diff --git a/algoliasearch/http/api_response.py b/algoliasearch/http/api_response.py
index 8c5e0748e..aa7c7de7b 100644
--- a/algoliasearch/http/api_response.py
+++ b/algoliasearch/http/api_response.py
@@ -21,7 +21,7 @@ class ApiResponse(Generic[T]):
     def __init__(
         self,
         verb: Verb,
-        data: T = None,
+        data: Optional[T] = None,
         error_message: str = "",
         headers: Optional[Dict[str, str]] = None,
         host: str = "",
@@ -94,6 +94,6 @@ def deserialize(klass: Any = None, data: Any = None) -> Any:
             return data
 
         if isinstance(data, str):
-            return klass.from_json(data)
+            return klass.from_json(data)  # pyright: ignore
 
-        return klass.from_dict(data)
+        return klass.from_dict(data)  # pyright: ignore
diff --git a/algoliasearch/http/base_config.py b/algoliasearch/http/base_config.py
index 572bb27c2..4191a0bd5 100644
--- a/algoliasearch/http/base_config.py
+++ b/algoliasearch/http/base_config.py
@@ -5,20 +5,6 @@
 
 
 class BaseConfig:
-    app_id: Optional[str]
-    api_key: Optional[str]
-
-    read_timeout: int
-    write_timeout: int
-    connect_timeout: int
-
-    wait_task_time_before_retry: Optional[int]
-
-    headers: Dict[str, str]
-    proxies: Dict[str, str]
-
-    hosts: HostsCollection
-
     def __init__(self, app_id: Optional[str] = None, api_key: Optional[str] = None):
         app_id = environ.get("ALGOLIA_APP_ID") if app_id is None else app_id
 
@@ -36,12 +22,14 @@ def __init__(self, app_id: Optional[str] = None, api_key: Optional[str] = None):
         self.write_timeout = 30000
         self.connect_timeout = 2000
 
-        self.wait_task_time_before_retry = None
-        self.headers = None
-        self.proxies = None
-        self.hosts = None
+        self.wait_task_time_before_retry: Optional[int] = None
+        self.headers: Optional[Dict[str, str]] = None
+        self.proxies: Optional[Dict[str, str]] = None
+        self.hosts: Optional[HostsCollection] = None
 
     def set_client_api_key(self, api_key: str) -> None:
         """Sets a new API key to authenticate requests."""
         self.api_key = api_key
+        if self.headers is None:
+            self.headers = {}
         self.headers["x-algolia-api-key"] = api_key
diff --git a/algoliasearch/http/base_transporter.py b/algoliasearch/http/base_transporter.py
index 047663cca..b9404b1d6 100644
--- a/algoliasearch/http/base_transporter.py
+++ b/algoliasearch/http/base_transporter.py
@@ -7,14 +7,15 @@
 
 
 class BaseTransporter:
-    _config: BaseConfig
-    _retry_strategy: RetryStrategy
-    _hosts: List[Host]
-
     def __init__(self, config: BaseConfig) -> None:
         self._config = config
         self._retry_strategy = RetryStrategy()
-        self._hosts = []
+        self._hosts: List[Host] = []
+        self._timeout = 5000
+
+    @property
+    def config(self) -> BaseConfig:
+        return self._config
 
     def prepare(
         self,
@@ -25,13 +26,18 @@ def prepare(
 
         if use_read_transporter:
             self._timeout = request_options.timeouts["read"]
-            self._hosts = self._config.hosts.read()
+            self._hosts = (
+                self._config.hosts.read() if self._config.hosts is not None else []
+            )
             if isinstance(request_options.data, dict):
                 query_parameters.update(request_options.data)
-            return query_parameters
+        else:
+            self._timeout = request_options.timeouts["write"]
+            self._hosts = (
+                self._config.hosts.write() if self._config.hosts is not None else []
+            )
 
-        self._timeout = request_options.timeouts["write"]
-        self._hosts = self._config.hosts.write()
+        return query_parameters
 
     def build_path(self, path, query_parameters):
         if query_parameters is not None and len(query_parameters) > 0:
@@ -54,9 +60,21 @@ def build_url(self, host, path):
         )
 
     def get_proxy(self, url):
+        if self._config.proxies is None:
+            return None
+
         if url.startswith("https"):
             return self._config.proxies.get("https")
         elif url.startswith("http"):
             return self._config.proxies.get("http")
         else:
             return None
+
+    def get_proxies(self, url):
+        if self._config.proxies is None:
+            return None
+
+        if url.startswith("http"):
+            return self._config.proxies
+        else:
+            return None
diff --git a/algoliasearch/http/exceptions.py b/algoliasearch/http/exceptions.py
index 2e7e51406..0fa29f5a3 100644
--- a/algoliasearch/http/exceptions.py
+++ b/algoliasearch/http/exceptions.py
@@ -127,7 +127,12 @@ def __init__(self, msg, path_to_item=None) -> None:
 
 
 class ApiException(AlgoliaException):
-    def __init__(self, status_code=None, error_message=None, raw_data=None) -> None:
+    def __init__(
+        self,
+        status_code: int = -1,
+        error_message: str = "Unknown error",
+        raw_data: bytes = b"",
+    ) -> None:
         self.status_code = status_code
         self.error_message = error_message
         self.body = raw_data.decode("utf-8")
diff --git a/algoliasearch/http/helpers.py b/algoliasearch/http/helpers.py
index 196694d1c..a56994203 100644
--- a/algoliasearch/http/helpers.py
+++ b/algoliasearch/http/helpers.py
@@ -23,8 +23,8 @@ def __call__(self, retry_count: int = 0) -> int:
 async def create_iterable(
     func: Callable[[Optional[T]], Awaitable[T]],
     validate: Callable[[T], bool],
-    aggregator: Callable[[T], None],
-    timeout: Timeout = Timeout(),
+    aggregator: Optional[Callable[[T], None]],
+    timeout: Callable[[], int] = Timeout(),
     error_validate: Optional[Callable[[T], bool]] = None,
     error_message: Optional[Callable[[T], str]] = None,
 ) -> T:
@@ -55,8 +55,8 @@ async def retry(prev: Optional[T] = None) -> T:
 def create_iterable_sync(
     func: Callable[[Optional[T]], T],
     validate: Callable[[T], bool],
-    aggregator: Callable[[T], None],
-    timeout: Timeout = Timeout(),
+    aggregator: Optional[Callable[[T], None]],
+    timeout: Callable[[], int] = Timeout(),
     error_validate: Optional[Callable[[T], bool]] = None,
     error_message: Optional[Callable[[T], str]] = None,
 ) -> T:
diff --git a/algoliasearch/http/hosts.py b/algoliasearch/http/hosts.py
index 83544b4cc..c94351f11 100644
--- a/algoliasearch/http/hosts.py
+++ b/algoliasearch/http/hosts.py
@@ -18,8 +18,9 @@ def __init__(
         self.port = port
         self.priority = cast(int, priority)
         self.accept = (CallType.WRITE | CallType.READ) if accept is None else accept
-
-        self.reset()
+        self.last_use = 0.0
+        self.retry_count = 0
+        self.up = True
 
     def reset(self) -> None:
         self.last_use = 0.0
diff --git a/algoliasearch/http/request_options.py b/algoliasearch/http/request_options.py
index 41104a092..e22083162 100644
--- a/algoliasearch/http/request_options.py
+++ b/algoliasearch/http/request_options.py
@@ -1,6 +1,6 @@
 from copy import deepcopy
 from sys import version_info
-from typing import Any, Dict, List, Optional, Tuple, Union
+from typing import Any, Dict, Optional, Union
 from urllib.parse import quote
 
 from algoliasearch.http.base_config import BaseConfig
@@ -13,20 +13,20 @@
 
 
 class RequestOptions:
-    _config: BaseConfig
-    headers: Dict[str, str]
-    query_parameters: Dict[str, Any]
-    timeouts: Dict[str, int]
-    data: Dict[str, Any]
-
     def __init__(
         self,
         config: BaseConfig,
-        headers: Dict[str, str] = {},
-        query_parameters: Dict[str, Any] = {},
-        timeouts: Dict[str, int] = {},
-        data: Dict[str, Any] = {},
+        headers: Optional[Dict[str, str]] = None,
+        query_parameters: Optional[Dict[str, Any]] = None,
+        timeouts: Optional[Dict[str, int]] = None,
+        data: Optional[Dict[str, Any]] = None,
     ) -> None:
+        if headers is None:
+            headers = {}
+        if query_parameters is None:
+            query_parameters = {}
+        if timeouts is None:
+            timeouts = {}
         self._config = config
         self.headers = headers
         self.query_parameters = {
@@ -51,13 +51,12 @@ def from_dict(self, data: Dict[str, Dict[str, Any]]) -> Self:
             query_parameters=data.get("query_parameters", {}),
             timeouts=data.get("timeouts", {}),
             data=data.get("data", {}),
-        )
+        )  # pyright: ignore
 
     def merge(
         self,
-        query_parameters: List[Tuple[str, str]] = [],
-        headers: Dict[str, Optional[str]] = {},
-        _: Dict[str, int] = {},
+        query_parameters: Optional[Dict[str, Any]] = None,
+        headers: Optional[Dict[str, str]] = None,
         data: Optional[str] = None,
         user_request_options: Optional[Union[Self, Dict[str, Any]]] = None,
     ) -> Self:
@@ -65,11 +64,15 @@ def merge(
         Merges the default config values with the user given request options if it exists.
         """
 
-        headers.update(self._config.headers)
+        if query_parameters is None:
+            query_parameters = {}
+        if headers is None:
+            headers = {}
+        headers.update(self._config.headers or {})
 
         request_options = {
             "headers": headers,
-            "query_parameters": {k: v for k, v in query_parameters},
+            "query_parameters": query_parameters,
             "timeouts": {
                 "read": self._config.read_timeout,
                 "write": self._config.write_timeout,
diff --git a/algoliasearch/http/retry.py b/algoliasearch/http/retry.py
index e42670de6..8a5a48b34 100644
--- a/algoliasearch/http/retry.py
+++ b/algoliasearch/http/retry.py
@@ -14,7 +14,7 @@ class RetryOutcome:
 class RetryStrategy:
     def valid_hosts(self, hosts: List[Host]) -> List[Host]:
         for host in hosts:
-            if not host.up and self._now() - host.last_use > Host.TTL:
+            if not host.up and time.time() - host.last_use > Host.TTL:
                 host.up = True
 
         return [host for host in hosts if host.up]
diff --git a/algoliasearch/http/serializer.py b/algoliasearch/http/serializer.py
index 52bba424c..3a71105cf 100644
--- a/algoliasearch/http/serializer.py
+++ b/algoliasearch/http/serializer.py
@@ -10,7 +10,16 @@ class QueryParametersSerializer:
     Parses the given 'query_parameters' values of each keys into their string value.
     """
 
-    query_parameters: Dict[str, Any] = {}
+    def __init__(self, query_parameters: Optional[Dict[str, Any]]) -> None:
+        self.query_parameters: Dict[str, Any] = {}
+        if query_parameters is None:
+            return
+        for key, value in query_parameters.items():
+            if isinstance(value, dict):
+                for dkey, dvalue in value.items():
+                    self.query_parameters[dkey] = self.parse(dvalue)
+            else:
+                self.query_parameters[key] = self.parse(value)
 
     def parse(self, value) -> Any:
         if isinstance(value, list):
@@ -27,19 +36,8 @@ def encoded(self) -> str:
             dict(sorted(self.query_parameters.items(), key=lambda val: val[0]))
         ).replace("+", "%20")
 
-    def __init__(self, query_parameters: Optional[Dict[str, Any]]) -> None:
-        self.query_parameters = {}
-        if query_parameters is None:
-            return
-        for key, value in query_parameters.items():
-            if isinstance(value, dict):
-                for dkey, dvalue in value.items():
-                    self.query_parameters[dkey] = self.parse(dvalue)
-            else:
-                self.query_parameters[key] = self.parse(value)
-
 
-def bodySerializer(obj: Any) -> Any:
+def body_serializer(obj: Any) -> Any:
     """Builds a JSON POST object.
 
     If obj is None, return None.
@@ -57,9 +55,9 @@ def bodySerializer(obj: Any) -> Any:
     elif isinstance(obj, PRIMITIVE_TYPES):
         return obj
     elif isinstance(obj, list):
-        return [bodySerializer(sub_obj) for sub_obj in obj]
+        return [body_serializer(sub_obj) for sub_obj in obj]
     elif isinstance(obj, tuple):
-        return tuple(bodySerializer(sub_obj) for sub_obj in obj)
+        return tuple(body_serializer(sub_obj) for sub_obj in obj)
     elif isinstance(obj, dict):
         obj_dict = obj
     else:
@@ -67,4 +65,4 @@ def bodySerializer(obj: Any) -> Any:
         if obj_dict is None:
             return None
 
-    return {key: bodySerializer(val) for key, val in obj_dict.items()}
+    return {key: body_serializer(val) for key, val in obj_dict.items()}
diff --git a/algoliasearch/http/transporter.py b/algoliasearch/http/transporter.py
index a52e31276..b82d7aac5 100644
--- a/algoliasearch/http/transporter.py
+++ b/algoliasearch/http/transporter.py
@@ -1,5 +1,6 @@
 from asyncio import TimeoutError
 from json import loads
+from typing import List, Optional
 
 from aiohttp import ClientSession, TCPConnector
 from async_timeout import timeout
@@ -11,19 +12,19 @@
     AlgoliaUnreachableHostException,
     RequestException,
 )
+from algoliasearch.http.hosts import Host
 from algoliasearch.http.request_options import RequestOptions
 from algoliasearch.http.retry import RetryOutcome, RetryStrategy
 from algoliasearch.http.verb import Verb
 
 
 class Transporter(BaseTransporter):
-    _session: ClientSession
-
     def __init__(self, config: BaseConfig) -> None:
-        self._session = None
+        super().__init__(config)
+        self._session: Optional[ClientSession] = None
         self._config = config
         self._retry_strategy = RetryStrategy()
-        self._hosts = []
+        self._hosts: List[Host] = []
 
     async def close(self) -> None:
         if self._session is not None:
@@ -71,7 +72,7 @@ async def request(
                         url=url,
                         host=host.url,
                         status_code=resp.status,
-                        headers=resp.headers,
+                        headers=resp.headers,  # pyright: ignore # insensitive dict is still a dict
                         data=_raw_data,
                         raw_data=_raw_data,
                         error_message=str(resp.reason),
@@ -103,6 +104,7 @@ async def request(
 
 class EchoTransporter(Transporter):
     def __init__(self, config: BaseConfig) -> None:
+        super().__init__(config)
         self._config = config
         self._retry_strategy = RetryStrategy()
 
diff --git a/algoliasearch/http/transporter_sync.py b/algoliasearch/http/transporter_sync.py
index cba92ba1a..4d11a55e4 100644
--- a/algoliasearch/http/transporter_sync.py
+++ b/algoliasearch/http/transporter_sync.py
@@ -4,9 +4,9 @@
 from requests import Request, Session, Timeout
 
 if version_info >= (3, 11):
-    from typing import Self
+    from typing import List, Optional, Self
 else:
-    from typing_extensions import Self
+    from typing_extensions import List, Self
 
 from requests.adapters import HTTPAdapter
 from urllib3.util import Retry
@@ -18,19 +18,19 @@
     AlgoliaUnreachableHostException,
     RequestException,
 )
+from algoliasearch.http.hosts import Host
 from algoliasearch.http.request_options import RequestOptions
 from algoliasearch.http.retry import RetryOutcome, RetryStrategy
 from algoliasearch.http.verb import Verb
 
 
 class TransporterSync(BaseTransporter):
-    _session: Session
-
     def __init__(self, config: BaseConfig) -> None:
-        self._session = None
+        super().__init__(config)
+        self._session: Optional[Session] = None
         self._config = config
         self._retry_strategy = RetryStrategy()
-        self._hosts = []
+        self._hosts: List[Host] = []
 
     def __enter__(self) -> Self:
         return self
@@ -64,7 +64,7 @@ def request(
 
         for host in self._retry_strategy.valid_hosts(self._hosts):
             url = self.build_url(host, path)
-            proxy = self.get_proxy(url)
+            proxies = self.get_proxies(url)
 
             req = Request(
                 method=verb,
@@ -77,7 +77,7 @@ def request(
                 resp = self._session.send(
                     req,
                     timeout=self._timeout / 1000,
-                    proxies=proxy,
+                    proxies=proxies,
                 )
 
                 response = ApiResponse(
@@ -86,7 +86,7 @@ def request(
                     url=url,
                     host=host.url,
                     status_code=resp.status_code,
-                    headers=resp.headers,  # type: ignore -- insensitive dict is still a dict
+                    headers=resp.headers,  # type: ignore # insensitive dict is still a dict
                     data=resp.text,
                     raw_data=resp.text,
                     error_message=str(resp.reason),
@@ -117,6 +117,7 @@ def request(
 
 class EchoTransporterSync(TransporterSync):
     def __init__(self, config: BaseConfig) -> None:
+        super().__init__(config)
         self._config = config
         self._retry_strategy = RetryStrategy()
 
diff --git a/algoliasearch/http/user_agent.py b/algoliasearch/http/user_agent.py
index 63545e0e0..edaf03f03 100644
--- a/algoliasearch/http/user_agent.py
+++ b/algoliasearch/http/user_agent.py
@@ -11,14 +11,14 @@
 
 
 class UserAgent:
+    def __init__(self) -> None:
+        self.value = "Algolia for Python ({}); Python ({})".format(
+            __version__, str(python_version())
+        )
+
     def get(self) -> str:
         return self.value
 
     def add(self, segment: str, version: Optional[str] = __version__) -> Self:
         self.value += "; {} ({})".format(segment, version)
         return self
-
-    def __init__(self) -> None:
-        self.value = "Algolia for Python ({}); Python ({})".format(
-            __version__, str(python_version())
-        )
diff --git a/algoliasearch/http/verb.py b/algoliasearch/http/verb.py
index ebd7e5b94..3e8af8129 100644
--- a/algoliasearch/http/verb.py
+++ b/algoliasearch/http/verb.py
@@ -1,4 +1,7 @@
-class Verb:
+from enum import Enum
+
+
+class Verb(str, Enum):
     GET = "GET"
     POST = "POST"
     PUT = "PUT"