diff --git a/.gitlab-ci.yml b/.gitlab-ci.yml
index 9fcbab27..63fa0fe1 100644
--- a/.gitlab-ci.yml
+++ b/.gitlab-ci.yml
@@ -24,22 +24,43 @@ variables:
     value: $BLUECONFIGS_BRANCH
     description: 'Name of the blueconfigs branch to test against'
 
-python3-base:
+test-unit:
   extends: .tox-template
   variables:
-    TOXENV: flake8, py3
+    TOXENV: flake8, unit
 
-py38-full-spack:
+test-integration:
   extends: .tox-template
   variables:
-    TOXENV: bb5
+    TOXENV: integration
+
+test-integration-e2e:
+  extends: .tox-template
+  variables:
+    TOXENV: bbp-model
+    TOX_OPTIONS: "-- tests/integration-e2e"
+    # modules need to be loaded in this certain order to avoid mixing of libraries
+    EXTRA_MODULES:
+      unstable:neurodamus-neocortex
+
+test-scientific:
+  extends: .tox-template
+  variables:
+    TOXENV: bbp-model
+    TOX_OPTIONS: "-- tests/scientific"
     # modules need to be loaded in this certain order to avoid mixing of libraries
     EXTRA_MODULES:
-      unstable:py-psutil
       unstable:intel-oneapi-compilers
       unstable:py-bluepy
       unstable:neurodamus-neocortex
-      unstable:py-neurodamus  # needed for dependencies
+
+test-scientific-ngv:
+  extends: .tox-template
+  variables:
+    TOXENV: bbp-model
+    TOX_OPTIONS: "-- tests/scientific-ngv"
+    EXTRA_MODULES:
+      unstable:neurodamus-neocortex-multiscale
 
 set_alt_branches:
   script:
diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index ba1415d3..231906a8 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -22,7 +22,7 @@ to our [GitHub Repository][github]. Even better, you can [submit a Pull Request]
 #  Missing a Feature?
 
 You can *request* a new feature by [submitting an issue](#issues) to our GitHub Repository.
-If you would like to *implement* a new feature, please submit an issue with a proposal for your 
+If you would like to *implement* a new feature, please submit an issue with a proposal for your
 work first, to be sure that we can use it.
 
 Please consider what kind of change it is:
@@ -118,23 +118,65 @@ This section applies to both Python versions 2 and 3.
 
 It is recommended to use `virtualenv` to develop in a sandbox environment:
 
-```
+```sh
 virtualenv venv
 . venv/bin/activate
-pip install -r tests/requirement_tests.txt
+
+# Install neurodamus in development mode
+pip install -e .
+
+# Install test requirements
+pip install -r tests/requirements.txt
+```
+
+## Testing
+
+There are several test groups in Neurodamus, from plain unit tests to integration and system tests.
+
+While developing you may want to run unit tests very frequently and thus we suggest running the base
+tests using pytest directly from the dev environment.
+```sh
+pytest tests/unit
 ```
 
-## Build
+For the next stage testing we suggest using the provided tox environments
 
-Run the following command to build incrementally the project: `pip install -e .`
+```sh
+# Integration tests
+tox -e integration
+```
+
+System and scientific tests require Blue Brain models. They therefore depend on neurodamus-neocortex
+`special` builds and should be launched as follows:
 
-## Test
+```sh
+module load unstable neurodamus-neocortex py-neurodamus
+# Integration-e2e tests
+tox -e bbp-model -- tests/integration-e2e
+
+# Scientific tests
+tox -e bbp-model -- tests/scientific
+```
 
-Run the following command to run the Python unit-tests: `pytest tests`
+### Adding more tests
+
+We kindly ask contributors to add tests alongside their new features or enhancements. With the
+previous setup in mind, consider adding test to one or more groups:
+
+ - `tests/unit`: For unit tests of functions with little dependencies. Tests get a few shared mocks,
+namely for NEURON and MPI.
+ - `tests/integration`: For integration tests. Please place here tests around a component which
+   might depend on a number of functions. Tests here can rely on NEURON and the other base
+   dependencies. Additionally tests are provided a `special` with synapse mechanisms so that
+   Neurodamus can be fully initialized.
+ - `tests/integration-e2e`: Place tests here that require launching a top-level Neurodamus instance.
+   Examples of it might be testing modes of operation, parameter handling, or simply larger
+   integration tests which are validated according to the results.
+ - `tests/scientific[-ngv]`: Should contain tests which validate essential scientific features
+   implemented in Neurodamus, namely creation of synapses, replay, NGV, neurodamulation, etc.
 
 ## Coding conventions
 
 The code coverage of the Python unit-tests may not decrease over time.
 It means that every change must go with their corresponding Python unit-tests to
-validate the library behavior as well as to demonstrate the API usage. 
-
+validate the library behavior as well as to demonstrate the API usage.
diff --git a/ci/build_ndcore.sh b/ci/build_ndcore.sh
index e2545e61..d945288c 100755
--- a/ci/build_ndcore.sh
+++ b/ci/build_ndcore.sh
@@ -12,7 +12,11 @@ fi
 
 # Get the common synapses
 COMMON_DIR=_common
-git clone git@bbpgitlab.epfl.ch:hpc/sim/models/common.git $COMMON_DIR  --depth=1
+if [ -d "$COMMON_DIR" ]; then
+    ( cd "$COMMON_DIR" && git pull --quiet )
+else
+    git clone git@bbpgitlab.epfl.ch:hpc/sim/models/common.git $COMMON_DIR  --depth=1
+fi
 
 MOD_BUILD_DIR="mods.tmp"
 mkdir -p $MOD_BUILD_DIR
diff --git a/setup.cfg b/setup.cfg
index 14c8b0ea..a411c76d 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -17,7 +17,7 @@ classifier =
     License :: Other/Proprietary License
 
 [tool:pytest]
-addopts = tests --verbose
+addopts = --verbose
 markers = slow: marks tests as slow
 
 [aliases]
@@ -36,6 +36,6 @@ formats = bdist_wheel
 
 [flake8]
 exclude = .*, __pycache__, .eggs, *.egg, build, dist, docs, venv, *.egg-info, _benchmarks, core
-ignore = E127, E221, E226, E701, W503, W504, E731
+ignore = E127, E221, E226, E701, W503, W504, E731, PT001, PT023
 max-line-length = 100
 # max-complexity = 12
diff --git a/tests/conftest.py b/tests/conftest.py
index aa56191d..ad4bf464 100644
--- a/tests/conftest.py
+++ b/tests/conftest.py
@@ -4,6 +4,16 @@
 USECASE3 = Path(__file__).parent.absolute() / "simulations" / "usecase3"
 
 
+@pytest.fixture(scope="session")
+def rootdir(request):
+    return request.config.rootdir
+
+
+@pytest.fixture(scope="session", name="USECASE3")
+def usecase3_path():
+    return USECASE3
+
+
 @pytest.fixture
 def sonata_config():
     return dict(
diff --git a/tests/integration-e2e/conftest.py b/tests/integration-e2e/conftest.py
new file mode 100644
index 00000000..7cea024d
--- /dev/null
+++ b/tests/integration-e2e/conftest.py
@@ -0,0 +1,8 @@
+import os
+import pytest
+
+assert os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"), "Test requires loading a neocortex model to run"
+
+pytestmark = [
+    pytest.mark.forked,
+]
diff --git a/tests/test_cli_opts.py b/tests/integration-e2e/test_cli_opts.py
similarity index 86%
rename from tests/test_cli_opts.py
rename to tests/integration-e2e/test_cli_opts.py
index 53d7ff23..5d3d8249 100644
--- a/tests/test_cli_opts.py
+++ b/tests/integration-e2e/test_cli_opts.py
@@ -1,5 +1,4 @@
 import json
-import os
 from pathlib import Path
 import pytest
 import shutil
@@ -7,14 +6,11 @@
 import tempfile
 
 
-SIM_DIR = Path(__file__).parent.absolute() / "simulations" / "v5_sonata"
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations" / "v5_sonata"
 CONFIG_FILE_MINI = "simulation_config_mini.json"
 
 
 @pytest.mark.slow
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_save_restore_cli():
     with open(SIM_DIR / CONFIG_FILE_MINI, "r") as f:
         sim_config_data = json.load(f)
@@ -47,9 +43,6 @@ def test_save_restore_cli():
                 subprocess.run(command, check=True)
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_cli_prcellgid():
     test_folder = tempfile.TemporaryDirectory("cli-test-prcellgid")  # auto removed
     test_folder_path = Path(test_folder.name)
diff --git a/tests/test_connection.py b/tests/integration-e2e/test_connection.py
similarity index 81%
rename from tests/test_connection.py
rename to tests/integration-e2e/test_connection.py
index 67a2cf9a..fa075a88 100644
--- a/tests/test_connection.py
+++ b/tests/integration-e2e/test_connection.py
@@ -1,18 +1,14 @@
-import os
 import pytest
 from pathlib import Path
 from neurodamus.io.synapse_reader import SynapseParameters
 from neurodamus.node import Node
 
 
-SIM_DIR = Path(__file__).parent.absolute() / "simulations" / "v5_sonata"
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations" / "v5_sonata"
 CONFIG_FILE_MINI = SIM_DIR / "simulation_config_mini.json"
 
 
 @pytest.mark.slow
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 # This test is to mimic the error reported in HPCTM-1687 during connection.add_syanpses()
 # when detecting conn._synapse_params with more than one element is not None
 def test_add_synapses():
diff --git a/tests/integration-e2e/test_dry_run_worflow.py b/tests/integration-e2e/test_dry_run_worflow.py
new file mode 100644
index 00000000..cdd217b7
--- /dev/null
+++ b/tests/integration-e2e/test_dry_run_worflow.py
@@ -0,0 +1,25 @@
+
+def test_dry_run_workflow(USECASE3):
+    """
+    Test that the dry run mode works
+    """
+
+    from neurodamus import Neurodamus
+    nd = Neurodamus(
+        str(USECASE3 / "simulation_sonata.json"),
+        dry_run=True
+    )
+
+    nd.run()
+
+    assert 20.0 <= nd._dry_run_stats.cell_memory_total <= 30.0
+    assert 0.0 <= nd._dry_run_stats.synapse_memory_total <= 1.0
+    assert 80.0 <= nd._dry_run_stats.base_memory <= 120.0
+    expected_items = {
+        'L4_PC-dSTUT': 2,
+        'L4_MC-dSTUT': 1,
+        'L4_MC-dNAC': 1,
+        'L5_PC-dSTUT': 1
+    }
+    assert nd._dry_run_stats.metype_counts == expected_items
+    assert nd._dry_run_stats.suggest_nodes(0.3) > 0
diff --git a/tests/test_error_handling.py b/tests/integration-e2e/test_error_handling.py
similarity index 51%
rename from tests/test_error_handling.py
rename to tests/integration-e2e/test_error_handling.py
index dbdf7d4b..27c10cfc 100644
--- a/tests/test_error_handling.py
+++ b/tests/integration-e2e/test_error_handling.py
@@ -1,21 +1,8 @@
-import os
 import pytest
-from pathlib import Path
 
 
-USECASE3 = Path(__file__).parent.absolute() / "simulations" / "usecase3"
-SONATA_CONF_FILE = str(USECASE3 / "simulation_sonata.json")
-
-pytestmark = [
-    pytest.mark.forked,
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run"
-    )
-]
-
-
-def test_handling_neuron_exceptions():
+def test_handling_neuron_exceptions(USECASE3):
+    SONATA_CONF_FILE = str(USECASE3 / "simulation_sonata.json")
     from neurodamus import Node
     n = Node(SONATA_CONF_FILE)
     n.load_targets()
diff --git a/tests/test_loadbalance.py b/tests/integration-e2e/test_loadbalance.py
similarity index 93%
rename from tests/test_loadbalance.py
rename to tests/integration-e2e/test_loadbalance.py
index 39e58599..4fa375c8 100644
--- a/tests/test_loadbalance.py
+++ b/tests/integration-e2e/test_loadbalance.py
@@ -1,3 +1,5 @@
+"""Tests load balance."""
+# Since a good deal of load balance tests are e2e we put all of them together in this group
 import logging
 import os
 import pytest
@@ -5,9 +7,7 @@
 import tempfile
 from pathlib import Path
 
-SIM_DIR = Path(__file__).parent.absolute() / "simulations"
-
-pytestmark = pytest.mark.forked
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations"
 
 
 @pytest.fixture
@@ -69,10 +69,6 @@ def circuit_conf():
     )
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 def test_load_balance_integrated(target_manager_hoc, circuit_conf):
     """Comprehensive test using real cells and deriving cx for a sub-target
     """
@@ -102,10 +98,6 @@ def test_load_balance_integrated(target_manager_hoc, circuit_conf):
     assert not lbal._reuse_cell_complexity(TargetSpec(None))
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 def test_multisplit(target_manager_hoc, circuit_conf, capsys):
     """Comprehensive test using real cells, multi-split and complexity derivation
     """
@@ -146,10 +138,6 @@ def test_multisplit(target_manager_hoc, circuit_conf, capsys):
     assert "Target VerySmall is a subset of the target Small" in captured.out
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 def test_loadbal_integration():
     """Ensure given the right files are in the lbal dir, the correct situation is detected
     """
diff --git a/tests/test_multicycle_runs.py b/tests/integration-e2e/test_multicycle_runs.py
similarity index 87%
rename from tests/test_multicycle_runs.py
rename to tests/integration-e2e/test_multicycle_runs.py
index adbd3d1b..c44d2de0 100644
--- a/tests/test_multicycle_runs.py
+++ b/tests/integration-e2e/test_multicycle_runs.py
@@ -3,18 +3,14 @@
 import pytest
 from pathlib import Path
 
-SIM_DIR = Path(__file__).parent.absolute() / "simulations"
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations"
 
 
 @pytest.fixture(autouse=True)
-def change_test_dir(monkeypatch, tmp_path):
+def _change_test_dir(monkeypatch, tmp_path):
     monkeypatch.chdir(str(SIM_DIR / "usecase3"))
 
 
-@pytest.mark.forked
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test initialize internal structure and clashes with other tests")
 def test_nodeset_target_generate_subtargets():
     from neurodamus.core.nodeset import NodeSet
     from neurodamus.target_manager import NodesetTarget
@@ -45,10 +41,6 @@ def test_nodeset_target_generate_subtargets():
     assert np.array_equal(subtargets[2][1].get_gids(), np.array([1002]))
 
 
-@pytest.mark.forked
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test initialize internal structure and clashes with other tests")
 def test_hoc_target_generate_subtargets():
     from neurodamus.target_manager import _HocTarget
 
@@ -94,10 +86,6 @@ def _read_sonata_spike_file(spike_file):
     return timestamps, spike_gids
 
 
-@pytest.mark.forked
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_v5_sonata_multisteps():
     import numpy.testing as npt
     from neurodamus import Neurodamus
@@ -126,10 +114,6 @@ def test_v5_sonata_multisteps():
     npt.assert_allclose(timestamps, obtained_timestamps)
 
 
-@pytest.mark.forked
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_usecase3_sonata_multisteps():
     import numpy.testing as npt
     from neurodamus import Neurodamus
diff --git a/tests/test_plugin.py b/tests/integration-e2e/test_plugin.py
similarity index 98%
rename from tests/test_plugin.py
rename to tests/integration-e2e/test_plugin.py
index 339f5ba9..fc38010c 100644
--- a/tests/test_plugin.py
+++ b/tests/integration-e2e/test_plugin.py
@@ -20,7 +20,7 @@
 #
 # Launching of the engine as a test
 #
-SIM_DIR = Path(__file__).parent.absolute() / "simulations"
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations"
 
 
 class ACellType(BaseCell):
diff --git a/tests/test_synapse_reader.py b/tests/integration-e2e/test_synapse_reader.py
similarity index 87%
rename from tests/test_synapse_reader.py
rename to tests/integration-e2e/test_synapse_reader.py
index b44d3feb..7ce7b5c1 100644
--- a/tests/test_synapse_reader.py
+++ b/tests/integration-e2e/test_synapse_reader.py
@@ -1,18 +1,9 @@
 import numpy as np
 import numpy.testing as npt
-import os
-import pytest
 from neurodamus.gap_junction import GapJunctionSynapseReader
 from pathlib import Path
 
-
-pytestmark = [
-    pytest.mark.forked,
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run"
-    )
-]
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations"
 
 
 def test_gapjunction_synreaderNRN():
@@ -35,7 +26,6 @@ def test_gapjunction_synreaderNRN():
 
 
 def test_gapjunction_sonata_reader():
-    SIM_DIR = Path(__file__).parent.absolute() / "simulations"
     sonata_file = str(SIM_DIR / "mini_thalamus_sonata/gapjunction/edges.h5")
     sonata_reader = GapJunctionSynapseReader.create(sonata_file, 1)
     syn_params_sonata = sonata_reader._load_synapse_parameters(1)
diff --git a/tests/integration/conftest.py b/tests/integration/conftest.py
new file mode 100644
index 00000000..8671132a
--- /dev/null
+++ b/tests/integration/conftest.py
@@ -0,0 +1,6 @@
+import pytest
+# !! NOTE: Please don't import NEURON/Neurodamus at module level
+# pytest weird discovery system will trigger NEURON init and open a can of worms
+
+# Make all tests run forked
+pytestmark = pytest.mark.forked
diff --git a/tests/test_cell.py b/tests/integration/test_cell.py
similarity index 84%
rename from tests/test_cell.py
rename to tests/integration/test_cell.py
index a2c0bb98..92176741 100644
--- a/tests/test_cell.py
+++ b/tests/integration/test_cell.py
@@ -1,17 +1,21 @@
 """
 Basic tests to HL neuron for creating cells and setup a simple simulation
 """
-from os import path
+import os
 import pytest
-
+from pathlib import Path
 # !! NOTE: Please don't import neron/neurodamus at module level
 # pytest weird discovery system will trigger Neuron init and open can of worms
-# And make all tests run forked
-pytestmark = pytest.mark.forked
+
+
+@pytest.fixture(scope="session")
+def morphologies_root(rootdir):
+    return Path(rootdir) / "tests/sample_data/morphology"
 
 
 @pytest.fixture
-def Cell():
+def Cell(rootdir):
+    os.environ["HOC_LIBRARY_PATH"] = str(rootdir) + "/core/hoc"
     from neurodamus.core import Cell
     return Cell
 
@@ -20,20 +24,15 @@ def Cell():
     "morphology_path",
     ["C060114A7.asc", "C060114A7.h5", "merged_container.h5/C060114A7.h5"]
 )
-def test_load_cell(morphology_path, request):
-    Cell = request.getfixturevalue("Cell")
-
-    d = path.dirname(__file__)
-    c = Cell(1, path.join(d, "morphology", morphology_path))
+def test_load_cell(morphologies_root, morphology_path, Cell):
+    c = Cell(1, str(morphologies_root / morphology_path))
     assert len(c.all) == 325
     assert c.axons[4].name().endswith(".axon[4]")
     assert c.soma.L == pytest.approx(26.11, abs=0.01)
 
 
-def test_morphio_read(Cell):
-    d = path.dirname(__file__)
-    c = Cell(1, path.join(d, "morphology/simple.h5"))
-
+def test_morphio_read(morphologies_root, Cell):
+    c = Cell(1, str(morphologies_root / "simple.h5"))
     Cell.show_topology()
     assert len(c.all) == 7
     assert len(list(c.h.basal)) == 3
diff --git a/tests/test_neuron.py b/tests/integration/test_neuron.py
similarity index 100%
rename from tests/test_neuron.py
rename to tests/integration/test_neuron.py
diff --git a/tests/test_sonata_config.py b/tests/integration/test_sonata_config.py
similarity index 98%
rename from tests/test_sonata_config.py
rename to tests/integration/test_sonata_config.py
index 988ad21b..0b100442 100644
--- a/tests/test_sonata_config.py
+++ b/tests/integration/test_sonata_config.py
@@ -3,7 +3,7 @@
 from pathlib import Path
 from tempfile import NamedTemporaryFile
 
-USECASE3 = Path(__file__).parent.absolute() / "simulations" / "usecase3"
+USECASE3 = Path(__file__).parent.parent.absolute() / "simulations" / "usecase3"
 SONATA_CONF_FILE = str(USECASE3 / "simulation_sonata.json")
 
 pytestmark = pytest.mark.forked
diff --git a/tests/test_sonata_output.py b/tests/integration/test_sonata_output.py
similarity index 71%
rename from tests/test_sonata_output.py
rename to tests/integration/test_sonata_output.py
index bd0c7000..c203d199 100644
--- a/tests/test_sonata_output.py
+++ b/tests/integration/test_sonata_output.py
@@ -2,19 +2,12 @@
 import json
 import pytest
 from tempfile import NamedTemporaryFile
-from neurodamus.node import Node
 
 pytestmark = pytest.mark.forked  # independent processes
 
 
-# Currently exclude this test from base tests because of failure,
-# perhaps NEURON and log file has been initialised by some unforked test.
-# TODO: Review our unit tests with marker pytest.mark.slow
-# so as to exclude them from base tests by pytest -m "not slow"
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_sonata_logfile(sonata_config):
+    from neurodamus.node import Node
     sonata_config["output"] = {"log_file": "my_pydamus.log"}
     # create a tmp json file to test the user defined log_file
     with NamedTemporaryFile("w", suffix=".json", delete=False) as config_file:
@@ -26,6 +19,7 @@ def test_sonata_logfile(sonata_config):
 
 
 def test_throw_spike_sort_order(sonata_config):
+    from neurodamus.node import Node
     from neurodamus.core.configuration import ConfigurationError
 
     sonata_config["output"] = {"spikes_sort_order": "by_id"}
diff --git a/tests/test_stimuli.py b/tests/integration/test_stimulus2.py
similarity index 65%
rename from tests/test_stimuli.py
rename to tests/integration/test_stimulus2.py
index 90373c9d..b201818d 100644
--- a/tests/test_stimuli.py
+++ b/tests/integration/test_stimulus2.py
@@ -1,7 +1,7 @@
-#!/usr/bin/env python
 """
-Test suite for the new-gen Stimuli source (replacing TStim.hoc and parts of StimManager)
+A collection of tests for advanced stimulus generated with the help of Neuron
 """
+
 import pytest
 from neurodamus.core import CurrentSource, ConductanceSource
 from neurodamus.core.random import Random123
@@ -12,48 +12,6 @@ def setup_method(self):
         rng = Random123(1, 2, 3)
         self.stim = CurrentSource(rng=rng)
 
-    def test_flat_segment(self):
-        self.stim.add_segment(1.2, 10)
-        assert list(self.stim.time_vec) == [0, 10]
-        assert list(self.stim.stim_vec) == [1.2, 1.2]
-
-    def test_pulse(self):
-        self.stim.add_pulse(1.2, 10)
-        assert list(self.stim.time_vec) == [0, 0, 10, 10]
-        assert list(self.stim.stim_vec) == [0, 1.2, 1.2, 0]
-
-    @pytest.mark.parametrize("base_amp", [-1, 0, 1.5])
-    def test_pulse_diff_base(self, base_amp):
-        self.stim.add_pulse(1.2, 10, base_amp=base_amp)
-        assert list(self.stim.time_vec) == [0, 0, 10, 10]
-        assert list(self.stim.stim_vec) == [base_amp, 1.2, 1.2, base_amp]
-
-    def test_two_pulses(self):
-        self.stim.add_pulse(1.2, 10)
-        self.stim.delay(5)
-        self.stim.add_pulse(0.8, 5)
-        assert list(self.stim.time_vec) == [0, 0, 10, 10, 15, 15, 20, 20]
-        assert list(self.stim.stim_vec) == [0, 1.2, 1.2, 0, 0, 0.8, 0.8, 0]
-
-    def test_ramp(self):
-        self.stim.add_ramp(5, 7.5, 10)
-        assert list(self.stim.time_vec) == [0, 0, 10, 10]
-        assert list(self.stim.stim_vec) == [0, 5, 7.5, 0]
-
-    def test_delay_ramp(self):
-        # When a delay is specified (in ctor or factory) base_amp is set on t=0 too
-        sig = CurrentSource.ramp(1, 2, 2, base_amp=-1, delay=10)
-        assert list(sig.time_vec) == [0, 10, 10, 12, 12]
-        assert list(sig.stim_vec) == [-1, -1, 1, 2, -1]
-
-    def test_train(self):
-        self.stim.add_train(1.2, 10, 20, 350)
-        # At 10Hz pulses have T=100ms
-        # We end up with 4 pulses, the last one with reduced rest phase
-        assert list(self.stim.time_vec) == [0, 0, 20, 20, 100, 100, 120, 120, 200, 200, 220, 220,
-                                            300, 300, 320, 320, 350]
-        assert list(self.stim.stim_vec) == [0, 1.2, 1.2, 0] * 4 + [0]
-
     def test_sin(self):
         self.stim.add_sin(1, 0.1, 10000)
         assert list(self.stim.time_vec) == pytest.approx([0, 0.025, 0.05, 0.075, 0.1, 0.1])
diff --git a/tests/requirements.txt b/tests/requirements.txt
new file mode 100644
index 00000000..df609324
--- /dev/null
+++ b/tests/requirements.txt
@@ -0,0 +1,3 @@
+pytest==7.4
+pytest-forked==1.6
+scipy==1.10
diff --git a/tests/morphology/C060114A7.asc b/tests/sample_data/morphology/C060114A7.asc
similarity index 100%
rename from tests/morphology/C060114A7.asc
rename to tests/sample_data/morphology/C060114A7.asc
diff --git a/tests/morphology/C060114A7.h5 b/tests/sample_data/morphology/C060114A7.h5
similarity index 100%
rename from tests/morphology/C060114A7.h5
rename to tests/sample_data/morphology/C060114A7.h5
diff --git a/tests/morphology/merged_container.h5 b/tests/sample_data/morphology/merged_container.h5
similarity index 100%
rename from tests/morphology/merged_container.h5
rename to tests/sample_data/morphology/merged_container.h5
diff --git a/tests/morphology/simple.h5 b/tests/sample_data/morphology/simple.h5
similarity index 100%
rename from tests/morphology/simple.h5
rename to tests/sample_data/morphology/simple.h5
diff --git a/tests/scientific-ngv/conftest.py b/tests/scientific-ngv/conftest.py
new file mode 100644
index 00000000..7cea024d
--- /dev/null
+++ b/tests/scientific-ngv/conftest.py
@@ -0,0 +1,8 @@
+import os
+import pytest
+
+assert os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"), "Test requires loading a neocortex model to run"
+
+pytestmark = [
+    pytest.mark.forked,
+]
diff --git a/tests/test_ngv.py b/tests/scientific-ngv/test_ngv.py
similarity index 61%
rename from tests/test_ngv.py
rename to tests/scientific-ngv/test_ngv.py
index 24e33fa6..e003cac3 100644
--- a/tests/test_ngv.py
+++ b/tests/scientific-ngv/test_ngv.py
@@ -1,66 +1,14 @@
 """
 Test suite for Neurodamus NGV support
 """
-import os
-import subprocess
 from pathlib import Path
 
 import libsonata
 import numpy as np
-import pytest
 
-from neurodamus import Neurodamus
-from neurodamus.ngv import GlioVascularManager
-
-SIM_DIR = Path(__file__).parent.absolute() / "simulations" / "ngv"
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations" / "ngv"
 SONATACONFIG_FILE = SIM_DIR / "simulation_config.json"
 
-pytestmark = [
-    pytest.mark.forked,
-    pytest.mark.slow,
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run",
-    ),
-]
-
-
-def load_neurodamus_neocortex_multiscale():
-    module_output = subprocess.run(
-        ["module load unstable; module show neurodamus-neocortex-multiscale"],
-        capture_output=True,
-        text=True,
-        shell=True,
-    )
-    nrn_mech_path = None
-    ld_library_path = None
-    for line in module_output.stderr.split("\n"):
-        if "NRNMECH_LIB_PATH" in line:
-            nrn_mech_path = line.split(" ")[2]
-            ld_library_path = os.path.dirname(nrn_mech_path)
-    if nrn_mech_path is not None:
-        os.environ["NRNMECH_LIB_PATH"] = nrn_mech_path
-        os.environ["LD_LIBRARY_PATH"] = (
-            ld_library_path + ":" + os.environ.get("LD_LIBRARY_PATH", "")
-        )
-    else:
-        module_output = subprocess.run(
-            ["module load unstable; module show neurodamus-neocortex"],
-            capture_output=True,
-            text=True,
-            shell=True,
-        )
-        raise Exception(
-            "Right module not found. Output of 'module av neurodamus-neocortex': {}\n"
-            "MODULEPATH: {}".format(module_output.stderr, os.environ.get("MODULEPATH"))
-        )
-
-
-def get_manager(ndamus):
-    return ndamus.circuits.get_edge_manager(
-        "vasculature", "astrocytes", GlioVascularManager
-    )
-
 
 def get_R0pas(astro_id, manager):
     astrocyte = manager._cell_manager.gid2cell[astro_id + manager._gid_offset]
@@ -99,7 +47,8 @@ def get_R0pas_ref(astro_id, manager):
 
 
 def test_vasccouplingB_radii():
-    load_neurodamus_neocortex_multiscale()
+    from neurodamus import Neurodamus
+    from neurodamus.ngv import GlioVascularManager
     ndamus = Neurodamus(
         str(SONATACONFIG_FILE),
         enable_reports=False,
@@ -107,7 +56,7 @@ def test_vasccouplingB_radii():
         enable_coord_mapping=True,
     )
 
-    manager = get_manager(ndamus)
+    manager = ndamus.circuits.get_edge_manager("vasculature", "astrocytes", GlioVascularManager)
     astro_ids = manager._astro_ids
 
     R0pas = [r for astro_id in astro_ids for r in get_R0pas(astro_id, manager)]
diff --git a/tests/scientific/conftest.py b/tests/scientific/conftest.py
new file mode 100644
index 00000000..eb991fd6
--- /dev/null
+++ b/tests/scientific/conftest.py
@@ -0,0 +1,11 @@
+import os
+import pytest
+
+assert os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"), \
+    "Test requires loading a neocortex model to run"
+assert os.path.isfile("/gpfs/bbp.cscs.ch/project/proj83/circuits/Bio_M/20200805/circuit.mvd3"), \
+    "Circuit file not available"
+
+pytestmark = [
+    pytest.mark.forked,
+]
diff --git a/tests/scientific/test_dry_run_worflow.py b/tests/scientific/test_dry_run_worflow.py
deleted file mode 100644
index a714ccb4..00000000
--- a/tests/scientific/test_dry_run_worflow.py
+++ /dev/null
@@ -1,34 +0,0 @@
-import os
-import pytest
-from pathlib import Path
-from collections import Counter
-
-USECASE3 = Path(__file__).parent.absolute() / "usecase3"
-
-
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
-def test_dry_run_workflow():
-    """
-    Test that the dry run mode works
-    """
-
-    from neurodamus import Neurodamus
-    nd = Neurodamus(
-        str(USECASE3 / "simulation_sonata.json"),
-        dry_run=True
-    )
-
-    nd.run()
-
-    assert 20.0 <= nd._dry_run_stats.cell_memory_total <= 30.0
-    assert 0.0 <= nd._dry_run_stats.synapse_memory_total <= 1.0
-    assert 90.0 <= nd._dry_run_stats.base_memory <= 120.0
-    expected_items = Counter([('L4_PC-dSTUT', 2),
-                              ('L4_MC-dSTUT', 1),
-                              ('L4_MC-dNAC', 1),
-                              ('L5_PC-dSTUT', 1)])
-    assert set(nd._dry_run_stats.metype_counts.items()) == set(expected_items)
-    assert nd._dry_run_stats.suggest_nodes(0.3) > 0
diff --git a/tests/test_lfp.py b/tests/scientific/test_lfp.py
similarity index 93%
rename from tests/test_lfp.py
rename to tests/scientific/test_lfp.py
index 70bc6faf..50115435 100644
--- a/tests/test_lfp.py
+++ b/tests/scientific/test_lfp.py
@@ -4,16 +4,7 @@
 import numpy as np
 from pathlib import Path
 
-SIM_DIR = Path(__file__).parent.absolute() / "simulations"
-
-pytestmark = [
-    pytest.mark.forked,
-    pytest.mark.slow,
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run"
-    )
-]
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations"
 
 
 @pytest.fixture
@@ -61,7 +52,7 @@ def test_file(tmpdir):
             incrementy -= 0.0032
         electrodes_group.create_dataset("scaling_factors", dtype='f8', data=matrix)
 
-    yield test_file
+    return test_file
 
 
 def test_load_lfp_config(tmpdir, test_file):
@@ -167,10 +158,6 @@ def _read_sonata_lfp_file(lfp_file):
     return node_ids, data
 
 
-@pytest.mark.forked
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_v5_sonata_lfp(tmpdir, test_file):
     import numpy.testing as npt
     from neurodamus import Neurodamus
diff --git a/tests/test_modification.py b/tests/scientific/test_modification.py
similarity index 92%
rename from tests/test_modification.py
rename to tests/scientific/test_modification.py
index 31bf28c0..0c073a0e 100644
--- a/tests/test_modification.py
+++ b/tests/scientific/test_modification.py
@@ -83,19 +83,6 @@
 }
 """
 
-pytestmark = [
-    pytest.mark.slow,
-    pytest.mark.forked,
-    pytest.mark.skipif(
-        not os.path.isfile("/gpfs/bbp.cscs.ch/project/proj83/circuits/Bio_M/20200805/circuit.mvd3"),
-        reason="Circuit file not available"
-    ),
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run"
-    )
-]
-
 
 @pytest.fixture(scope="module")
 def blueconfig():
@@ -153,7 +140,8 @@ def test_TTX_modification(blueconfig):
     nspike_TTX = sum(len(spikes) for spikes, _ in n._spike_vecs)
 
     log_verbose("spikes without TTX = %s, with TTX = %s", nspike_noTTX, nspike_TTX)
-    assert (nspike_noTTX > 0 and nspike_TTX == 0)
+    assert nspike_noTTX > 0
+    assert nspike_TTX == 0
 
 
 def test_ConfigureAllSections_modification(blueconfig):
diff --git a/tests/scientific/test_multipop.py b/tests/scientific/test_multipop.py
index 5cdb01ea..1b4ce1ee 100644
--- a/tests/scientific/test_multipop.py
+++ b/tests/scientific/test_multipop.py
@@ -35,10 +35,6 @@ def sonata_config_file(sonata_config, extra_config):
     os.unlink(config_file.name)
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 @pytest.mark.parametrize("extra_config", [{
     "connection_overrides": [
         {
@@ -82,18 +78,16 @@ def test_multipop_simple(sonata_config_file):
     assert set(cell_man.local_nodes.final_gids()) == set(cell_man.gid2cell) == {1001, 1002}
 
     for conn in edges_A.all_connections():
-        assert conn.tgid <= 3 and conn.sgid <= 3
+        assert conn.tgid <= 3
+        assert conn.sgid <= 3
         assert conn.synapses[0].verboseLevel == 0
 
     for conn in edges_B.all_connections():
-        assert 1000 < conn.tgid <= 1003 and 1000 < conn.sgid <= 1003
+        assert 1000 < conn.tgid <= 1003
+        assert 1000 < conn.sgid <= 1003
         assert conn.synapses[0].verboseLevel == 1
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 @pytest.mark.parametrize("extra_config", [{
     "connection_overrides": [
         {
@@ -159,19 +153,23 @@ def test_multipop_full_conn(sonata_config_file):
     assert edges_BA.src_cell_manager == cell_man_B
 
     for conn in edges_A.all_connections():
-        assert conn.tgid <= 3 and conn.sgid <= 3
+        assert conn.tgid <= 3
+        assert conn.sgid <= 3
         assert conn.synapses[0].verboseLevel == 0
 
     for conn in edges_B.all_connections():
-        assert 1000 < conn.tgid <= 1003 and 1000 < conn.sgid <= 1003
+        assert 1000 < conn.tgid <= 1003
+        assert 1000 < conn.sgid <= 1003
         assert conn.synapses[0].verboseLevel == 1
 
     for conn in edges_BA.all_connections():
-        assert 0 < conn.tgid <= 3 and 1000 < conn.sgid <= 1003
+        assert 0 < conn.tgid <= 3
+        assert 1000 < conn.sgid <= 1003
         assert conn.synapses[0].verboseLevel == 2
 
     for conn in edges_AB.all_connections():
-        assert 1000 < conn.tgid <= 1003 and 0 < conn.sgid <= 3
+        assert 1000 < conn.tgid <= 1003
+        assert 0 < conn.sgid <= 3
         assert conn.synapses[0].verboseLevel == 3
 
     # Replay will create spikes for all instantiated cells targeting popA
diff --git a/tests/test_neuromodulation.py b/tests/scientific/test_neuromodulation.py
similarity index 78%
rename from tests/test_neuromodulation.py
rename to tests/scientific/test_neuromodulation.py
index aa73c645..c9c53f23 100644
--- a/tests/test_neuromodulation.py
+++ b/tests/scientific/test_neuromodulation.py
@@ -1,23 +1,15 @@
 import numpy as np
 import numpy.testing as npt
 import os
-import pytest
 from pathlib import Path
 
-pytestmark = [
-    pytest.mark.forked,
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run"
-    )
-]
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations" / "neuromodulation"
 
 
 def test_neuromodulation_sims_neuron():
     import numpy.testing as npt
     from neurodamus import Neurodamus
 
-    SIM_DIR = Path(__file__).parent.absolute() / "simulations" / "neuromodulation"
     config_file = str(SIM_DIR / "BlueConfig")
     os.chdir(SIM_DIR)
     nd = Neurodamus(config_file, disable_reports=True)
@@ -32,12 +24,10 @@ def test_neuromodulation_sims_neuron():
     npt.assert_allclose(timestamps, obtained_timestamps)
 
 
-@pytest.mark.forked
 def test_neuromodulation_sims_coreneuron():
     from neurodamus import Neurodamus
     from neurodamus.replay import SpikeManager
 
-    SIM_DIR = Path(__file__).parent.absolute() / "simulations" / "neuromodulation"
     config_file = str(SIM_DIR / "BlueConfig")
     os.chdir(SIM_DIR)
     nd = Neurodamus(config_file, disable_reports=True, simulator="CORENEURON",
diff --git a/tests/test_patched_delays.py b/tests/scientific/test_patched_delays.py
similarity index 92%
rename from tests/test_patched_delays.py
rename to tests/scientific/test_patched_delays.py
index 9e370dd5..41517f21 100644
--- a/tests/test_patched_delays.py
+++ b/tests/scientific/test_patched_delays.py
@@ -72,13 +72,6 @@
 
 
 @pytest.mark.slow
-@pytest.mark.forked
-@pytest.mark.skipif(
-    not os.path.isfile("/gpfs/bbp.cscs.ch/project/proj83/circuits/Bio_M/20200805/circuit.mvd3"),
-    reason="Circuit file not available")
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_eager_caching():
     """
     A test of the impact of eager caching of synaptic parameters. BBPBGLIB-813
diff --git a/tests/scientific/test_projections.py b/tests/scientific/test_projections.py
index 1d5ca9f6..a3c99692 100644
--- a/tests/scientific/test_projections.py
+++ b/tests/scientific/test_projections.py
@@ -45,10 +45,6 @@ def sonata_config_file(sonata_config):
     os.unlink(config_file.name)
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 def test_projections(sonata_config_file):
     """
     Test that projections are correctly set up
diff --git a/tests/scientific/test_replay.py b/tests/scientific/test_replay.py
index 1e4e3748..4f3eb5b7 100644
--- a/tests/scientific/test_replay.py
+++ b/tests/scientific/test_replay.py
@@ -2,7 +2,6 @@
 import numpy
 import numpy.testing as npt
 import os
-import pytest
 from pathlib import Path
 from tempfile import NamedTemporaryFile
 
@@ -29,10 +28,6 @@ def replay_sim_config(sonata_config, replay_file):
     return config_file
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 def test_replay_sim(sonata_config):
     from neurodamus import Neurodamus
     from neurodamus.core.configuration import Feature
@@ -74,10 +69,6 @@ def test_replay_sim(sonata_config):
 
 # A more comprehensive example, using Sonata replay with two populations
 # ======================================================================
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 def test_replay_sonata_spikes(sonata_config):
     from neurodamus import Neurodamus
     from neurodamus.core.configuration import Feature
diff --git a/tests/test_simulation.py b/tests/scientific/test_simulation.py
similarity index 94%
rename from tests/test_simulation.py
rename to tests/scientific/test_simulation.py
index a794cfb8..b590541c 100644
--- a/tests/test_simulation.py
+++ b/tests/scientific/test_simulation.py
@@ -5,16 +5,7 @@
 import subprocess
 from pathlib import Path
 
-SIM_DIR = Path(__file__).parent.absolute() / "simulations"
-
-pytestmark = [
-    pytest.mark.forked,
-    pytest.mark.slow,
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run"
-    )
-]
+SIM_DIR = Path(__file__).parent.parent.absolute() / "simulations"
 
 
 @pytest.mark.skipif(
diff --git a/tests/test_sonata_properties.py b/tests/scientific/test_sonata_properties.py
similarity index 95%
rename from tests/test_sonata_properties.py
rename to tests/scientific/test_sonata_properties.py
index 44146853..791ec520 100644
--- a/tests/test_sonata_properties.py
+++ b/tests/scientific/test_sonata_properties.py
@@ -98,20 +98,6 @@
 }
 """
 
-# Prerequisites
-pytestmark = [
-    pytest.mark.slow,
-    pytest.mark.forked,
-    pytest.mark.skipif(
-        not os.path.isfile(NODE),
-        reason="Circuit file not available"
-    ),
-    pytest.mark.skipif(
-        not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-        reason="Test requires loading a neocortex model to run"
-    )
-]
-
 
 @pytest.fixture(scope="module")
 def blueconfig():
diff --git a/tests/scientific/test_spont_minis.py b/tests/scientific/test_spont_minis.py
index e3554fd8..49d8bbf0 100644
--- a/tests/scientific/test_spont_minis.py
+++ b/tests/scientific/test_spont_minis.py
@@ -31,10 +31,6 @@ def sonata_config_file(sonata_config):
     os.unlink(config_file.name)
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run"
-)
 def test_spont_minis(sonata_config_file):
     from neurodamus.connection_manager import Nd, SynapseRuleManager
     from neurodamus import Neurodamus
diff --git a/tests/test_synapses.py b/tests/scientific/test_synapses.py
similarity index 95%
rename from tests/test_synapses.py
rename to tests/scientific/test_synapses.py
index cb4bc906..4341eeaa 100644
--- a/tests/test_synapses.py
+++ b/tests/scientific/test_synapses.py
@@ -5,6 +5,7 @@
 from pathlib import Path
 from tempfile import NamedTemporaryFile
 
+USECASE3 = Path(__file__).parent.parent.absolute() / "simulations" / "usecase3"
 
 # BlueConfig string
 BC_str = """
@@ -106,13 +107,6 @@ def blueconfig1():
 
 
 @pytest.mark.slow
-@pytest.mark.forked
-@pytest.mark.skipif(
-    not os.path.isfile("/gpfs/bbp.cscs.ch/project/proj83/circuits/Bio_M/20200805/circuit.mvd3"),
-    reason="Circuit file not available")
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 @pytest.mark.skipif(
     "bluepy" not in os.environ.get("PYTHONPATH"),
     reason="Test requires bluepy run")
@@ -311,13 +305,9 @@ def constrained_hill(K_half):
     npt.assert_allclose(scale_factors(a, b), _constrained_hill(a, b))
 
 
-@pytest.mark.skipif(
-    not os.environ.get("NEURODAMUS_NEOCORTEX_ROOT"),
-    reason="Test requires loading a neocortex model to run")
 def test_no_edge_creation(capsys):
     from neurodamus.node import Node
 
-    USECASE3 = Path(__file__).parent.absolute() / "simulations" / "usecase3"
     contents = """
     {
         "manifest": {
diff --git a/tests/unit/README.md b/tests/unit/README.md
new file mode 100644
index 00000000..84650a49
--- /dev/null
+++ b/tests/unit/README.md
@@ -0,0 +1,10 @@
+## Neurodamus Unit Tests
+
+This folder contains the unit tests for Neurodamus.
+
+By definition a unit test shoult test a small functionality in isolation, which might require
+the use of mocks or even monkey-patching.
+
+In particular tests here should not rely on processing done by dependencies, especially NEURON,
+since it will not be fully configured. Those tests should instead be in the 'integration' test
+folder. Nevertheless, to ease life a bit, essential libraries like numpy and scipy can be relied on.
diff --git a/tests/unit/conftest.py b/tests/unit/conftest.py
new file mode 100644
index 00000000..1354ff4b
--- /dev/null
+++ b/tests/unit/conftest.py
@@ -0,0 +1,30 @@
+import pytest
+import sys
+import unittest
+
+
+class MockParallelExec:
+    """We need to create a replacement since a magic-mock will return garbage"""
+
+    def allreduce(self, number, _op):
+        return number
+
+
+@pytest.fixture(autouse=True, scope="module")
+def _mock_neuron():
+    from neurodamus.core import _mpi
+    from neurodamus.utils import compat
+    _mpi._MPI._pc = MockParallelExec()
+
+    # Dont convert
+    compat.hoc_vector = lambda x: x
+
+    class VectorMock(compat.Vector):
+
+        def __new__(cls, len=0):
+            init = [0] * len
+            return compat.Vector.__new__(cls, "d", init)
+
+    neuron_mock = unittest.mock.Mock()
+    neuron_mock.h.Vector = VectorMock
+    sys.modules['neuron'] = neuron_mock
diff --git a/tests/test_blueconfig_parser.py b/tests/unit/test_blueconfig_parser.py
similarity index 94%
rename from tests/test_blueconfig_parser.py
rename to tests/unit/test_blueconfig_parser.py
index 8a751121..d1ba568a 100644
--- a/tests/test_blueconfig_parser.py
+++ b/tests/unit/test_blueconfig_parser.py
@@ -3,7 +3,7 @@
 from pathlib import Path
 from contextlib import contextmanager
 
-BLUECONFIG_FILE = Path(__file__).parent.absolute() / "simulations" / "complex.blueconfig"
+BLUECONFIG_FILE = Path(__file__).parent.parent.absolute() / "simulations" / "complex.blueconfig"
 
 
 def test_blueconfig_parser():
diff --git a/tests/test_conn_manager.py b/tests/unit/test_conn_manager.py
similarity index 94%
rename from tests/test_conn_manager.py
rename to tests/unit/test_conn_manager.py
index 5a585402..2abe4265 100644
--- a/tests/test_conn_manager.py
+++ b/tests/unit/test_conn_manager.py
@@ -1,12 +1,8 @@
 import pytest
-from pathlib import Path
 from unittest import mock
 
 from neurodamus.connection_manager import ConnectionSet
 
-SIM_DIR = Path(__file__).parent.absolute() / "simulations"
-CIRCUIT_PATH = "/gpfs/bbp.cscs.ch/project/proj12/jenkins/cellular/circuit-2k"
-
 
 class _FakeConn:
     def __init__(self, sgid, tgid):
@@ -76,7 +72,7 @@ def test_population_all_conns():
         assert expected[i] == (conn.sgid, conn.tgid)
 
 
-@pytest.mark.parametrize("test_input, expected", [
+@pytest.mark.parametrize(("test_input", "expected"), [
     ((1,), [(0, 1), (1, 1)]),
     (([1],), [(0, 1), (1, 1)]),
     (([1, 2],), [(0, 1), (1, 1), (1, 2)]),
@@ -105,7 +101,7 @@ def test_population_delete():
         assert expected[i] == (conn.sgid, conn.tgid)
 
 
-@pytest.mark.parametrize("test_input, expected", [
+@pytest.mark.parametrize(("test_input", "expected"), [
     ((1,), [(0, 0), (1, 0), (1, 2)]),
     (([1],), [(0, 0), (1, 0), (1, 2)]),
     (([1, 2],), [(0, 0), (1, 0)]),
diff --git a/tests/test_coords.py b/tests/unit/test_coords.py
similarity index 100%
rename from tests/test_coords.py
rename to tests/unit/test_coords.py
diff --git a/tests/test_core_config.py b/tests/unit/test_core_config.py
similarity index 100%
rename from tests/test_core_config.py
rename to tests/unit/test_core_config.py
diff --git a/tests/test_dry_run.py b/tests/unit/test_dry_run.py
similarity index 100%
rename from tests/test_dry_run.py
rename to tests/unit/test_dry_run.py
diff --git a/tests/test_nodeset.py b/tests/unit/test_nodeset.py
similarity index 96%
rename from tests/test_nodeset.py
rename to tests/unit/test_nodeset.py
index 6719ef86..473a6cda 100644
--- a/tests/test_nodeset.py
+++ b/tests/unit/test_nodeset.py
@@ -44,7 +44,7 @@ def test_NodeSet_add():
     assert set_right.offset == 4000
 
 
-@pytest.mark.parametrize("ranges1, ranges2, expected", [
+@pytest.mark.parametrize(("ranges1", "ranges2", "expected"), [
     ([(0, 10), (20, 30)], [(8, 23), (28, 35)], numpy.array([8, 9, 20, 21, 22, 28, 29])),
     ([(0, 10), (20, 30)], [(10, 20)], []),
     ([(5, 10), (20, 30)], [(0, 10)], numpy.arange(5, 10)),
@@ -58,7 +58,7 @@ def test_ranges_overlap(ranges1, ranges2, expected):
     numpy.testing.assert_array_equal(out, expected)
 
 
-@pytest.mark.parametrize("ranges1, vec, expected", [
+@pytest.mark.parametrize(("ranges1", "vec", "expected"), [
     ([(0, 10), (20, 30)], [1, 2, 11, 12, 19, 20, 21, 29, 30], [1, 2, 20, 21, 29]),
     ([(0, 10), (20, 30)], [11, 12], []),
     ([], [], []),
diff --git a/tests/test_nodeset_target.py b/tests/unit/test_nodeset_target.py
similarity index 86%
rename from tests/test_nodeset_target.py
rename to tests/unit/test_nodeset_target.py
index 7ccbff9e..5f1274dc 100644
--- a/tests/test_nodeset_target.py
+++ b/tests/unit/test_nodeset_target.py
@@ -1,9 +1,13 @@
 import numpy
+import pytest
 
 
+@pytest.mark.forked
 def test_get_local_gids():
-    from neurodamus.core.nodeset import NodeSet
+
+    from neurodamus.core.nodeset import NodeSet, PopulationNodes
     from neurodamus.target_manager import NodesetTarget
+    PopulationNodes.reset()
     nodes_popA = NodeSet([1, 2]).register_global("pop_A")
     nodes_popB = NodeSet([1, 2]).register_global("pop_B")
     local_gids = [NodeSet([1]).register_global("pop_A"), NodeSet([2]).register_global("pop_B")]
diff --git a/tests/test_pyutils.py b/tests/unit/test_pyutils.py
similarity index 100%
rename from tests/test_pyutils.py
rename to tests/unit/test_pyutils.py
diff --git a/tests/test_replay_manager.py b/tests/unit/test_replay_manager.py
similarity index 90%
rename from tests/test_replay_manager.py
rename to tests/unit/test_replay_manager.py
index e9a69c0e..5ff96d80 100644
--- a/tests/test_replay_manager.py
+++ b/tests/unit/test_replay_manager.py
@@ -2,7 +2,7 @@
 import numpy.testing as npt
 from pathlib import Path
 
-SAMPLE_DATA_DIR = Path(__file__).parent.absolute() / "sample_data"
+SAMPLE_DATA_DIR = Path(__file__).parent.parent.absolute() / "sample_data"
 
 
 @pytest.mark.forked
diff --git a/tests/unit/test_stimuli.py b/tests/unit/test_stimuli.py
new file mode 100644
index 00000000..39c81886
--- /dev/null
+++ b/tests/unit/test_stimuli.py
@@ -0,0 +1,55 @@
+#!/usr/bin/env python
+"""
+Test suite for the new-gen Stimuli source (replacing TStim.hoc and parts of StimManager)
+"""
+import pytest
+from neurodamus.core import CurrentSource
+from neurodamus.core.random import Random123
+
+
+class TestStimuli:
+    def setup_method(self):
+        rng = Random123(1, 2, 3)
+        self.stim = CurrentSource(rng=rng)
+
+    def test_flat_segment(self):
+        self.stim.add_segment(1.2, 10)
+        assert list(self.stim.time_vec) == [0, 10]
+        assert list(self.stim.stim_vec) == [1.2, 1.2]
+
+    def test_pulse(self):
+        self.stim.add_pulse(1.2, 10)
+        assert list(self.stim.time_vec) == [0, 0, 10, 10]
+        assert list(self.stim.stim_vec) == [0, 1.2, 1.2, 0]
+
+    @pytest.mark.parametrize("base_amp", [-1, 0, 1.5])
+    def test_pulse_diff_base(self, base_amp):
+        self.stim.add_pulse(1.2, 10, base_amp=base_amp)
+        assert list(self.stim.time_vec) == [0, 0, 10, 10]
+        assert list(self.stim.stim_vec) == [base_amp, 1.2, 1.2, base_amp]
+
+    def test_two_pulses(self):
+        self.stim.add_pulse(1.2, 10)
+        self.stim.delay(5)
+        self.stim.add_pulse(0.8, 5)
+        assert list(self.stim.time_vec) == [0, 0, 10, 10, 15, 15, 20, 20]
+        assert list(self.stim.stim_vec) == [0, 1.2, 1.2, 0, 0, 0.8, 0.8, 0]
+
+    def test_ramp(self):
+        self.stim.add_ramp(5, 7.5, 10)
+        assert list(self.stim.time_vec) == [0, 0, 10, 10]
+        assert list(self.stim.stim_vec) == [0, 5, 7.5, 0]
+
+    def test_delay_ramp(self):
+        # When a delay is specified (in ctor or factory) base_amp is set on t=0 too
+        sig = CurrentSource.ramp(1, 2, 2, base_amp=-1, delay=10)
+        assert list(sig.time_vec) == [0, 10, 10, 12, 12]
+        assert list(sig.stim_vec) == [-1, -1, 1, 2, -1]
+
+    def test_train(self):
+        self.stim.add_train(1.2, 10, 20, 350)
+        # At 10Hz pulses have T=100ms
+        # We end up with 4 pulses, the last one with reduced rest phase
+        assert list(self.stim.time_vec) == [0, 0, 20, 20, 100, 100, 120, 120, 200, 200, 220, 220,
+                                            300, 300, 320, 320, 350]
+        assert list(self.stim.stim_vec) == [0, 1.2, 1.2, 0] * 4 + [0]
diff --git a/tests/test_target_intersection.py b/tests/unit/test_target_intersection.py
similarity index 94%
rename from tests/test_target_intersection.py
rename to tests/unit/test_target_intersection.py
index bd6e6b58..dc9b9687 100644
--- a/tests/test_target_intersection.py
+++ b/tests/unit/test_target_intersection.py
@@ -93,7 +93,7 @@ def test_nodeset_gids():
         local_nodes=[local_nodes_popA, local_nodes_popB]
     )
     gids = t.gids()
-    npt.assert_array_equal(gids.as_numpy(), [5, 6, 1003, 1004, 1005])
+    npt.assert_array_equal(gids, [5, 6, 1003, 1004, 1005])
 
     t2 = NodesetTarget(
         "target-b",
@@ -101,7 +101,7 @@ def test_nodeset_gids():
         local_nodes=[local_nodes_popA]
     )
     gids = t2.gids()
-    npt.assert_array_equal(gids.as_numpy(), [5, 6])
+    npt.assert_array_equal(gids, [5, 6])
 
     t3 = NodesetTarget(
         "target-c",
@@ -109,7 +109,7 @@ def test_nodeset_gids():
         local_nodes=[local_nodes_popA, local_nodes_popB]
     )
     gids = t3.gids()
-    npt.assert_array_equal(gids.as_numpy(), [1003, 1004, 1005])
+    npt.assert_array_equal(gids, [1003, 1004, 1005])
 
     t4 = NodesetTarget(
         "target-d",
@@ -117,4 +117,4 @@ def test_nodeset_gids():
         local_nodes=[local_nodes_popA]
     )
     gids = t4.gids()
-    npt.assert_array_equal(gids.as_numpy(), [])
+    npt.assert_array_equal(gids, [])
diff --git a/tox.ini b/tox.ini
index 5306ebb6..5626a33d 100644
--- a/tox.ini
+++ b/tox.ini
@@ -2,16 +2,21 @@
 name = neurodamus
 
 [tox]
-envlist = flake8, py3
+envlist = flake8, unit
 
 
-[testenv]
+[testenv:unit]
+deps =
+    -r tests/requirements.txt
+commands =
+    pytest tests/unit
+
+
+[testenv:integration]
 deps =
     NEURON
-    pytest
-    pytest-forked
-    scipy
     morphio
+    -r tests/requirements.txt
 passenv = NEURODAMUS_NEOCORTEX_ROOT
 setenv =
     # build_ndcore.sh will install into _lib
@@ -23,17 +28,14 @@ allowlist_externals =
     {toxinidir}/ci/build_ndcore.sh
 commands =
     {toxinidir}/ci/build_ndcore.sh {toxinidir}/core
-    python setup.py test
+    pytest -x --forked tests/integration
 
 
-[testenv:bb5]
+[testenv:bbp-model]
 # Please module load neurodamus-neocortex py-neurodamus beforehand
 passenv = *
 deps =
-    pytest
-    pytest-cov
-    pytest-forked
-    pytest-xdist
+    -r tests/requirements.txt
 setenv =
     PYTHONPATH={toxinidir}:{env:PYTHONPATH}
     HOC_LIBRARY_PATH={toxinidir}/core/hoc:{env:HOC_LIBRARY_PATH}
@@ -43,7 +45,7 @@ allowlist_externals =
 commands =
     /usr/bin/echo {env:PYTHONPATH}
     /usr/bin/echo {env:HOC_LIBRARY_PATH}
-    pytest -s -x -n2 --forked --cov=neurodamus
+    pytest -s -x --forked --durations=5 --durations-min=15 {posargs:tests/integration-e2e}
 
 
 [testenv:flake8]