diff --git a/src/pyproject.toml b/src/pyproject.toml
index 228f148..6278222 100644
--- a/src/pyproject.toml
+++ b/src/pyproject.toml
@@ -13,8 +13,8 @@ dependencies = [
     "httptools",
     # Used by uvicorn for reload functionality
     "watchfiles",
-    "azure-ai-inference",
     "azure-identity",
+    "openai",
     "aiohttp",
     "python-dotenv",
     "pyyaml"
diff --git a/src/quartapp/chat.py b/src/quartapp/chat.py
index 6e3dd3c..bb2d62e 100644
--- a/src/quartapp/chat.py
+++ b/src/quartapp/chat.py
@@ -1,13 +1,8 @@
 import json
 import os
 
-from azure.ai.inference.aio import ChatCompletionsClient
-from azure.ai.inference.models import SystemMessage
-from azure.identity.aio import (
-    AzureDeveloperCliCredential,
-    ChainedTokenCredential,
-    ManagedIdentityCredential,
-)
+from azure.identity.aio import AzureDeveloperCliCredential, ManagedIdentityCredential, get_bearer_token_provider
+from openai import AsyncOpenAI
 from quart import (
     Blueprint,
     Response,
@@ -22,38 +17,34 @@
 
 @bp.before_app_serving
 async def configure_openai():
-    # Use ManagedIdentityCredential with the client_id for user-assigned managed identities
-    user_assigned_managed_identity_credential = ManagedIdentityCredential(client_id=os.getenv("AZURE_CLIENT_ID"))
-
-    # Use AzureDeveloperCliCredential with the current tenant.
-    azure_dev_cli_credential = AzureDeveloperCliCredential(tenant_id=os.getenv("AZURE_TENANT_ID"), process_timeout=60)
-
-    # Create a ChainedTokenCredential with ManagedIdentityCredential and AzureDeveloperCliCredential
-    #  - ManagedIdentityCredential is used for deployment on Azure Container Apps
-
-    #  - AzureDeveloperCliCredential is used for local development
-    # The order of the credentials is important, as the first valid token is used
-    # For more information check out:
-
-    # https://learn.microsoft.com/azure/developer/python/sdk/authentication/credential-chains?tabs=ctc#chainedtokencredential-overview
-    azure_credential = ChainedTokenCredential(user_assigned_managed_identity_credential, azure_dev_cli_credential)
-    current_app.logger.info("Using Azure OpenAI with credential")
-
-    if not os.getenv("AZURE_INFERENCE_ENDPOINT"):
-        raise ValueError("AZURE_INFERENCE_ENDPOINT is required for Azure OpenAI")
+    if os.getenv("RUNNING_IN_PRODUCTION"):
+        client_id = os.environ["AZURE_CLIENT_ID"]
+        current_app.logger.info("Using Azure OpenAI with managed identity credential for client ID: %s", client_id)
+        bp.azure_credential = ManagedIdentityCredential(client_id=client_id)
+    else:
+        tenant_id = os.environ["AZURE_TENANT_ID"]
+        current_app.logger.info("Using Azure OpenAI with Azure Developer CLI credential for tenant ID: %s", tenant_id)
+        bp.azure_credential = AzureDeveloperCliCredential(tenant_id=tenant_id)
+
+    # Get the token provider for Azure OpenAI based on the selected Azure credential
+    bp.openai_token_provider = get_bearer_token_provider(
+        bp.azure_credential, "https://cognitiveservices.azure.com/.default"
+    )
 
     # Create the Asynchronous Azure OpenAI client
-    bp.ai_client = ChatCompletionsClient(
-        endpoint=os.environ["AZURE_INFERENCE_ENDPOINT"],
-        credential=azure_credential,
-        credential_scopes=["https://cognitiveservices.azure.com/.default"],
-        model="DeepSeek-R1",
+    bp.openai_client = AsyncOpenAI(
+        base_url=os.environ["AZURE_INFERENCE_ENDPOINT"],
+        api_key=await bp.openai_token_provider(),
+        default_query={"api-version": "2024-05-01-preview"},
     )
 
+    # Set the model name to the Azure OpenAI model deployment name
+    bp.openai_model = os.getenv("AZURE_DEEPSEEK_DEPLOYMENT")
+
 
 @bp.after_app_serving
 async def shutdown_openai():
-    await bp.ai_client.close()
+    await bp.openai_client.close()
 
 
 @bp.get("/")
@@ -69,15 +60,20 @@ async def chat_handler():
     async def response_stream():
         # This sends all messages, so API request may exceed token limits
         all_messages = [
-            SystemMessage(content="You are a helpful assistant."),
+            {"role": "system", "content": "You are a helpful assistant."},
         ] + request_messages
 
-        client: ChatCompletionsClient = bp.ai_client
-        result = await client.complete(messages=all_messages, max_tokens=2048, stream=True)
+        bp.openai_client.api_key = await bp.openai_token_provider()
+        chat_coroutine = bp.openai_client.chat.completions.create(
+            # Azure Open AI takes the deployment name as the model name
+            model=bp.openai_model,
+            messages=all_messages,
+            stream=True,
+        )
 
         try:
             is_thinking = False
-            async for update in result:
+            async for update in await chat_coroutine:
                 if update.choices:
                     content = update.choices[0].delta.content
                     if content == "<think>":
@@ -103,4 +99,4 @@ async def response_stream():
             current_app.logger.error(e)
             yield json.dumps({"error": str(e)}, ensure_ascii=False) + "\n"
 
-    return Response(response_stream(), mimetype="application/json")
+    return Response(response_stream())
diff --git a/src/requirements.txt b/src/requirements.txt
index c358a96..3421755 100644
--- a/src/requirements.txt
+++ b/src/requirements.txt
@@ -1,5 +1,5 @@
 #
-# This file is autogenerated by pip-compile with Python 3.11
+# This file is autogenerated by pip-compile with Python 3.12
 # by the following command:
 #
 #    pip-compile --output-file=requirements.txt pyproject.toml
@@ -12,16 +12,17 @@ aiohttp==3.10.11
     # via quartapp (pyproject.toml)
 aiosignal==1.3.1
     # via aiohttp
+annotated-types==0.7.0
+    # via pydantic
 anyio==4.6.0
-    # via watchfiles
+    # via
+    #   httpx
+    #   openai
+    #   watchfiles
 attrs==24.2.0
     # via aiohttp
-azure-ai-inference==1.0.0b8
-    # via quartapp (pyproject.toml)
 azure-core==1.31.0
-    # via
-    #   azure-ai-inference
-    #   azure-identity
+    # via azure-identity
 azure-identity==1.19.0
     # via quartapp (pyproject.toml)
 blinker==1.8.2
@@ -29,7 +30,10 @@ blinker==1.8.2
     #   flask
     #   quart
 certifi==2024.8.30
-    # via requests
+    # via
+    #   httpcore
+    #   httpx
+    #   requests
 cffi==1.17.1
     # via cryptography
 charset-normalizer==3.4.0
@@ -44,6 +48,8 @@ cryptography==44.0.1
     #   azure-identity
     #   msal
     #   pyjwt
+distro==1.9.0
+    # via openai
 flask==3.0.3
     # via quart
 frozenlist==1.4.1
@@ -54,6 +60,7 @@ gunicorn==23.0.0
     # via quartapp (pyproject.toml)
 h11==0.14.0
     # via
+    #   httpcore
     #   hypercorn
     #   uvicorn
     #   wsproto
@@ -61,8 +68,12 @@ h2==4.1.0
     # via hypercorn
 hpack==4.0.0
     # via h2
+httpcore==1.0.7
+    # via httpx
 httptools==0.6.4
     # via quartapp (pyproject.toml)
+httpx==0.28.1
+    # via openai
 hypercorn==0.17.3
     # via quart
 hyperframe==6.0.1
@@ -70,10 +81,9 @@ hyperframe==6.0.1
 idna==3.10
     # via
     #   anyio
+    #   httpx
     #   requests
     #   yarl
-isodate==0.7.2
-    # via azure-ai-inference
 itsdangerous==2.2.0
     # via
     #   flask
@@ -82,6 +92,8 @@ jinja2==3.1.5
     # via
     #   flask
     #   quart
+jiter==0.9.0
+    # via openai
 markupsafe==3.0.1
     # via
     #   jinja2
@@ -97,6 +109,8 @@ multidict==6.1.0
     # via
     #   aiohttp
     #   yarl
+openai==1.66.2
+    # via quartapp (pyproject.toml)
 packaging==24.1
     # via gunicorn
 portalocker==2.10.1
@@ -107,8 +121,14 @@ propcache==0.2.0
     # via yarl
 pycparser==2.22
     # via cffi
+pydantic==2.10.6
+    # via openai
+pydantic-core==2.27.2
+    # via pydantic
 pyjwt[crypto]==2.9.0
-    # via msal
+    # via
+    #   msal
+    #   pyjwt
 python-dotenv==1.0.1
     # via quartapp (pyproject.toml)
 pyyaml==6.0.2
@@ -122,12 +142,18 @@ requests==2.32.3
 six==1.16.0
     # via azure-core
 sniffio==1.3.1
-    # via anyio
+    # via
+    #   anyio
+    #   openai
+tqdm==4.67.1
+    # via openai
 typing-extensions==4.12.2
     # via
-    #   azure-ai-inference
     #   azure-core
     #   azure-identity
+    #   openai
+    #   pydantic
+    #   pydantic-core
 urllib3==2.2.3
     # via requests
 uvicorn==0.32.0
diff --git a/tests/conftest.py b/tests/conftest.py
index c373604..c5cbac0 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -1,4 +1,4 @@
-import azure.ai.inference.models
+import openai
 import pytest
 import pytest_asyncio
 
@@ -13,54 +13,70 @@ class AsyncChatCompletionIterator:
         def __init__(self, answer: str):
             self.chunk_index = 0
             self.chunks = [
-                azure.ai.inference.models.StreamingChatCompletionsUpdate(
-                    id="test-123",
-                    created=1703462735,
-                    model="DeepSeek-R1",
-                    choices=[
-                        azure.ai.inference.models.StreamingChatChoiceUpdate(
-                            delta=azure.ai.inference.models.StreamingChatResponseMessageUpdate(
-                                content=None, role="assistant"
-                            ),
-                            index=0,
-                            finish_reason=None,
-                        )
+                openai.types.chat.ChatCompletionChunk(
+                    object="chat.completion.chunk",
+                    choices=[],
+                    id="",
+                    created=0,
+                    model="",
+                    prompt_filter_results=[
+                        {
+                            "prompt_index": 0,
+                            "content_filter_results": {
+                                "hate": {"filtered": False, "severity": "safe"},
+                                "self_harm": {"filtered": False, "severity": "safe"},
+                                "sexual": {"filtered": False, "severity": "safe"},
+                                "violence": {"filtered": False, "severity": "safe"},
+                            },
+                        }
                     ],
-                ),
+                )
             ]
             answer_deltas = answer.split(" ")
             for answer_index, answer_delta in enumerate(answer_deltas):
-                # Completion chunks include whitespace, so we need to add it back in
-                if answer_index > 0:
+                # Text completion chunks include whitespace, so we need to add it back in
+                if answer_index > 0 and answer_delta != "</think>":
                     answer_delta = " " + answer_delta
                 self.chunks.append(
-                    azure.ai.inference.models.StreamingChatCompletionsUpdate(
+                    openai.types.chat.ChatCompletionChunk(
                         id="test-123",
-                        created=1703462735,
-                        model="DeepSeek-R1",
+                        object="chat.completion.chunk",
                         choices=[
-                            azure.ai.inference.models.StreamingChatChoiceUpdate(
-                                delta=azure.ai.inference.models.StreamingChatResponseMessageUpdate(
-                                    content=answer_delta, role=None
+                            openai.types.chat.chat_completion_chunk.Choice(
+                                delta=openai.types.chat.chat_completion_chunk.ChoiceDelta(
+                                    role=None, content=answer_delta
                                 ),
-                                index=0,
                                 finish_reason=None,
+                                index=0,
+                                logprobs=None,
+                                # Only Azure includes content_filter_results
+                                content_filter_results={
+                                    "hate": {"filtered": False, "severity": "safe"},
+                                    "self_harm": {"filtered": False, "severity": "safe"},
+                                    "sexual": {"filtered": False, "severity": "safe"},
+                                    "violence": {"filtered": False, "severity": "safe"},
+                                },
                             )
                         ],
+                        created=1703462735,
+                        model="DeepSeek-R1",
                     )
                 )
             self.chunks.append(
-                azure.ai.inference.models.StreamingChatCompletionsUpdate(
+                openai.types.chat.ChatCompletionChunk(
                     id="test-123",
-                    created=1703462735,
-                    model="DeepSeek-R1",
+                    object="chat.completion.chunk",
                     choices=[
-                        azure.ai.inference.models.StreamingChatChoiceUpdate(
-                            delta=azure.ai.inference.models.StreamingChatResponseMessageUpdate(content=None, role=None),
+                        openai.types.chat.chat_completion_chunk.Choice(
+                            delta=openai.types.chat.chat_completion_chunk.ChoiceDelta(content=None, role=None),
                             index=0,
                             finish_reason="stop",
+                            # Only Azure includes content_filter_results
+                            content_filter_results={},
                         )
                     ],
+                    created=1703462735,
+                    model="DeepSeek-R1",
                 )
             )
 
@@ -75,28 +91,29 @@ async def __anext__(self):
             else:
                 raise StopAsyncIteration
 
-    async def mock_complete(*args, **kwargs):
+    async def mock_acreate(*args, **kwargs):
         # Only mock a stream=True completion
         last_message = kwargs.get("messages")[-1]["content"]
         if last_message == "What is the capital of France?":
-            return AsyncChatCompletionIterator("The capital of France is Paris.")
+            return AsyncChatCompletionIterator("<think> hmm </think> The capital of France is Paris.")
         elif last_message == "What is the capital of Germany?":
-            return AsyncChatCompletionIterator("The capital of Germany is Berlin.")
+            return AsyncChatCompletionIterator("<think> hmm </think> The capital of Germany is Berlin.")
         else:
             raise ValueError(f"Unexpected message: {last_message}")
 
-    monkeypatch.setattr("azure.ai.inference.aio.ChatCompletionsClient.complete", mock_complete)
+    monkeypatch.setattr("openai.resources.chat.AsyncCompletions.create", mock_acreate)
 
 
 @pytest.fixture
 def mock_defaultazurecredential(monkeypatch):
-    monkeypatch.setattr("azure.identity.aio.DefaultAzureCredential", mock_cred.MockAzureCredential)
+    monkeypatch.setattr("azure.identity.aio.AzureDeveloperCliCredential", mock_cred.MockAzureCredential)
     monkeypatch.setattr("azure.identity.aio.ManagedIdentityCredential", mock_cred.MockAzureCredential)
 
 
 @pytest_asyncio.fixture
 async def client(monkeypatch, mock_openai_chatcompletion, mock_defaultazurecredential):
     monkeypatch.setenv("AZURE_INFERENCE_ENDPOINT", "test-deepseek-service.ai.azure.com")
+    monkeypatch.setenv("AZURE_TENANT_ID", "test-tenant-id")
 
     quart_app = quartapp.create_app(testing=True)
 
diff --git a/tests/mock_cred.py b/tests/mock_cred.py
index d8ea4a3..53a0e58 100644
--- a/tests/mock_cred.py
+++ b/tests/mock_cred.py
@@ -1,5 +1,10 @@
+import azure.core.credentials
 import azure.core.credentials_async
 
 
 class MockAzureCredential(azure.core.credentials_async.AsyncTokenCredential):
-    pass
+    async def get_token(self, *scopes, **kwargs):
+        return azure.core.credentials.AccessToken(
+            token="mock_token",
+            expires_on=1703462735,
+        )
diff --git a/tests/snapshots/test_app/test_chat_stream_text/result.jsonlines b/tests/snapshots/test_app/test_chat_stream_text/result.jsonlines
index b4f3f44..50730aa 100644
--- a/tests/snapshots/test_app/test_chat_stream_text/result.jsonlines
+++ b/tests/snapshots/test_app/test_chat_stream_text/result.jsonlines
@@ -1,4 +1,5 @@
-{"delta": {"content": "The", "reasoning_content": null, "role": "assistant"}}
+{"delta": {"content": null, "reasoning_content": " hmm", "role": "assistant"}}
+{"delta": {"content": " The", "reasoning_content": null, "role": "assistant"}}
 {"delta": {"content": " capital", "reasoning_content": null, "role": "assistant"}}
 {"delta": {"content": " of", "reasoning_content": null, "role": "assistant"}}
 {"delta": {"content": " France", "reasoning_content": null, "role": "assistant"}}
diff --git a/tests/snapshots/test_app/test_chat_stream_text_history/result.jsonlines b/tests/snapshots/test_app/test_chat_stream_text_history/result.jsonlines
index ba8dd58..42d9a6c 100644
--- a/tests/snapshots/test_app/test_chat_stream_text_history/result.jsonlines
+++ b/tests/snapshots/test_app/test_chat_stream_text_history/result.jsonlines
@@ -1,4 +1,5 @@
-{"delta": {"content": "The", "reasoning_content": null, "role": "assistant"}}
+{"delta": {"content": null, "reasoning_content": " hmm", "role": "assistant"}}
+{"delta": {"content": " The", "reasoning_content": null, "role": "assistant"}}
 {"delta": {"content": " capital", "reasoning_content": null, "role": "assistant"}}
 {"delta": {"content": " of", "reasoning_content": null, "role": "assistant"}}
 {"delta": {"content": " Germany", "reasoning_content": null, "role": "assistant"}}
diff --git a/tests/test_app.py b/tests/test_app.py
index a0e7259..abe6070 100644
--- a/tests/test_app.py
+++ b/tests/test_app.py
@@ -49,11 +49,12 @@ async def test_chat_stream_text_history(client, snapshot):
 async def test_openai_managedidentity(monkeypatch):
     monkeypatch.setenv("AZURE_CLIENT_ID", "test-client-id")
     monkeypatch.setenv("AZURE_INFERENCE_ENDPOINT", "test-deepseek-service.ai.azure.com")
+    monkeypatch.setenv("RUNNING_IN_PRODUCTION", "true")
 
     monkeypatch.setattr("azure.identity.aio.ManagedIdentityCredential", mock_cred.MockAzureCredential)
 
     quart_app = quartapp.create_app(testing=True)
 
     async with quart_app.test_app():
-        assert not isinstance(quart_app.blueprints["chat"].ai_client._config.credential, AzureKeyCredential)
-        assert isinstance(quart_app.blueprints["chat"].ai_client._config.credential, AsyncTokenCredential)
+        assert not isinstance(quart_app.blueprints["chat"].azure_credential, AzureKeyCredential)
+        assert isinstance(quart_app.blueprints["chat"].azure_credential, AsyncTokenCredential)