diff --git a/conda_lock/conda_lock.py b/conda_lock/conda_lock.py
index e7b0689d3..d8bd1350e 100644
--- a/conda_lock/conda_lock.py
+++ b/conda_lock/conda_lock.py
@@ -523,7 +523,9 @@ def do_render(
                     "dev-dependencies": str(include_dev_dependencies).lower(),
                     "input-hash": lockfile.metadata.content_hash,
                     "version": distribution("conda_lock").version,
-                    "timestamp": datetime.datetime.utcnow().strftime("%Y%m%dT%H%M%SZ"),
+                    "timestamp": datetime.datetime.now(datetime.timezone.utc).strftime(
+                        "%Y%m%dT%H%M%SZ"
+                    ),
                 }
 
                 filename = filename_template.format(**context)
diff --git a/conda_lock/lockfile/__init__.py b/conda_lock/lockfile/__init__.py
index 92c0cddef..edf0a2bb3 100644
--- a/conda_lock/lockfile/__init__.py
+++ b/conda_lock/lockfile/__init__.py
@@ -178,9 +178,9 @@ def parse_conda_lock_file(path: pathlib.Path) -> Lockfile:
         content = yaml.safe_load(f)
     version = content.pop("version", None)
     if version == 1:
-        lockfile = lockfile_v1_to_v2(LockfileV1.parse_obj(content))
+        lockfile = lockfile_v1_to_v2(LockfileV1.model_validate(content))
     elif version == 2:
-        lockfile = Lockfile.parse_obj(content)
+        lockfile = Lockfile.model_validate(content)
     elif version is None:
         raise MissingLockfileVersion(f"{path} is missing a version")
     else:
diff --git a/conda_lock/lockfile/v1/models.py b/conda_lock/lockfile/v1/models.py
index 05706f171..919ea5944 100644
--- a/conda_lock/lockfile/v1/models.py
+++ b/conda_lock/lockfile/v1/models.py
@@ -89,7 +89,9 @@ class TimeMeta(StrictModel):
     @classmethod
     def create(cls) -> "TimeMeta":
         return cls(
-            created_at=datetime.datetime.utcnow().isoformat(timespec="seconds") + "Z"
+            created_at=datetime.datetime.now(datetime.timezone.utc).strftime(
+                "%Y-%m-%dT%H:%M:%SZ"
+            )
         )
 
 
diff --git a/conda_lock/pypi_solver.py b/conda_lock/pypi_solver.py
index 444ae0650..4c3ebed44 100644
--- a/conda_lock/pypi_solver.py
+++ b/conda_lock/pypi_solver.py
@@ -437,10 +437,8 @@ def _get_url(link: Link) -> str:
 
 def _compute_hash(link: Link, lock_spec_hash: Optional[str]) -> HashModel:
     if lock_spec_hash is None:
-        hashes: Dict[str, str] = {}
-        if link.hash_name is not None and link.hash is not None:
-            hashes[link.hash_name] = link.hash
-        return HashModel.parse_obj(hashes)
+        hashes: Dict[str, str] = dict(link.hashes)
+        return HashModel.model_validate(hashes)
     else:
         # A hash was provided in the lock spec, so that takes precedence
         algo, value = lock_spec_hash.split(":")
diff --git a/conda_lock/virtual_package.py b/conda_lock/virtual_package.py
index 7f372da8b..4732e3a01 100644
--- a/conda_lock/virtual_package.py
+++ b/conda_lock/virtual_package.py
@@ -257,7 +257,7 @@ def virtual_package_repo_from_specification(
         data = yaml.safe_load(fp)
     logging.debug("Virtual package spec: %s", data)
 
-    spec = VirtualPackageSpec.parse_obj(data)
+    spec = VirtualPackageSpec.model_validate(data)
 
     repodata = _init_fake_repodata()
     for subdir, subdir_spec in spec.subdirs.items():
diff --git a/pyproject.toml b/pyproject.toml
index cbd8b9467..b515f09b8 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -122,10 +122,8 @@ addopts = [
     "--ignore-glob=**/vendor_poetry/**",
     "--ignore-glob=**/_vendor/**"
 ]
+log_level = "DEBUG"
 testpaths = ["tests", "conda_lock"]
-flake8-max-line-length = 105
-flake8-ignore = ["docs/* ALL", "conda_lock/_version.py ALL"]
-filterwarnings = "ignore::DeprecationWarning"
 
 [tool.vendoring]
 destination = "conda_lock/_vendor"
diff --git a/tests/test_conda_lock.py b/tests/test_conda_lock.py
index 92e7ec7da..6f32ac3bf 100644
--- a/tests/test_conda_lock.py
+++ b/tests/test_conda_lock.py
@@ -1267,7 +1267,7 @@ def test_run_lock_with_time_metadata(
     if is_micromamba(conda_exe):
         monkeypatch.setenv("CONDA_FLAGS", "-v")
     frozen_datetime = datetime.datetime(
-        year=1, month=7, day=12, hour=15, minute=6, second=3
+        year=1971, month=7, day=12, hour=15, minute=6, second=3
     )
     with freeze_time(frozen_datetime):
         run_lock(