diff --git a/safir-arq/src/safir/arq/_models.py b/safir-arq/src/safir/arq/_models.py
index 4b5e6f5b..eb94bcff 100644
--- a/safir-arq/src/safir/arq/_models.py
+++ b/safir-arq/src/safir/arq/_models.py
@@ -4,7 +4,7 @@
 
 from dataclasses import dataclass
 from datetime import datetime
-from enum import Enum
+from enum import StrEnum
 from typing import Any, Self
 
 from arq.jobs import Job, JobStatus
@@ -18,7 +18,7 @@
 ]
 
 
-class ArqMode(str, Enum):
+class ArqMode(StrEnum):
     """Mode configuration for the Arq queue."""
 
     production = "production"
diff --git a/safir/src/safir/github/models.py b/safir/src/safir/github/models.py
index 54a43014..51d00557 100644
--- a/safir/src/safir/github/models.py
+++ b/safir/src/safir/github/models.py
@@ -3,7 +3,7 @@
 from __future__ import annotations
 
 from base64 import b64decode
-from enum import Enum
+from enum import StrEnum
 
 from pydantic import BaseModel, Field, HttpUrl
 
@@ -128,7 +128,7 @@ class GitHubRepositoryModel(BaseModel):
     )
 
 
-class GitHubPullState(str, Enum):
+class GitHubPullState(StrEnum):
     """The state of a GitHub pull request (PR).
 
     https://docs.github.com/en/rest/pulls/pulls#get-a-pull-request
@@ -227,7 +227,7 @@ def decode(self) -> str:
             )
 
 
-class GitHubCheckSuiteStatus(str, Enum):
+class GitHubCheckSuiteStatus(StrEnum):
     """The status of a GitHub check suite."""
 
     queued = "queued"
@@ -240,7 +240,7 @@ class GitHubCheckSuiteStatus(str, Enum):
     """The check suite has completed."""
 
 
-class GitHubCheckSuiteConclusion(str, Enum):
+class GitHubCheckSuiteConclusion(StrEnum):
     """The conclusion state of a GitHub check suite."""
 
     success = "success"
@@ -301,7 +301,7 @@ class GitHubCheckSuiteModel(BaseModel):
     )
 
 
-class GitHubCheckRunStatus(str, Enum):
+class GitHubCheckRunStatus(StrEnum):
     """The check run status."""
 
     queued = "queued"
@@ -314,7 +314,7 @@ class GitHubCheckRunStatus(str, Enum):
     """The check run has completed."""
 
 
-class GitHubCheckRunConclusion(str, Enum):
+class GitHubCheckRunConclusion(StrEnum):
     """The check run conclusion state."""
 
     success = "success"
@@ -341,7 +341,7 @@ class GitHubCheckRunConclusion(str, Enum):
     """The check run is stale."""
 
 
-class GitHubCheckRunAnnotationLevel(str, Enum):
+class GitHubCheckRunAnnotationLevel(StrEnum):
     """The level of a check run output annotation."""
 
     notice = "notice"
diff --git a/safir/src/safir/models/_errors.py b/safir/src/safir/models/_errors.py
index 9993f5d9..63fcc542 100644
--- a/safir/src/safir/models/_errors.py
+++ b/safir/src/safir/models/_errors.py
@@ -1,6 +1,6 @@
 """Error models for FastAPI applications."""
 
-from enum import Enum
+from enum import StrEnum
 
 from pydantic import BaseModel, Field
 
@@ -11,7 +11,7 @@
 ]
 
 
-class ErrorLocation(str, Enum):
+class ErrorLocation(StrEnum):
     """Possible locations for an error.
 
     The first element of ``loc`` in `ErrorDetail` should be chosen from one of