apify · vdusek · Jun 8, 2026 · Jun 8, 2026
diff --git a/src/crawlee/_request.py b/src/crawlee/_request.py
@@ -6,6 +6,7 @@
 from typing import TYPE_CHECKING, Annotated, Any, TypedDict, cast
 
 from pydantic import BaseModel, BeforeValidator, ConfigDict, Field, PlainSerializer, PlainValidator, TypeAdapter
+from pydantic.alias_generators import to_camel
 from yarl import URL
 
 from crawlee._types import EnqueueStrategy, HttpHeaders, HttpMethod, HttpPayload, JsonSerializable
@@ -34,31 +35,33 @@ class RequestState(IntEnum):
 class CrawleeRequestData(BaseModel):
     """Crawlee-specific configuration stored in the `user_data`."""
 
-    max_retries: Annotated[int | None, Field(alias='maxRetries', frozen=True)] = None
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
+
+    max_retries: Annotated[int | None, Field(frozen=True)] = None
     """Maximum number of retries for this request. Allows to override the global `max_request_retries` option of
     `BasicCrawler`."""
 
-    enqueue_strategy: Annotated[EnqueueStrategy | None, Field(alias='enqueueStrategy')] = None
+    enqueue_strategy: EnqueueStrategy | None = None
     """The strategy that was used for enqueuing the request."""
 
     state: RequestState = RequestState.UNPROCESSED
     """Describes the request's current lifecycle state."""
 
-    session_rotation_count: Annotated[int | None, Field(alias='sessionRotationCount')] = None
+    session_rotation_count: int | None = None
     """The number of finished session rotations for this request."""
 
-    skip_navigation: Annotated[bool, Field(alias='skipNavigation')] = False
+    skip_navigation: bool = False
 
-    last_proxy_tier: Annotated[int | None, Field(alias='lastProxyTier')] = None
+    last_proxy_tier: int | None = None
     """The last proxy tier used to process the request."""
 
-    forefront: Annotated[bool, Field()] = False
+    forefront: bool = False
     """Indicate whether the request should be enqueued at the front of the queue."""
 
-    crawl_depth: Annotated[int, Field(alias='crawlDepth')] = 0
+    crawl_depth: int = 0
     """The depth of the request in the crawl tree."""
 
-    session_id: Annotated[str | None, Field()] = None
+    session_id: str | None = None
     """ID of a session to which the request is bound."""
 
 
@@ -166,9 +169,9 @@ class Request(BaseModel):
     ```
     """
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
-    unique_key: Annotated[str, Field(alias='uniqueKey', frozen=True)]
+    unique_key: Annotated[str, Field(frozen=True)]
     """A unique key identifying the request. Two requests with the same `unique_key` are considered as pointing
     to the same URL.
 
@@ -212,7 +215,7 @@ class Request(BaseModel):
         # Internally, the model contains `UserData`, this is just for convenience
         user_data: Annotated[
             MutableMapping[str, JsonSerializable],
-            Field(alias='userData', default_factory=UserData),
+            Field(default_factory=UserData),
             PlainValidator(user_data_adapter.validate_python),
             PlainSerializer(
                 lambda instance: user_data_adapter.dump_python(
@@ -228,16 +231,16 @@ class Request(BaseModel):
         request's scope, keeping them accessible on retries, failures etc.
         """
 
-    retry_count: Annotated[int, Field(alias='retryCount')] = 0
+    retry_count: int = 0
     """Number of times the request has been retried."""
 
-    no_retry: Annotated[bool, Field(alias='noRetry')] = False
+    no_retry: bool = False
     """If set to `True`, the request will not be retried in case of failure."""
 
-    loaded_url: Annotated[str | None, BeforeValidator(validate_http_url), Field(alias='loadedUrl')] = None
+    loaded_url: Annotated[str | None, BeforeValidator(validate_http_url)] = None
     """URL of the web page that was loaded. This can differ from the original URL in case of redirects."""
 
-    handled_at: Annotated[datetime | None, Field(alias='handledAt')] = None
+    handled_at: datetime | None = None
     """Timestamp when the request was handled."""
 
     @classmethod
@@ -434,5 +437,5 @@ def was_already_handled(self) -> bool:
 class RequestWithLock(Request):
     """A crawling request with information about locks."""
 
-    lock_expires_at: Annotated[datetime, Field(alias='lockExpiresAt')]
+    lock_expires_at: datetime
     """The timestamp when the lock expires."""
diff --git a/src/crawlee/_utils/system.py b/src/crawlee/_utils/system.py
@@ -9,6 +9,7 @@
 
 import psutil
 from pydantic import BaseModel, ConfigDict, Field, PlainSerializer, PlainValidator
+from pydantic.alias_generators import to_camel
 
 from crawlee._utils.byte_size import ByteSize
 
@@ -36,36 +37,29 @@ def _get_used_memory(process: psutil.Process) -> int:
 class CpuInfo(BaseModel):
     """Information about the CPU usage."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
-    used_ratio: Annotated[float, Field(alias='usedRatio')]
+    used_ratio: float
     """The ratio of CPU currently in use, represented as a float between 0 and 1."""
 
     # Workaround for Pydantic and type checkers when using Annotated with default_factory
     if TYPE_CHECKING:
         created_at: datetime = datetime.now(timezone.utc)
         """The time at which the measurement was taken."""
     else:
-        created_at: Annotated[
-            datetime,
-            Field(
-                alias='createdAt',
-                default_factory=lambda: datetime.now(timezone.utc),
-            ),
-        ]
+        created_at: Annotated[datetime, Field(default_factory=lambda: datetime.now(timezone.utc))]
         """The time at which the measurement was taken."""
 
 
 class MemoryUsageInfo(BaseModel):
     """Information about the memory usage."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
     current_size: Annotated[
         ByteSize,
         PlainValidator(ByteSize.validate),
         PlainSerializer(lambda size: size.bytes),
-        Field(alias='currentSize'),
     ]
     """Memory usage of the current Python process and its children."""
 
@@ -74,31 +68,22 @@ class MemoryUsageInfo(BaseModel):
         created_at: datetime = datetime.now(timezone.utc)
         """The time at which the measurement was taken."""
     else:
-        created_at: Annotated[
-            datetime,
-            Field(
-                alias='createdAt',
-                default_factory=lambda: datetime.now(timezone.utc),
-            ),
-        ]
+        created_at: Annotated[datetime, Field(default_factory=lambda: datetime.now(timezone.utc))]
         """The time at which the measurement was taken."""
 
 
 class MemoryInfo(MemoryUsageInfo):
     """Information about system memory."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
-    total_size: Annotated[
-        ByteSize, PlainValidator(ByteSize.validate), PlainSerializer(lambda size: size.bytes), Field(alias='totalSize')
-    ]
+    total_size: Annotated[ByteSize, PlainValidator(ByteSize.validate), PlainSerializer(lambda size: size.bytes)]
     """Total memory available in the system."""
 
     system_wide_used_size: Annotated[
         ByteSize,
         PlainValidator(ByteSize.validate),
         PlainSerializer(lambda size: size.bytes),
-        Field(alias='systemWideUsedSize'),
     ]
     """Total memory used by all processes system-wide (including non-crawlee processes)."""
 

diff --git a/src/crawlee/crawlers/_adaptive_playwright/_adaptive_playwright_crawler_statistics.py b/src/crawlee/crawlers/_adaptive_playwright/_adaptive_playwright_crawler_statistics.py
@@ -1,8 +1,7 @@
 from __future__ import annotations
 
-from typing import Annotated
-
-from pydantic import ConfigDict, Field
+from pydantic import ConfigDict
+from pydantic.alias_generators import to_camel
 
 from crawlee._utils.docs import docs_group
 from crawlee.statistics import StatisticsState
@@ -12,13 +11,15 @@
 class AdaptivePlaywrightCrawlerStatisticState(StatisticsState):
     """Statistic data about a crawler run with additional information related to adaptive crawling."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, ser_json_inf_nan='constants')
+    model_config = ConfigDict(
+        validate_by_name=True, validate_by_alias=True, alias_generator=to_camel, ser_json_inf_nan='constants'
+    )
 
-    http_only_request_handler_runs: Annotated[int, Field(alias='http_only_request_handler_runs')] = 0
+    http_only_request_handler_runs: int = 0
     """Number representing how many times static http based crawling was used."""
 
-    browser_request_handler_runs: Annotated[int, Field(alias='browser_request_handler_runs')] = 0
+    browser_request_handler_runs: int = 0
     """Number representing how many times browser based crawling was used."""
 
-    rendering_type_mispredictions: Annotated[int, Field(alias='rendering_type_mispredictions')] = 0
+    rendering_type_mispredictions: int = 0
     """Number representing how many times the predictor gave incorrect prediction."""
diff --git a/src/crawlee/crawlers/_adaptive_playwright/_rendering_type_predictor.py b/src/crawlee/crawlers/_adaptive_playwright/_rendering_type_predictor.py
@@ -11,6 +11,7 @@
 
 from jaro import jaro_winkler_metric
 from pydantic import BaseModel, ConfigDict, Field, PlainSerializer, PlainValidator
+from pydantic.alias_generators import to_camel
 from sklearn.linear_model import LogisticRegression
 from typing_extensions import override
 
@@ -32,7 +33,7 @@
 
 
 class RenderingTypePredictorState(BaseModel):
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
     model: Annotated[
         LogisticRegression,
@@ -41,7 +42,7 @@ class RenderingTypePredictorState(BaseModel):
         PlainSerializer(sklearn_model_serializer),
     ]
 
-    labels_coefficients: Annotated[defaultdict[str, float], Field(alias='labelsCoefficients')]
+    labels_coefficients: defaultdict[str, float]
 
 
 @docs_group('Other')

diff --git a/src/crawlee/events/_types.py b/src/crawlee/events/_types.py
@@ -5,6 +5,7 @@
 from typing import Annotated, Any, TypeVar
 
 from pydantic import BaseModel, ConfigDict, Field
+from pydantic.alias_generators import to_camel
 
 from crawlee._utils.docs import docs_group
 from crawlee._utils.models import timedelta_secs
@@ -40,29 +41,26 @@ class Event(str, Enum):
 class EventPersistStateData(BaseModel):
     """Data for the persist state event."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
-    is_migrating: Annotated[bool, Field(alias='isMigrating')]
+    is_migrating: bool
 
 
 @docs_group('Event data')
 class EventSystemInfoData(BaseModel):
     """Data for the system info event."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
-    cpu_info: Annotated[CpuInfo, Field(alias='cpuInfo')]
-    memory_info: Annotated[
-        MemoryUsageInfo,
-        Field(alias='memoryInfo'),
-    ]
+    cpu_info: CpuInfo
+    memory_info: MemoryUsageInfo
 
 
 @docs_group('Event data')
 class EventMigratingData(BaseModel):
     """Data for the migrating event."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
     # The remaining time in seconds before the migration is forced and the process is killed
     # Optional because it's not present when the event handler is called manually
@@ -73,21 +71,21 @@ class EventMigratingData(BaseModel):
 class EventAbortingData(BaseModel):
     """Data for the aborting event."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
 
 @docs_group('Event data')
 class EventExitData(BaseModel):
     """Data for the exit event."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
 
 @docs_group('Event data')
 class EventCrawlerStatusData(BaseModel):
     """Data for the crawler status event."""
 
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
     message: str
     """A message describing the current status of the crawler."""

diff --git a/src/crawlee/fingerprint_suite/_types.py b/src/crawlee/fingerprint_suite/_types.py
@@ -1,8 +1,9 @@
 from __future__ import annotations
 
-from typing import Annotated, Literal
+from typing import Literal
 
-from pydantic import BaseModel, ConfigDict, Field
+from pydantic import BaseModel, ConfigDict
+from pydantic.alias_generators import to_camel
 
 SupportedOperatingSystems = Literal['windows', 'macos', 'linux', 'android', 'ios']
 SupportedDevices = Literal['desktop', 'mobile']
@@ -11,32 +12,32 @@
 
 
 class ScreenOptions(BaseModel):
-    model_config = ConfigDict(extra='forbid', validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(extra='forbid', validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
     """Defines the screen constrains for the fingerprint generator."""
 
-    min_width: Annotated[float | None, Field(alias='minWidth')] = None
+    min_width: float | None = None
     """Minimal screen width constraint for the fingerprint generator."""
 
-    max_width: Annotated[float | None, Field(alias='maxWidth')] = None
+    max_width: float | None = None
     """Maximal screen width constraint for the fingerprint generator."""
 
-    min_height: Annotated[float | None, Field(alias='minHeight')] = None
+    min_height: float | None = None
     """Minimal screen height constraint for the fingerprint generator."""
 
-    max_height: Annotated[float | None, Field(alias='maxHeight')] = None
+    max_height: float | None = None
     """Maximal screen height constraint for the fingerprint generator."""
 
 
 class HeaderGeneratorOptions(BaseModel):
     """Collection of header related attributes that can be used by the fingerprint generator."""
 
-    model_config = ConfigDict(extra='forbid', validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(extra='forbid', validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
     browsers: list[SupportedBrowserType] | None = None
     """List of BrowserSpecifications to generate the headers for."""
 
-    operating_systems: Annotated[list[SupportedOperatingSystems] | None, Field(alias='operatingSystems')] = None
+    operating_systems: list[SupportedOperatingSystems] | None = None
     """List of operating systems to generate the headers for."""
 
     devices: list[SupportedDevices] | None = None
@@ -47,7 +48,7 @@ class HeaderGeneratorOptions(BaseModel):
     (https://developer.mozilla.org/en-US/docs/Web/HTTP/Headers/Accept-Language) request header
     in the language format accepted by that header, for example `en`, `en-US` or `de`."""
 
-    http_version: Annotated[SupportedHttpVersion | None, Field(alias='httpVersion')] = None
+    http_version: SupportedHttpVersion | None = None
     """HTTP version to be used for header generation (the headers differ depending on the version)."""
 
     strict: bool | None = None

diff --git a/src/crawlee/request_loaders/_request_list.py b/src/crawlee/request_loaders/_request_list.py
@@ -7,6 +7,7 @@
 from typing import Annotated
 
 from pydantic import BaseModel, ConfigDict, Field, ValidationError
+from pydantic.alias_generators import to_camel
 from typing_extensions import override
 
 from crawlee._request import Request
@@ -17,11 +18,11 @@
 
 
 class RequestListState(BaseModel):
-    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True)
+    model_config = ConfigDict(validate_by_name=True, validate_by_alias=True, alias_generator=to_camel)
 
-    next_index: Annotated[int, Field(alias='nextIndex')] = 0
-    next_unique_key: Annotated[str | None, Field(alias='nextUniqueKey')] = None
-    in_progress: Annotated[set[str], Field(alias='inProgress')] = set()
+    next_index: int = 0
+    next_unique_key: str | None = None
+    in_progress: set[str] = set()
 
 
 class RequestListData(BaseModel):