: str  # Source code or reference for the LMP
     dependencies: str  # List of dependencies for the LMP, stored as a string
-    created_at: datetime = Field(default_factory=datetime.utcnow, index=True)  # Timestamp of when the LMP was created
+    # Timestamp of when the LMP was created
+    created_at: datetime = UTCTimestampField(
+        index=True,
+        nullable=False
+    )
     is_lm: bool  # Boolean indicating if it is an LM (Language Model) or an LMP
     lm_kwargs: dict  = Field(sa_column=Column(JSON)) # Additional keyword arguments for the LMP
 
@@ -131,8 +154,8 @@ class Invocation(SQLModel, table=True):
     completion_tokens: Optional[int] = Field(default=None)
     state_cache_key: Optional[str] = Field(default=None)
 
-    
-    created_at: datetime = Field(default_factory=datetime.utcnow)  # Timestamp of when the invocation was created
+    # Timestamp of when the invocation was created
+    created_at: datetime = UTCTimestampField(default=func.now(), nullable=False)
     invocation_kwargs: dict = Field(default_factory=dict, sa_column=Column(JSON))  # Additional keyword arguments for the invocation
 
     # Relationships
diff --git a/tests/test_sql_store.py b/tests/test_sql_store.py
new file mode 100644
index 00000000..a8b854ae
--- /dev/null
+++ b/tests/test_sql_store.py
@@ -0,0 +1,88 @@
+import pytest
+from datetime import datetime, timezone
+from sqlmodel import Session, select
+from ell.stores.sql import SQLStore, SerializedLMP
+from sqlalchemy import Engine, create_engine
+
+from ell.types import utc_now
+
+@pytest.fixture
+def in_memory_db():
+    return create_engine("sqlite:///:memory:")
+
+@pytest.fixture
+def sql_store(in_memory_db: Engine) -> SQLStore:
+    store = SQLStore("sqlite:///:memory:")
+    store.engine = in_memory_db
+    SerializedLMP.metadata.create_all(in_memory_db)
+    return store
+
+def test_write_lmp(sql_store: SQLStore):
+    # Arrange
+    lmp_id = "test_lmp_1"
+    name = "Test LMP"
+    source = "def test_function(): pass"
+    dependencies = str(["dep1", "dep2"])
+    is_lmp = True
+    lm_kwargs = '{"param1": "value1"}'
+    version_number = 1
+    uses = {"used_lmp_1": {}, "used_lmp_2": {}}
+    global_vars = {"global_var1": "value1"}
+    free_vars = {"free_var1": "value2"}
+    commit_message = "Initial commit"
+    created_at = utc_now()
+    assert created_at.tzinfo is not None
+
+    # Act
+    sql_store.write_lmp(
+        lmp_id=lmp_id,
+        name=name,
+        source=source,
+        dependencies=dependencies,
+        is_lmp=is_lmp,
+        lm_kwargs=lm_kwargs,
+        version_number=version_number,
+        uses=uses,
+        global_vars=global_vars,
+        free_vars=free_vars,
+        commit_message=commit_message,
+        created_at=created_at
+    )
+
+    # Assert
+    with Session(sql_store.engine) as session:
+        result = session.exec(select(SerializedLMP).where(SerializedLMP.lmp_id == lmp_id)).first()
+        
+        assert result is not None
+        assert result.lmp_id == lmp_id
+        assert result.name == name
+        assert result.source == source
+        assert result.dependencies == str(dependencies)
+        assert result.is_lm == is_lmp
+        assert result.lm_kwargs == lm_kwargs
+        assert result.version_number == version_number
+        assert result.initial_global_vars == global_vars
+        assert result.initial_free_vars == free_vars
+        assert result.commit_message == commit_message
+        # we want to assert created_at has timezone information
+        assert result.created_at.tzinfo is not None
+
+    # Test that writing the same LMP again doesn't create a duplicate
+    sql_store.write_lmp(
+        lmp_id=lmp_id,
+        name=name,
+        source=source,
+        dependencies=dependencies,
+        is_lmp=is_lmp,
+        lm_kwargs=lm_kwargs,
+        version_number=version_number,
+        uses=uses,
+        global_vars=global_vars,
+        free_vars=free_vars,
+        commit_message=commit_message,
+        created_at=created_at
+    )
+
+    with Session(sql_store.engine) as session:
+        count = session.query(SerializedLMP).where(SerializedLMP.lmp_id == lmp_id).count()
+        assert count == 1