diff --git a/buildscripts/bazel_rules_mongo/codeowners/codeowners_generate.py b/buildscripts/bazel_rules_mongo/codeowners/codeowners_generate.py
index ee10d304c37..238f558c751 100644
--- a/buildscripts/bazel_rules_mongo/codeowners/codeowners_generate.py
+++ b/buildscripts/bazel_rules_mongo/codeowners/codeowners_generate.py
@@ -63,7 +63,7 @@ def process_owners_file(output_lines: list[str], node: FileNode) -> None:
     print(f"parsing: {owners_file_path}")
     output_lines.append(f"# The following patterns are parsed from {owners_file_path}")
 
-    with open(owners_file_path, "r") as file:
+    with open(owners_file_path, "r", encoding="utf8") as file:
         contents = yaml.safe_load(file)
         assert "version" in contents, f"Version not found in {owners_file_path}"
         assert contents["version"] in parsers, f"Unsupported version in {owners_file_path}"
@@ -279,7 +279,7 @@ def get_allowed_unowned_files() -> Set[str]:
 
     unowned_files = set()
 
-    with open(allowed_unowned_file_path, "r") as file:
+    with open(allowed_unowned_file_path, "r", encoding="utf8") as file:
         contents = yaml.safe_load(file)
 
         try:
diff --git a/buildscripts/bazel_rules_mongo/codeowners/parsers/owners_v1.py b/buildscripts/bazel_rules_mongo/codeowners/parsers/owners_v1.py
index 9fe3e439174..8c98e18ebdf 100644
--- a/buildscripts/bazel_rules_mongo/codeowners/parsers/owners_v1.py
+++ b/buildscripts/bazel_rules_mongo/codeowners/parsers/owners_v1.py
@@ -83,7 +83,7 @@ class OwnersParserV1:
         if not os.path.exists(parsed_path):
             raise RuntimeError(f"Could not find alias file {path}")
 
-        with open(parsed_path, "r") as file:
+        with open(parsed_path, "r", encoding="utf8") as file:
             contents = yaml.safe_load(file)
             assert "version" in contents, f"Version not found in {path}"
             assert "aliases" in contents, f"Alias not found in {path}"
diff --git a/buildscripts/bazel_rules_mongo/utils/evergreen_git.py b/buildscripts/bazel_rules_mongo/utils/evergreen_git.py
index 0ed144572c5..6a1483e2cd5 100644
--- a/buildscripts/bazel_rules_mongo/utils/evergreen_git.py
+++ b/buildscripts/bazel_rules_mongo/utils/evergreen_git.py
@@ -14,7 +14,7 @@ def get_expansions(expansions_file: str) -> Dict[str, any]:
     if not os.path.exists(expansions_file):
         raise RuntimeError(f"Expansions file not found at {expansions_file}")
 
-    with open(expansions_file, "r") as file:
+    with open(expansions_file, "r", encoding="utf8") as file:
         return yaml.safe_load(file)
 
 
diff --git a/buildscripts/ciconfig/evergreen.py b/buildscripts/ciconfig/evergreen.py
index e7423cf2f4b..b624671b9ae 100644
--- a/buildscripts/ciconfig/evergreen.py
+++ b/buildscripts/ciconfig/evergreen.py
@@ -73,7 +73,7 @@ def parse_evergreen_file(path, evergreen_binary="evergreen"):
     if evergreen_binary:
         # Call 'evergreen evaluate path' to pre-process the project configuration file.
         cmd = [evergreen_binary, "evaluate", path]
-        result = subprocess.run(cmd, capture_output=True, text=True)
+        result = subprocess.run(cmd, capture_output=True, encoding="utf8", text=True)
         if result.returncode:
             raise RuntimeError(
                 "Unable to evaluate {}.\nSTDOUT:{}\nSTDERR:{}".format(
@@ -82,7 +82,7 @@ def parse_evergreen_file(path, evergreen_binary="evergreen"):
             )
         config = yaml.safe_load(result.stdout)
     else:
-        with open(path, "r") as fstream:
+        with open(path, "r", encoding="utf8") as fstream:
             config = yaml.safe_load(fstream)
 
     return EvergreenProjectConfig(config)
diff --git a/buildscripts/evergreen_expansions2bash.py b/buildscripts/evergreen_expansions2bash.py
index 4add23e951d..5f8a203646c 100644
--- a/buildscripts/evergreen_expansions2bash.py
+++ b/buildscripts/evergreen_expansions2bash.py
@@ -20,7 +20,7 @@ except ModuleNotFoundError:
 
 
 def _load_defaults(defaults_file: str) -> dict:
-    with open(defaults_file) as fh:
+    with open(defaults_file, encoding="utf8") as fh:
         defaults = yaml.safe_load(fh)
         if not isinstance(defaults, dict):
             _error(
@@ -67,7 +67,7 @@ def _load_defaults(defaults_file: str) -> dict:
 
 
 def _load_expansions(expansions_file) -> dict:
-    with open(expansions_file) as fh:
+    with open(expansions_file, encoding="utf8") as fh:
         expansions = yaml.safe_load(fh)
 
         if not isinstance(expansions, dict):
diff --git a/buildscripts/evergreen_task_timeout.py b/buildscripts/evergreen_task_timeout.py
index 874624de5f6..6de02627c08 100755
--- a/buildscripts/evergreen_task_timeout.py
+++ b/buildscripts/evergreen_task_timeout.py
@@ -99,7 +99,7 @@ class TimeoutOverrides(BaseModel):
     @classmethod
     def from_yaml_file(cls, file_path: Path) -> "TimeoutOverrides":
         """Read the timeout overrides from the given file."""
-        with open(file_path) as file_handler:
+        with open(file_path, encoding="utf8") as file_handler:
             return cls(**yaml.safe_load(file_handler))
 
     def _lookup_override(self, build_variant: str, task_name: str) -> Optional[TimeoutOverride]:
@@ -173,7 +173,7 @@ def output_timeout(
         output["timeout_secs"] = math.ceil(idle_timeout.total_seconds())
 
     if output_file:
-        with open(output_file, "w") as outfile:
+        with open(output_file, "w", encoding="utf8") as outfile:
             yaml.dump(output, stream=outfile, default_flow_style=False)
 
     yaml.dump(output, stream=sys.stdout, default_flow_style=False)
diff --git a/buildscripts/idl/gen_all_feature_flag_list.py b/buildscripts/idl/gen_all_feature_flag_list.py
index 45ddc54c0b3..60f002ade74 100755
--- a/buildscripts/idl/gen_all_feature_flag_list.py
+++ b/buildscripts/idl/gen_all_feature_flag_list.py
@@ -87,7 +87,9 @@ def get_all_feature_flags_turned_off_by_default(idl_dirs: List[str] = None):
         if not binder.is_feature_flag_enabled_by_default(flag)
     ]
 
-    with open("buildscripts/resmokeconfig/fully_disabled_feature_flags.yml") as fully_disabled_ffs:
+    with open(
+        "buildscripts/resmokeconfig/fully_disabled_feature_flags.yml", encoding="utf8"
+    ) as fully_disabled_ffs:
         force_disabled_flags = yaml.safe_load(fully_disabled_ffs)
 
     return list(set(all_default_false_flags) - set(force_disabled_flags))
diff --git a/buildscripts/idl/idl_check_compatibility.py b/buildscripts/idl/idl_check_compatibility.py
index 15508dc0ea5..c779e961987 100644
--- a/buildscripts/idl/idl_check_compatibility.py
+++ b/buildscripts/idl/idl_check_compatibility.py
@@ -62,7 +62,7 @@ def load_rules_file() -> dict:
     if not os.path.exists(abs_filename):
         raise ValueError(f"Rules file {abs_filename} not found")
 
-    with open(abs_filename) as file:
+    with open(abs_filename, encoding="utf8") as file:
         return yaml.safe_load(file)
 
 
diff --git a/buildscripts/idl/tests/test_yaml_schema.py b/buildscripts/idl/tests/test_yaml_schema.py
index 270a3767ae1..1cc363f81bb 100755
--- a/buildscripts/idl/tests/test_yaml_schema.py
+++ b/buildscripts/idl/tests/test_yaml_schema.py
@@ -79,7 +79,7 @@ class TestJSONSchema(testcase.IDLTestcase):
         return os.path.join(self._base_dir, "buildscripts", "idl")
 
     def load_yaml_file(self, file_path):
-        with open(file_path, "r") as f:
+        with open(file_path, "r", encoding="utf8") as f:
             return yaml.safe_load(f)
 
     def validate_yaml_file(self, file_path, schema):
diff --git a/buildscripts/monitor_build_status/code_lockdown_config.py b/buildscripts/monitor_build_status/code_lockdown_config.py
index f17b6cb5e47..07511dc1ba8 100644
--- a/buildscripts/monitor_build_status/code_lockdown_config.py
+++ b/buildscripts/monitor_build_status/code_lockdown_config.py
@@ -53,7 +53,7 @@ class CodeLockdownConfig(BaseModel):
         :param file_path: Path to file.
         :return: Config object.
         """
-        with open(file_path) as file_handler:
+        with open(file_path, encoding="utf8") as file_handler:
             return cls(**yaml.safe_load(file_handler))
 
     def get_all_group_names(self) -> List[str]:
diff --git a/buildscripts/resmokelib/configure_resmoke.py b/buildscripts/resmokelib/configure_resmoke.py
index a6711edd10f..7b1d3cd6dd0 100644
--- a/buildscripts/resmokelib/configure_resmoke.py
+++ b/buildscripts/resmokelib/configure_resmoke.py
@@ -438,7 +438,7 @@ flags in common: {common_set}
     )
     if not _config.INCLUDE_FULLY_DISABLED_FEATURE_TESTS:
         with open(
-            "buildscripts/resmokeconfig/fully_disabled_feature_flags.yml"
+            "buildscripts/resmokeconfig/fully_disabled_feature_flags.yml", encoding="utf8"
         ) as fully_disabled_ffs:
             # the ENABLED_FEATURE_FLAGS list already excludes the fully disabled features flags
             # This keeps any feature flags enabled that were manually turned on from being excluded
diff --git a/buildscripts/resmokelib/multiversion/multiversion_service.py b/buildscripts/resmokelib/multiversion/multiversion_service.py
index 75f237feeac..f01bb231b9d 100644
--- a/buildscripts/resmokelib/multiversion/multiversion_service.py
+++ b/buildscripts/resmokelib/multiversion/multiversion_service.py
@@ -124,7 +124,7 @@ class MongoVersion(BaseModel):
         :param yaml_file: Path to yaml file.
         :return: MongoVersion read from file.
         """
-        mongo_version_yml_file = open(yaml_file, "r")
+        mongo_version_yml_file = open(yaml_file, "r", encoding="utf8")
         return cls(**yaml.safe_load(mongo_version_yml_file))
 
     def get_version(self) -> Version:
@@ -164,7 +164,7 @@ class MongoReleases(BaseModel):
         :return: MongoReleases read from file.
         """
 
-        with open(yaml_file, "r") as mongo_releases_file:
+        with open(yaml_file, "r", encoding="utf8") as mongo_releases_file:
             yaml_contents = mongo_releases_file.read()
         safe_load_result = yaml.safe_load(yaml_contents)
         try:
diff --git a/buildscripts/resmokelib/powercycle/powercycle.py b/buildscripts/resmokelib/powercycle/powercycle.py
index b14298da68e..9c9ee8a6432 100755
--- a/buildscripts/resmokelib/powercycle/powercycle.py
+++ b/buildscripts/resmokelib/powercycle/powercycle.py
@@ -1317,10 +1317,10 @@ def new_resmoke_config(config_file, new_config_file, test_data, eval_str=""):
             "config": {"shell_options": {"eval": eval_str, "global_vars": {"TestData": test_data}}}
         }
     }
-    with open(config_file, "r") as yaml_stream:
+    with open(config_file, "r", encoding="utf8") as yaml_stream:
         config = yaml.safe_load(yaml_stream)
     config.update(new_config)
-    with open(new_config_file, "w") as yaml_stream:
+    with open(new_config_file, "w", encoding="utf8") as yaml_stream:
         yaml.safe_dump(config, yaml_stream)
 
 
diff --git a/buildscripts/resmokelib/powercycle/powercycle_config.py b/buildscripts/resmokelib/powercycle/powercycle_config.py
index ed5dcb6e377..31197600ffd 100644
--- a/buildscripts/resmokelib/powercycle/powercycle_config.py
+++ b/buildscripts/resmokelib/powercycle/powercycle_config.py
@@ -43,7 +43,7 @@ def get_task_config(task_name, is_remote):
     else:
         config_location = powercycle.abs_path(POWERCYCLE_TASKS_CONFIG)
 
-    with open(config_location) as file_handle:
+    with open(config_location, encoding="utf8") as file_handle:
         raw_yaml = yaml.safe_load(file_handle)
     tasks_raw_yaml = raw_yaml.get("tasks", [])
 
diff --git a/buildscripts/resmokelib/setup_multiversion/setup_multiversion.py b/buildscripts/resmokelib/setup_multiversion/setup_multiversion.py
index 3bdace3b79b..36c865cf5bf 100644
--- a/buildscripts/resmokelib/setup_multiversion/setup_multiversion.py
+++ b/buildscripts/resmokelib/setup_multiversion/setup_multiversion.py
@@ -124,7 +124,7 @@ class SetupMultiversion(Subcommand):
         self.github_oauth_token = (
             github_oauth_token.replace("token ", "") if github_oauth_token else None
         )
-        with open(config.SETUP_MULTIVERSION_CONFIG) as file_handle:
+        with open(config.SETUP_MULTIVERSION_CONFIG, encoding="utf8") as file_handle:
             raw_yaml = yaml.safe_load(file_handle)
         self.config = config.SetupMultiversionConfig(raw_yaml)
 
diff --git a/buildscripts/resmokelib/suitesconfig.py b/buildscripts/resmokelib/suitesconfig.py
index 8f1bdf66921..baf6d16f658 100644
--- a/buildscripts/resmokelib/suitesconfig.py
+++ b/buildscripts/resmokelib/suitesconfig.py
@@ -329,7 +329,7 @@ class MatrixSuiteConfig(SuiteConfigInterface):
         new_text = cls.generate_matrix_suite_text(suite_name)
         new_yaml = yaml.safe_load(new_text)
 
-        with open(generated_path, "r") as file:
+        with open(generated_path, "r", encoding="utf8") as file:
             old_text = file.read()
             old_yaml = yaml.safe_load(old_text)
             if new_yaml != old_yaml:
diff --git a/buildscripts/resmokelib/testing/hooks/generate_and_check_perf_results.py b/buildscripts/resmokelib/testing/hooks/generate_and_check_perf_results.py
index 3a05b9dc27b..fcdc4d0dc41 100644
--- a/buildscripts/resmokelib/testing/hooks/generate_and_check_perf_results.py
+++ b/buildscripts/resmokelib/testing/hooks/generate_and_check_perf_results.py
@@ -164,7 +164,7 @@ class GenerateAndCheckPerfResults(interface.Hook):
         self.create_time = datetime.datetime.now()
 
         try:
-            with open(THRESHOLD_LOCATION) as fh:
+            with open(THRESHOLD_LOCATION, encoding="utf8") as fh:
                 self.performance_thresholds = yaml.safe_load(fh)["tests"]
         except Exception:
             self.logger.exception(
diff --git a/buildscripts/resmokelib/testing/tags.py b/buildscripts/resmokelib/testing/tags.py
index 5ab8d6cb450..064d7ac6ce9 100644
--- a/buildscripts/resmokelib/testing/tags.py
+++ b/buildscripts/resmokelib/testing/tags.py
@@ -42,7 +42,7 @@ class TagsConfig(object):
         See TagsConfig.__init__() for the keyword arguments that can be specified.
         """
 
-        with open(filename, "r") as fstream:
+        with open(filename, "r", encoding="utf8") as fstream:
             raw = yaml.safe_load(fstream)
 
         return cls(raw, **kwargs)
diff --git a/buildscripts/resmokelib/utils/__init__.py b/buildscripts/resmokelib/utils/__init__.py
index ef8ab87d6e5..6face1cb89a 100644
--- a/buildscripts/resmokelib/utils/__init__.py
+++ b/buildscripts/resmokelib/utils/__init__.py
@@ -56,7 +56,7 @@ def is_string_list(lst):
 def load_yaml_file(filename):
     """Attempt to read 'filename' as YAML."""
     try:
-        with open(filename, "r") as fp:
+        with open(filename, "r", encoding="utf8") as fp:
             return yaml.safe_load(fp)
     except yaml.YAMLError as err:
         raise ValueError("File '%s' contained invalid YAML: %s" % (filename, err))
diff --git a/buildscripts/tests/resmoke_end2end/test_resmoke.py b/buildscripts/tests/resmoke_end2end/test_resmoke.py
index 5e0d6d40805..733a23db74a 100644
--- a/buildscripts/tests/resmoke_end2end/test_resmoke.py
+++ b/buildscripts/tests/resmoke_end2end/test_resmoke.py
@@ -403,7 +403,7 @@ class TestSetParameters(_ResmokeSelftest):
     def generate_suite(self, suite_output_path, template_file):
         """Read the template file, substitute the `outputLocation` and rewrite to the file `suite_output_path`."""
 
-        with open(os.path.normpath(template_file), "r") as template_suite_fd:
+        with open(os.path.normpath(template_file), "r", encoding="utf8") as template_suite_fd:
             suite = yaml.safe_load(template_suite_fd)
 
         try:
@@ -568,7 +568,7 @@ class TestDiscovery(_ResmokeSelftest):
         )
 
         with open(
-            "buildscripts/resmokeconfig/fully_disabled_feature_flags.yml"
+            "buildscripts/resmokeconfig/fully_disabled_feature_flags.yml", encoding="utf8"
         ) as fully_disabled_ffs:
             self.assertIn(
                 "featureFlagFryer",
@@ -832,7 +832,7 @@ class TestMultiversionConfig(unittest.TestCase):
             ],
             check=True,
         )
-        with open(file_name, "r") as file:
+        with open(file_name, "r", encoding="utf8") as file:
             file_contents = file.read()
 
         try:
diff --git a/buildscripts/tests/resmoke_validation/test_matrix_suite_generation.py b/buildscripts/tests/resmoke_validation/test_matrix_suite_generation.py
index 4cfd14ada29..914159c9b7b 100644
--- a/buildscripts/tests/resmoke_validation/test_matrix_suite_generation.py
+++ b/buildscripts/tests/resmoke_validation/test_matrix_suite_generation.py
@@ -42,7 +42,7 @@ class TestSuiteGeneration(unittest.TestCase):
         tested_suite = "test_matrix_suite"
         generated_suite_path = self.matrix_suite_config.get_generated_suite_path(tested_suite)
         self.matrix_suite_config.generate_matrix_suite_file(tested_suite)
-        with open(generated_suite_path, "r+") as file:
+        with open(generated_suite_path, "r+", encoding="utf8") as file:
             gen_yaml = yaml.safe_load(file)
             gen_yaml["abc"] = "def"
             file.seek(0)
diff --git a/buildscripts/util/codeowners_utils.py b/buildscripts/util/codeowners_utils.py
index 86d2b7a7bc5..46ddbf2d4ba 100644
--- a/buildscripts/util/codeowners_utils.py
+++ b/buildscripts/util/codeowners_utils.py
@@ -16,7 +16,7 @@ def process_owners(cur_dir: str) -> Tuple[Dict[re.Pattern, List[str]], bool]:
     if not os.path.exists(owners_file_path):
         return process_owners(os.path.dirname(cur_dir))
 
-    with open(owners_file_path, "r") as f:
+    with open(owners_file_path, "r", encoding="utf8") as f:
         contents = yaml.safe_load(f)
 
         assert "version" in contents, f"Version not found in {owners_file_path}"
@@ -50,7 +50,9 @@ def process_owners(cur_dir: str) -> Tuple[Dict[re.Pattern, List[str]], bool]:
 
 class Owners:
     def __init__(self):
-        self.co_jira_map = yaml.safe_load(open("buildscripts/util/co_jira_map.yml", "r"))
+        self.co_jira_map = yaml.safe_load(
+            open("buildscripts/util/co_jira_map.yml", "r", encoding="utf8")
+        )
 
     def get_codeowners(self, file_path: str) -> List[str]:
         cur_dir = os.path.dirname(file_path)
diff --git a/buildscripts/util/expansions.py b/buildscripts/util/expansions.py
index c98ddcac4ee..ae418768f7b 100644
--- a/buildscripts/util/expansions.py
+++ b/buildscripts/util/expansions.py
@@ -16,7 +16,7 @@ def get_expansions() -> dict:
     if not os.path.exists(expansions_file):
         return None
 
-    with open(expansions_file, "r") as file:
+    with open(expansions_file, "r", encoding="utf8") as file:
         return yaml.safe_load(file)
 
 
diff --git a/buildscripts/util/fileops.py b/buildscripts/util/fileops.py
index 0c765adac8b..4b9f7292368 100644
--- a/buildscripts/util/fileops.py
+++ b/buildscripts/util/fileops.py
@@ -70,5 +70,5 @@ def read_yaml_file(path: str) -> Dict[str, Any]:
     :param path: Path to file to read.
     :return: Contents of given file.
     """
-    with open(path) as file_handle:
+    with open(path, encoding="utf8") as file_handle:
         return yaml.safe_load(file_handle)
diff --git a/buildscripts/util/generate_co_jira_map.py b/buildscripts/util/generate_co_jira_map.py
index 333fe48cff8..7262d967f35 100644
--- a/buildscripts/util/generate_co_jira_map.py
+++ b/buildscripts/util/generate_co_jira_map.py
@@ -7,7 +7,7 @@ if __name__ == "__main__":
     owners_paths = glob.glob("**/OWNERS.yml", recursive=True)
     print(len(owners_paths))
     for path in owners_paths:
-        with open(path, "r") as owner_file:
+        with open(path, "r", encoding="utf8") as owner_file:
             contents = yaml.safe_load(owner_file)
             if "filters" not in contents:
                 continue
@@ -15,5 +15,5 @@ if __name__ == "__main__":
                 assert "approvers" in file_filter
                 approvers.update(set(file_filter["approvers"]))
 
-    f = open("co_jira_map.yml", "w+")
+    f = open("co_jira_map.yml", "w+", encoding="utf8")
     yaml.dump({approver: "jira_team" for approver in approvers}, f)
diff --git a/buildscripts/util/read_config.py b/buildscripts/util/read_config.py
index 26fc19cecdc..b8a21b73807 100644
--- a/buildscripts/util/read_config.py
+++ b/buildscripts/util/read_config.py
@@ -39,7 +39,7 @@ def read_config_file(config_file):
     """
     config_file_data = {}
     if config_file:
-        with open(config_file) as file_handle:
+        with open(config_file, encoding="utf8") as file_handle:
             config_file_data = yaml.safe_load(file_handle)
 
     return config_file_data
diff --git a/buildscripts/validate_mongocryptd.py b/buildscripts/validate_mongocryptd.py
index fd73104b932..283b73766ee 100644
--- a/buildscripts/validate_mongocryptd.py
+++ b/buildscripts/validate_mongocryptd.py
@@ -75,7 +75,7 @@ def read_variable_from_yml(filename, variable_name):
     :param variable_name: Variable to read from file.
     :return: Value of variable or None.
     """
-    with open(filename, "r") as fh:
+    with open(filename, "r", encoding="utf8") as fh:
         nodes = yaml.safe_load(fh)
 
     variables = nodes["variables"]
diff --git a/buildscripts/yaml_key_value.py b/buildscripts/yaml_key_value.py
index 98e4a634ea3..c9336a235e3 100755
--- a/buildscripts/yaml_key_value.py
+++ b/buildscripts/yaml_key_value.py
@@ -8,7 +8,7 @@ import yaml
 
 def get_yaml_value(yaml_file, yaml_key):
     """Return string value for 'yaml_key' from 'yaml_file'."""
-    with open(yaml_file, "r") as ystream:
+    with open(yaml_file, "r", encoding="utf8") as ystream:
         yaml_dict = yaml.safe_load(ystream)
     return str(yaml_dict.get(yaml_key, ""))
 
diff --git a/evergreen/generate_override_timeout.py b/evergreen/generate_override_timeout.py
index 1afd84ea9ef..c05c00d6d46 100644
--- a/evergreen/generate_override_timeout.py
+++ b/evergreen/generate_override_timeout.py
@@ -8,12 +8,12 @@ parser.add_argument("--variant_name")
 parser.add_argument("--task_name")
 args = parser.parse_args()
 
-with open("etc/evergreen_yml_components/configuration.yml") as f:
+with open("etc/evergreen_yml_components/configuration.yml", encoding="utf8") as f:
     yml = yaml.safe_load(f)
     default_timeout = yml["exec_timeout_secs"]
 
 override_timeout = None
-with open("etc/evergreen_timeouts.yml") as f:
+with open("etc/evergreen_timeouts.yml", encoding="utf8") as f:
     yml = yaml.safe_load(f)
     if args.variant_name in yml["overrides"]:
         for task in yml["overrides"][args.variant_name]:
@@ -21,7 +21,7 @@ with open("etc/evergreen_timeouts.yml") as f:
                 override_timeout = task["exec_timeout"] * 60
                 break
 
-with open("override_task_timeout.yml", "w") as f:
+with open("override_task_timeout.yml", "w", encoding="utf8") as f:
     if override_timeout:
         print(
             f"Overriding timeout for {args.variant_name}:{args.task_name} of {override_timeout} seconds."