diff --git a/tests/e2e/test_coord.py b/tests/e2e/test_coord.py
index fc510b4..86d05eb 100644
--- a/tests/e2e/test_coord.py
+++ b/tests/e2e/test_coord.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.coord import ecef_to_wgs84, euler_to_quaternion
 
 # --- ECEF → WGS84 ---
diff --git a/tests/e2e/test_dataset_base.py b/tests/e2e/test_dataset_base.py
index 4eb7132..784e191 100644
--- a/tests/e2e/test_dataset_base.py
+++ b/tests/e2e/test_dataset_base.py
@@ -2,6 +2,8 @@
 
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetAdapter,
     DatasetCapabilities,
diff --git a/tests/e2e/test_download.py b/tests/e2e/test_download.py
index 3c32d70..8445eb8 100644
--- a/tests/e2e/test_download.py
+++ b/tests/e2e/test_download.py
@@ -3,6 +3,10 @@
 import hashlib
 from pathlib import Path
 
+import pytest
+
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.download import (
     DATASET_REGISTRY,
     DatasetSpec,
diff --git a/tests/e2e/test_euroc.py b/tests/e2e/test_euroc.py
index 23f8b69..4d479e7 100644
--- a/tests/e2e/test_euroc.py
+++ b/tests/e2e/test_euroc.py
@@ -13,6 +13,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.euroc import EuRoCAdapter
 from gps_denied.testing.harness import E2EHarness
 from gps_denied.testing.metrics import absolute_trajectory_error
diff --git a/tests/e2e/test_euroc_adapter.py b/tests/e2e/test_euroc_adapter.py
index 55e3189..b4cc33b 100644
--- a/tests/e2e/test_euroc_adapter.py
+++ b/tests/e2e/test_euroc_adapter.py
@@ -4,6 +4,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetNotAvailableError,
     PlatformClass,
diff --git a/tests/e2e/test_euroc_mh_all.py b/tests/e2e/test_euroc_mh_all.py
index fa73822..3a095a8 100644
--- a/tests/e2e/test_euroc_mh_all.py
+++ b/tests/e2e/test_euroc_mh_all.py
@@ -17,6 +17,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.euroc import EuRoCAdapter
 from gps_denied.testing.harness import E2EHarness
 from gps_denied.testing.metrics import absolute_trajectory_error
diff --git a/tests/e2e/test_euroc_vo_only.py b/tests/e2e/test_euroc_vo_only.py
index 957fb33..480333c 100644
--- a/tests/e2e/test_euroc_vo_only.py
+++ b/tests/e2e/test_euroc_vo_only.py
@@ -20,6 +20,8 @@ import cv2
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.core.vo import ORBVisualOdometry
 from gps_denied.schemas import CameraParameters
 from gps_denied.testing.datasets.euroc import EuRoCAdapter
diff --git a/tests/e2e/test_harness_smoke.py b/tests/e2e/test_harness_smoke.py
index 1eb5396..3e5637b 100644
--- a/tests/e2e/test_harness_smoke.py
+++ b/tests/e2e/test_harness_smoke.py
@@ -7,6 +7,8 @@ Correctness of VO on synthetic is out of scope — that's unit-test territory.
 
 import pytest
 
+pytestmark = [pytest.mark.integration]
+
 from gps_denied.testing.datasets.synthetic import SyntheticAdapter
 from gps_denied.testing.harness import E2EHarness, HarnessResult
 
diff --git a/tests/e2e/test_mars_lvig.py b/tests/e2e/test_mars_lvig.py
index 0da90d2..a78ea98 100644
--- a/tests/e2e/test_mars_lvig.py
+++ b/tests/e2e/test_mars_lvig.py
@@ -4,6 +4,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.mars_lvig import MARSLVIGAdapter
 from gps_denied.testing.harness import E2EHarness
 
diff --git a/tests/e2e/test_mars_lvig_adapter.py b/tests/e2e/test_mars_lvig_adapter.py
index 040f248..706d718 100644
--- a/tests/e2e/test_mars_lvig_adapter.py
+++ b/tests/e2e/test_mars_lvig_adapter.py
@@ -4,6 +4,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetNotAvailableError,
     PlatformClass,
diff --git a/tests/e2e/test_metrics.py b/tests/e2e/test_metrics.py
index 3405c02..158cd74 100644
--- a/tests/e2e/test_metrics.py
+++ b/tests/e2e/test_metrics.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.metrics import (
     absolute_trajectory_error,
     relative_pose_error,
diff --git a/tests/e2e/test_synthetic_adapter.py b/tests/e2e/test_synthetic_adapter.py
index 1f65a5b..33feb33 100644
--- a/tests/e2e/test_synthetic_adapter.py
+++ b/tests/e2e/test_synthetic_adapter.py
@@ -1,8 +1,11 @@
 """SyntheticAdapter produces a deterministic straight-line trajectory."""
 
 import numpy as np
+import pytest
 
 from gps_denied.testing.datasets.base import PlatformClass
+
+pytestmark = [pytest.mark.unit]
 from gps_denied.testing.datasets.synthetic import SyntheticAdapter
 
 
diff --git a/tests/e2e/test_vpair.py b/tests/e2e/test_vpair.py
index 052b51a..7c74c43 100644
--- a/tests/e2e/test_vpair.py
+++ b/tests/e2e/test_vpair.py
@@ -8,6 +8,8 @@ from pathlib import Path
 
 import pytest
 
+pytestmark = [pytest.mark.e2e]
+
 from gps_denied.testing.datasets.vpair import VPAIRAdapter
 from gps_denied.testing.harness import E2EHarness
 from gps_denied.testing.metrics import absolute_trajectory_error
diff --git a/tests/e2e/test_vpair_adapter.py b/tests/e2e/test_vpair_adapter.py
index a8e2e93..8c59eea 100644
--- a/tests/e2e/test_vpair_adapter.py
+++ b/tests/e2e/test_vpair_adapter.py
@@ -10,6 +10,8 @@ from pathlib import Path
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.testing.datasets.base import (
     DatasetNotAvailableError,
     PlatformClass,
diff --git a/tests/test_acceptance.py b/tests/test_acceptance.py
index 1c72704..1a66404 100644
--- a/tests/test_acceptance.py
+++ b/tests/test_acceptance.py
@@ -13,6 +13,8 @@ from unittest.mock import AsyncMock, MagicMock
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.integration]
+
 from gps_denied.core.chunk_manager import RouteChunkManager
 from gps_denied.core.gpr import GlobalPlaceRecognition
 from gps_denied.core.graph import FactorGraphOptimizer
diff --git a/tests/test_accuracy.py b/tests/test_accuracy.py
index efe1055..4ca8d64 100644
--- a/tests/test_accuracy.py
+++ b/tests/test_accuracy.py
@@ -22,6 +22,8 @@ import time
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.integration]
+
 from gps_denied.core.benchmark import (
     AccuracyBenchmark,
     BenchmarkResult,
diff --git a/tests/test_api_flights.py b/tests/test_api_flights.py
index 8fd0c7f..1e4789f 100644
--- a/tests/test_api_flights.py
+++ b/tests/test_api_flights.py
@@ -3,6 +3,9 @@
 import json
 
 import pytest
+
+pytestmark = [pytest.mark.integration]
+
 from httpx import ASGITransport, AsyncClient
 from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
 
diff --git a/tests/test_chunk_manager.py b/tests/test_chunk_manager.py
index 6e0a1e4..12d19bb 100644
--- a/tests/test_chunk_manager.py
+++ b/tests/test_chunk_manager.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.chunk_manager import RouteChunkManager
 from gps_denied.core.graph import FactorGraphOptimizer
 from gps_denied.schemas.chunk import ChunkStatus
diff --git a/tests/test_coordinates.py b/tests/test_coordinates.py
index 3a4fe86..9a231b3 100644
--- a/tests/test_coordinates.py
+++ b/tests/test_coordinates.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.coordinates import (
     CoordinateTransformer,
     OriginNotSetError,
diff --git a/tests/test_database.py b/tests/test_database.py
index 2a8d38c..c9a173c 100644
--- a/tests/test_database.py
+++ b/tests/test_database.py
@@ -1,6 +1,9 @@
 """Tests for the database layer — CRUD, cascade, transactions."""
 
 import pytest
+
+pytestmark = [pytest.mark.integration]
+
 from sqlalchemy import event
 from sqlalchemy.ext.asyncio import AsyncSession, async_sessionmaker, create_async_engine
 
diff --git a/tests/test_eskf.py b/tests/test_eskf.py
index 626b6c4..4eb473f 100644
--- a/tests/test_eskf.py
+++ b/tests/test_eskf.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.coordinates import CoordinateTransformer
 from gps_denied.core.eskf import ESKF
 from gps_denied.schemas import GPSPoint
diff --git a/tests/test_gpr.py b/tests/test_gpr.py
index ba1e411..34ae31d 100644
--- a/tests/test_gpr.py
+++ b/tests/test_gpr.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.gpr import GlobalPlaceRecognition
 from gps_denied.core.models import ModelManager
 from gps_denied.schemas.gpr import TileCandidate
diff --git a/tests/test_gps_input_encoding.py b/tests/test_gps_input_encoding.py
index ac24d8b..8bd8d6b 100644
--- a/tests/test_gps_input_encoding.py
+++ b/tests/test_gps_input_encoding.py
@@ -17,6 +17,8 @@ import time
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.blackbox]
+
 from gps_denied.core.mavlink import _confidence_to_fix_type, _eskf_to_gps_input
 from gps_denied.schemas import GPSPoint
 from gps_denied.schemas.eskf import ConfidenceTier, ESKFState
diff --git a/tests/test_graph.py b/tests/test_graph.py
index 6d3fccd..43f112f 100644
--- a/tests/test_graph.py
+++ b/tests/test_graph.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.graph import FactorGraphOptimizer
 from gps_denied.schemas import GPSPoint
 from gps_denied.schemas.graph import FactorGraphConfig
diff --git a/tests/test_health.py b/tests/test_health.py
index 61524bf..d696082 100644
--- a/tests/test_health.py
+++ b/tests/test_health.py
@@ -1,6 +1,9 @@
 """Tests for the health endpoint."""
 
 import pytest
+
+pytestmark = [pytest.mark.integration]
+
 from httpx import ASGITransport, AsyncClient
 
 from gps_denied.app import app
diff --git a/tests/test_mavlink.py b/tests/test_mavlink.py
index 3bbd21d..8d0d5a6 100644
--- a/tests/test_mavlink.py
+++ b/tests/test_mavlink.py
@@ -14,6 +14,8 @@ import time
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.mavlink import (
     MAVLinkBridge,
     MockMAVConnection,
diff --git a/tests/test_metric.py b/tests/test_metric.py
index 1ed1f90..ccaf0c2 100644
--- a/tests/test_metric.py
+++ b/tests/test_metric.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.metric import MetricRefinement
 from gps_denied.core.models import ModelManager
 from gps_denied.schemas import GPSPoint
diff --git a/tests/test_models.py b/tests/test_models.py
index a927442..8f81832 100644
--- a/tests/test_models.py
+++ b/tests/test_models.py
@@ -1,9 +1,12 @@
 """Tests for Model Manager (F16)."""
 
 import numpy as np
+import pytest
 
 from gps_denied.core.models import ModelManager
 
+pytestmark = [pytest.mark.unit]
+
 
 def test_load_and_get_model():
     manager = ModelManager()
diff --git a/tests/test_pipeline.py b/tests/test_pipeline.py
index 4142bbf..90a56fd 100644
--- a/tests/test_pipeline.py
+++ b/tests/test_pipeline.py
@@ -5,6 +5,8 @@ import cv2
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.pipeline import ImageInputPipeline, QueueFullError
 from gps_denied.schemas.image import ImageBatch
 
diff --git a/tests/test_processor_full.py b/tests/test_processor_full.py
index 369afc6..c53ca77 100644
--- a/tests/test_processor_full.py
+++ b/tests/test_processor_full.py
@@ -5,6 +5,8 @@ from unittest.mock import AsyncMock, MagicMock
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.integration]
+
 from gps_denied.core.chunk_manager import RouteChunkManager
 from gps_denied.core.gpr import GlobalPlaceRecognition
 from gps_denied.core.graph import FactorGraphOptimizer
diff --git a/tests/test_processor_pipe.py b/tests/test_processor_pipe.py
index bc9e45d..8feeb33 100644
--- a/tests/test_processor_pipe.py
+++ b/tests/test_processor_pipe.py
@@ -14,6 +14,8 @@ from unittest.mock import AsyncMock, MagicMock
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.integration]
+
 from gps_denied.core.coordinates import CoordinateTransformer
 from gps_denied.core.processor import FlightProcessor, TrackingState
 from gps_denied.core.rotation import ImageRotationManager
diff --git a/tests/test_recovery.py b/tests/test_recovery.py
index 80224ae..66adb56 100644
--- a/tests/test_recovery.py
+++ b/tests/test_recovery.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.chunk_manager import RouteChunkManager
 from gps_denied.core.gpr import GlobalPlaceRecognition
 from gps_denied.core.graph import FactorGraphOptimizer
diff --git a/tests/test_rotation.py b/tests/test_rotation.py
index a62df91..92531dc 100644
--- a/tests/test_rotation.py
+++ b/tests/test_rotation.py
@@ -5,6 +5,8 @@ from datetime import datetime, timezone
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.rotation import IImageMatcher, ImageRotationManager
 from gps_denied.schemas import GPSPoint
 from gps_denied.schemas.rotation import RotationResult
diff --git a/tests/test_satellite.py b/tests/test_satellite.py
index 2ca0bf7..923716e 100644
--- a/tests/test_satellite.py
+++ b/tests/test_satellite.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.satellite import SatelliteDataManager
 from gps_denied.schemas import GPSPoint
 from gps_denied.utils import mercator
diff --git a/tests/test_schemas.py b/tests/test_schemas.py
index c2654d1..f70c24f 100644
--- a/tests/test_schemas.py
+++ b/tests/test_schemas.py
@@ -3,6 +3,9 @@
 from datetime import datetime, timezone
 
 import pytest
+
+pytestmark = [pytest.mark.unit]
+
 from pydantic import ValidationError
 
 from gps_denied.config import get_settings
diff --git a/tests/test_sitl_integration.py b/tests/test_sitl_integration.py
index d6c387e..7cd8dc0 100644
--- a/tests/test_sitl_integration.py
+++ b/tests/test_sitl_integration.py
@@ -42,10 +42,10 @@ SITL_PORT = int(os.environ.get("ARDUPILOT_SITL_PORT", "5762"))
 
 _SITL_AVAILABLE = bool(SITL_HOST)
 
-pytestmark = pytest.mark.skipif(
+pytestmark = [pytest.mark.sitl, pytest.mark.skipif(
     not _SITL_AVAILABLE,
     reason="SITL integration tests require ARDUPILOT_SITL_HOST env var",
-)
+)]
 
 # ---------------------------------------------------------------------------
 # Helpers
diff --git a/tests/test_vo.py b/tests/test_vo.py
index 9c7dabd..bd7a61a 100644
--- a/tests/test_vo.py
+++ b/tests/test_vo.py
@@ -3,6 +3,8 @@
 import numpy as np
 import pytest
 
+pytestmark = [pytest.mark.unit]
+
 from gps_denied.core.models import ModelManager
 from gps_denied.core.vo import (
     CuVSLAMVisualOdometry,