diff --git a/conda/meta.yaml b/conda/meta.yaml
index d7d37749..1c071010 100644
--- a/conda/meta.yaml
+++ b/conda/meta.yaml
@@ -18,23 +18,24 @@ requirements:
     - python
     - setuptools
   run:
+    - bottleneck
+    - bw2data
+    - bw2io >=0.8.10
+    - constructive_geometries>=0.8.2
+    - cryptography
+    - datapackage
     - numpy
     - pandas
-    - bw2io >=0.8.10
-    - bw2data
-    - wurst
-    - xarray
+    - platformdirs
     - prettytable
+    - pyarrow
     - pycountry
-    - cryptography
     - pyYaml
-    - sparse>=0.14.0
-    - schema
-    - datapackage
     - requests
-    - bottleneck
-    - constructive_geometries>=0.8.2
-    - pyarrow
+    - schema
+    - sparse>=0.14.0
+    - wurst
+    - xarray
 
 test:
   imports:
diff --git a/premise/__init__.py b/premise/__init__.py
index 2f0ae4ed..af001f36 100644
--- a/premise/__init__.py
+++ b/premise/__init__.py
@@ -1,11 +1,6 @@
 __all__ = ("NewDatabase", "clear_cache", "get_regions_definition")
 __version__ = (1, 7, 6)
 
-from pathlib import Path
-
-DATA_DIR = Path(__file__).resolve().parent / "data"
-INVENTORY_DIR = Path(__file__).resolve().parent / "data" / "additional_inventories"
-VARIABLES_DIR = Path(__file__).resolve().parent / "iam_variables_mapping"
 
 from .ecoinvent_modification import NewDatabase
 from .utils import clear_cache, get_regions_definition
diff --git a/premise/activity_maps.py b/premise/activity_maps.py
index 7ae8bef9..5f6b8f86 100644
--- a/premise/activity_maps.py
+++ b/premise/activity_maps.py
@@ -3,7 +3,6 @@
 mapping between ``premise`` and ``ecoinvent`` terminology.
 """
 
-import sys
 from collections import defaultdict
 from pathlib import Path
 from typing import List, Union
@@ -11,7 +10,7 @@
 import yaml
 from wurst import searching as ws
 
-from . import DATA_DIR, VARIABLES_DIR
+from .filesystem_constants import DATA_DIR, VARIABLES_DIR
 
 POWERPLANT_TECHS = VARIABLES_DIR / "electricity_variables.yaml"
 FUELS_TECHS = VARIABLES_DIR / "fuels_variables.yaml"
diff --git a/premise/cement.py b/premise/cement.py
index 47e38a7d..e044d183 100644
--- a/premise/cement.py
+++ b/premise/cement.py
@@ -8,15 +8,10 @@
 
 """
 
-import logging.config
 from collections import defaultdict
-from pathlib import Path
-
-import yaml
 
 from .logger import create_logger
 from .transformation import BaseTransformation, Dict, IAMDataCollection, List, np, ws
-from .utils import DATA_DIR
 
 logger = create_logger("cement")
 
diff --git a/premise/clean_datasets.py b/premise/clean_datasets.py
index 5f49fdfc..af965c90 100644
--- a/premise/clean_datasets.py
+++ b/premise/clean_datasets.py
@@ -14,8 +14,8 @@
 from bw2data.database import DatabaseChooser
 from wurst import searching as ws
 
-from . import DATA_DIR
 from .data_collection import get_delimiter
+from .filesystem_constants import DATA_DIR
 
 
 def remove_uncertainty(database):
diff --git a/premise/data_collection.py b/premise/data_collection.py
index 43a362b5..e31ea460 100644
--- a/premise/data_collection.py
+++ b/premise/data_collection.py
@@ -19,7 +19,7 @@
 import yaml
 from cryptography.fernet import Fernet
 
-from . import DATA_DIR, VARIABLES_DIR
+from .filesystem_constants import DATA_DIR, IAM_OUTPUT_DIR, VARIABLES_DIR
 from .marginal_mixes import consequential_method
 
 IAM_ELEC_VARS = VARIABLES_DIR / "electricity_variables.yaml"
@@ -30,11 +30,9 @@
 IAM_STEEL_VARS = VARIABLES_DIR / "steel_variables.yaml"
 IAM_DAC_VARS = VARIABLES_DIR / "direct_air_capture_variables.yaml"
 IAM_OTHER_VARS = VARIABLES_DIR / "other_variables.yaml"
-FILEPATH_FLEET_COMP = (
-    DATA_DIR / "iam_output_files" / "fleet_files" / "fleet_all_vehicles.csv"
-)
+FILEPATH_FLEET_COMP = IAM_OUTPUT_DIR / "fleet_files" / "fleet_all_vehicles.csv"
 FILEPATH_IMAGE_TRUCKS_FLEET_COMP = (
-    DATA_DIR / "iam_output_files" / "fleet_files" / "image_fleet_trucks.csv"
+    IAM_OUTPUT_DIR / "fleet_files" / "image_fleet_trucks.csv"
 )
 VEHICLES_MAP = DATA_DIR / "transport" / "vehicles_map.yaml"
 IAM_CARBON_CAPTURE_VARS = VARIABLES_DIR / "carbon_capture_variables.yaml"
diff --git a/premise/direct_air_capture.py b/premise/direct_air_capture.py
index c715f60f..ad881e32 100644
--- a/premise/direct_air_capture.py
+++ b/premise/direct_air_capture.py
@@ -3,20 +3,13 @@
 """
 
 import copy
-import logging.config
-from pathlib import Path
 
+import numpy as np
 import wurst
 import yaml
 
+from .filesystem_constants import DATA_DIR
 from .logger import create_logger
-from .utils import DATA_DIR
-
-logger = create_logger("dac")
-
-
-import numpy as np
-
 from .transformation import (
     BaseTransformation,
     IAMDataCollection,
@@ -26,6 +19,8 @@
     ws,
 )
 
+logger = create_logger("dac")
+
 HEAT_SOURCES = DATA_DIR / "fuels" / "heat_sources_map.yml"
 
 
diff --git a/premise/ecoinvent_modification.py b/premise/ecoinvent_modification.py
index 71be8813..90033eb2 100644
--- a/premise/ecoinvent_modification.py
+++ b/premise/ecoinvent_modification.py
@@ -18,7 +18,7 @@
 import datapackage
 import yaml
 
-from . import DATA_DIR, INVENTORY_DIR, __version__
+from . import __version__
 from .cement import _update_cement
 from .clean_datasets import DatabaseCleaner
 from .data_collection import IAMDataCollection
@@ -34,6 +34,7 @@
 )
 from .external import ExternalScenario
 from .external_data_validation import check_external_scenarios, check_inventories
+from .filesystem_constants import DATA_DIR, DIR_CACHED_DB, IAM_OUTPUT_DIR, INVENTORY_DIR
 from .fuels import _update_fuels
 from .inventory_imports import AdditionalInventory, DefaultInventory
 from .report import generate_change_report, generate_summary_report
@@ -51,8 +52,6 @@
     write_brightway2_database,
 )
 
-DIR_CACHED_DB = DATA_DIR / "cache"
-
 FILEPATH_OIL_GAS_INVENTORIES = INVENTORY_DIR / "lci-ESU-oil-and-gas.xlsx"
 FILEPATH_CARMA_INVENTORIES = INVENTORY_DIR / "lci-Carma-CCS.xlsx"
 FILEPATH_CO_FIRING_INVENTORIES = INVENTORY_DIR / "lci-co-firing-power-plants.xlsx"
@@ -344,7 +343,8 @@ def check_scenarios(scenario: dict, key: bytes) -> dict:
         filepath = scenario["filepath"]
         scenario["filepath"] = check_filepath(filepath)
     else:
-        scenario["filepath"] = DATA_DIR / "iam_output_files"
+        # Note: A directory path, not a file path
+        scenario["filepath"] = IAM_OUTPUT_DIR
         if key is None:
             raise ValueError(
                 "You need to provide the encryption key to decrypt the IAM output files provided by `premise`."
@@ -633,13 +633,11 @@ def __find_cached_db(self, db_name: str, keep_uncertainty_data: bool) -> List[di
         :param db_name: database name
         :return: database
         """
-        # check that directory exists, otherwise create it
-        Path(DIR_CACHED_DB).mkdir(parents=True, exist_ok=True)
         # build file path
         if db_name is None and self.source_type == "ecospold":
             db_name = f"ecospold_{self.system_model}_{self.version}"
 
-        file_name = Path(
+        file_name = (
             DIR_CACHED_DB
             / f"cached_{''.join(tuple(map( str , __version__ )))}_{db_name.strip().lower()}.pickle"
         )
@@ -663,13 +661,11 @@ def __find_cached_inventories(self, db_name: str) -> Union[None, List[dict]]:
         :param db_name: database name
         :return: database
         """
-        # check that directory exists, otherwise create it
-        Path(DIR_CACHED_DB).mkdir(parents=True, exist_ok=True)
         # build file path
         if db_name is None and self.source_type == "ecospold":
             db_name = f"ecospold_{self.system_model}_{self.version}"
 
-        file_name = Path(
+        file_name = (
             DIR_CACHED_DB
             / f"cached_{''.join(tuple(map( str , __version__ )))}_{db_name.strip().lower()}_inventories.pickle"
         )
@@ -1602,7 +1598,7 @@ def write_datapackage(self, name: str = f"datapackage_{date.today()}"):
         cached_inventories = self.__find_cached_inventories(self.source)
 
         if not cached_inventories:
-            cache_fp = DATA_DIR / "cache" / f"cached_{self.source}_inventories.pickle"
+            cache_fp = DIR_CACHED_DB / f"cached_{self.source}_inventories.pickle"
             raise ValueError(f"No cached inventories found at {cache_fp}.")
 
         cache = {}
diff --git a/premise/electricity.py b/premise/electricity.py
index b5193aff..31998848 100644
--- a/premise/electricity.py
+++ b/premise/electricity.py
@@ -13,14 +13,13 @@
 import re
 from collections import defaultdict
 from functools import lru_cache
-from pprint import pprint
 
 import wurst
 import yaml
 
-from . import VARIABLES_DIR
 from .data_collection import get_delimiter
 from .export import biosphere_flows_dictionary
+from .filesystem_constants import DATA_DIR, VARIABLES_DIR
 from .logger import create_logger
 from .transformation import (
     BaseTransformation,
@@ -35,7 +34,7 @@
     uuid,
     ws,
 )
-from .utils import DATA_DIR, eidb_label, get_efficiency_solar_photovoltaics
+from .utils import eidb_label, get_efficiency_solar_photovoltaics
 
 LOSS_PER_COUNTRY = DATA_DIR / "electricity" / "losses_per_country.csv"
 IAM_BIOMASS_VARS = VARIABLES_DIR / "biomass_variables.yaml"
diff --git a/premise/emissions.py b/premise/emissions.py
index 9d022760..272fed7e 100644
--- a/premise/emissions.py
+++ b/premise/emissions.py
@@ -3,9 +3,7 @@
 from GAINS.
 """
 
-import logging.config
 from functools import lru_cache
-from pathlib import Path
 from typing import Union
 
 import numpy as np
@@ -14,6 +12,7 @@
 import yaml
 from numpy import ndarray
 
+from .filesystem_constants import DATA_DIR
 from .logger import create_logger
 from .transformation import (
     BaseTransformation,
@@ -24,7 +23,6 @@
     Set,
     ws,
 )
-from .utils import DATA_DIR
 
 logger = create_logger("emissions")
 
diff --git a/premise/export.py b/premise/export.py
index 305bba43..18419e9d 100644
--- a/premise/export.py
+++ b/premise/export.py
@@ -11,10 +11,9 @@
 import uuid
 from collections import defaultdict
 from functools import lru_cache
-from multiprocessing import Pool as ProcessPool
 from multiprocessing.pool import ThreadPool as Pool
 from pathlib import Path
-from typing import Any, Dict, List, Set, Tuple, Union
+from typing import Any, Dict, List
 
 import numpy as np
 import pandas as pd
@@ -24,8 +23,9 @@
 from pandas import DataFrame
 from scipy import sparse as nsp
 
-from . import DATA_DIR, __version__
+from . import __version__
 from .data_collection import get_delimiter
+from .filesystem_constants import DATA_DIR
 from .inventory_imports import get_correspondence_bio_flows
 from .transformation import BaseTransformation
 from .utils import check_database_name
diff --git a/premise/external.py b/premise/external.py
index 7db91b58..e26c5f28 100644
--- a/premise/external.py
+++ b/premise/external.py
@@ -1,14 +1,23 @@
 """
 Implements external scenario data.
 """
+import logging
+import uuid
+from collections import defaultdict
+from pathlib import Path
+from typing import List, Union
 
-
+import numpy as np
 import wurst
-from numpy import ndarray
+import xarray as xr
+import yaml
+from wurst import searching as ws
 
 from .clean_datasets import get_biosphere_flow_uuid
+from .data_collection import IAMDataCollection
+from .filesystem_constants import DATA_DIR
 from .inventory_imports import generate_migration_maps, get_correspondence_bio_flows
-from .transformation import *
+from .transformation import BaseTransformation, get_shares_from_production_volume
 from .utils import eidb_label
 
 LOG_CONFIG = DATA_DIR / "utils" / "logging" / "logconfig.yaml"
@@ -679,14 +688,14 @@ def check_existence_of_market_suppliers(self):
 
     def fetch_supply_share(
         self, i: int, region: str, var: str, variables: list
-    ) -> ndarray:
+    ) -> np.ndarray:
         """
         Return the supply share of a given variable in a given region.
         :param i: index of the scenario
         :param region: region
         :param var: variable
         :param variables: list of all variables
-        :return: ndarray
+        :return: np.ndarray
         """
 
         return np.clip(
@@ -858,7 +867,7 @@ def adjust_efficiency_of_new_markets(
                 ineff["variable"], region, eff_data, self.year
             )
 
-            if not "includes" in ineff:
+            if "includes" not in ineff:
                 wurst.change_exchanges_by_constant_factor(datatset, scaling_factor)
 
             else:
diff --git a/premise/external_data_validation.py b/premise/external_data_validation.py
index e4a117ea..0490877a 100644
--- a/premise/external_data_validation.py
+++ b/premise/external_data_validation.py
@@ -1,10 +1,6 @@
 """
 Validates datapackages that contain external scenario data.
 """
-
-import sys
-from pprint import pprint
-
 import numpy as np
 import pandas as pd
 import yaml
diff --git a/premise/filesystem_constants.py b/premise/filesystem_constants.py
new file mode 100644
index 00000000..16e7fc4b
--- /dev/null
+++ b/premise/filesystem_constants.py
@@ -0,0 +1,20 @@
+from pathlib import Path
+
+import platformdirs
+
+# Directories for data which comes with Premise
+DATA_DIR = Path(__file__).resolve().parent / "data"
+INVENTORY_DIR = DATA_DIR / "additional_inventories"
+# Todo: Should this be in the data directory?
+VARIABLES_DIR = Path(__file__).resolve().parent / "iam_variables_mapping"
+IAM_OUTPUT_DIR = DATA_DIR / "iam_output_files"
+
+# Directories for user-created data
+USER_DATA_BASE_DIR = platformdirs.user_data_path(appname="premise", appauthor="pylca")
+USER_DATA_BASE_DIR.mkdir(parents=True, exist_ok=True)
+
+DIR_CACHED_DB = USER_DATA_BASE_DIR / "cache"
+DIR_CACHED_DB.mkdir(parents=True, exist_ok=True)
+
+USER_LOGS_DIR = platformdirs.user_log_path(appname="premise", appauthor="pylca")
+USER_LOGS_DIR.mkdir(parents=True, exist_ok=True)
diff --git a/premise/fuels.py b/premise/fuels.py
index 225681aa..6fb852f8 100644
--- a/premise/fuels.py
+++ b/premise/fuels.py
@@ -3,9 +3,7 @@
 """
 
 import copy
-import logging.config
 from functools import lru_cache
-from pathlib import Path
 from typing import Union
 
 import wurst
@@ -13,7 +11,7 @@
 import yaml
 from numpy import ndarray
 
-from . import VARIABLES_DIR
+from .filesystem_constants import DATA_DIR, VARIABLES_DIR
 from .inventory_imports import get_biosphere_code
 from .logger import create_logger
 from .transformation import (
@@ -30,7 +28,7 @@
     uuid,
     ws,
 )
-from .utils import DATA_DIR, get_crops_properties
+from .utils import get_crops_properties
 
 logger = create_logger("fuel")
 
diff --git a/premise/geomap.py b/premise/geomap.py
index bcaf89ab..dcb1ea67 100644
--- a/premise/geomap.py
+++ b/premise/geomap.py
@@ -9,7 +9,7 @@
 import yaml
 from wurst import geomatcher
 
-from . import DATA_DIR, VARIABLES_DIR
+from .filesystem_constants import VARIABLES_DIR
 
 ECO_IAM_MAPPING = VARIABLES_DIR / "missing_geography_equivalences.yaml"
 
diff --git a/premise/inventory_imports.py b/premise/inventory_imports.py
index 0049cd19..af62de45 100644
--- a/premise/inventory_imports.py
+++ b/premise/inventory_imports.py
@@ -5,7 +5,6 @@
 
 import csv
 import itertools
-import sys
 import uuid
 from functools import lru_cache
 from pathlib import Path
@@ -19,9 +18,9 @@
 from prettytable import PrettyTable
 from wurst import searching as ws
 
-from . import DATA_DIR, INVENTORY_DIR
 from .clean_datasets import remove_categories, remove_uncertainty
 from .data_collection import get_delimiter
+from .filesystem_constants import DATA_DIR, DIR_CACHED_DB, INVENTORY_DIR
 from .geomap import Geomap
 
 FILEPATH_MIGRATION_MAP = INVENTORY_DIR / "migration_map.csv"
@@ -822,8 +821,7 @@ def load_inventory(self, path):
             # online file
             # we need to save it locally first
             response = requests.get(path)
-            Path(DATA_DIR / "cache").mkdir(parents=True, exist_ok=True)
-            path = str(Path(DATA_DIR / "cache" / "temp.csv"))
+            path = DIR_CACHED_DB / "temp.csv"
             with open(path, "w", encoding="utf-8") as f:
                 writer = csv.writer(
                     f,
@@ -835,9 +833,9 @@ def load_inventory(self, path):
                 for line in response.iter_lines():
                     writer.writerow(line.decode("utf-8").split(","))
 
-        if Path(path).suffix == ".xlsx":
+        if path.suffix == ".xlsx":
             return ExcelImporter(path)
-        elif Path(path).suffix == ".csv":
+        elif path.suffix == ".csv":
             return CSVImporter(path)
         else:
             raise ValueError(
diff --git a/premise/logger.py b/premise/logger.py
index f2aa3beb..903df805 100644
--- a/premise/logger.py
+++ b/premise/logger.py
@@ -1,10 +1,9 @@
 import logging.config
-import multiprocessing
 from pathlib import Path
 
 import yaml
 
-from . import DATA_DIR
+from .filesystem_constants import DATA_DIR
 
 LOG_CONFIG = DATA_DIR / "utils" / "logging" / "logconfig.yaml"
 DIR_LOG_REPORT = Path.cwd() / "export" / "logs"
diff --git a/premise/marginal_mixes.py b/premise/marginal_mixes.py
index af952769..b03c49c8 100644
--- a/premise/marginal_mixes.py
+++ b/premise/marginal_mixes.py
@@ -13,7 +13,7 @@
 import yaml
 from numpy import ndarray
 
-from premise import DATA_DIR
+from .filesystem_constants import DATA_DIR
 
 IAM_LEADTIMES = DATA_DIR / "consequential" / "leadtimes.yaml"
 IAM_LIFETIMES = DATA_DIR / "consequential" / "lifetimes.yaml"
diff --git a/premise/report.py b/premise/report.py
index dced5b6b..46cb496b 100644
--- a/premise/report.py
+++ b/premise/report.py
@@ -15,10 +15,10 @@
 from openpyxl.utils import get_column_letter
 from openpyxl.utils.dataframe import dataframe_to_rows
 from openpyxl.worksheet.dimensions import ColumnDimension, DimensionHolder
-from pandas._libs.parsers import ParserError
 from pandas.errors import EmptyDataError
 
-from . import DATA_DIR, VARIABLES_DIR, __version__
+from . import __version__
+from .filesystem_constants import DATA_DIR, VARIABLES_DIR
 
 IAM_ELEC_VARS = VARIABLES_DIR / "electricity_variables.yaml"
 IAM_FUELS_VARS = VARIABLES_DIR / "fuels_variables.yaml"
diff --git a/premise/steel.py b/premise/steel.py
index f9e31554..28858e01 100644
--- a/premise/steel.py
+++ b/premise/steel.py
@@ -1,17 +1,13 @@
 """
 Integrates projections regarding steel production.
 """
-import logging.config
-from pathlib import Path
 from typing import Dict, List
 
 import wurst
-import yaml
 
 from .data_collection import IAMDataCollection
 from .logger import create_logger
 from .transformation import BaseTransformation, ws
-from .utils import DATA_DIR
 
 logger = create_logger("steel")
 
diff --git a/premise/transformation.py b/premise/transformation.py
index 71dfa501..36b9ef88 100644
--- a/premise/transformation.py
+++ b/premise/transformation.py
@@ -25,8 +25,9 @@
 
 from .activity_maps import InventorySet
 from .data_collection import IAMDataCollection
+from .filesystem_constants import DATA_DIR
 from .geomap import Geomap
-from .utils import DATA_DIR, get_fuel_properties
+from .utils import get_fuel_properties
 
 LOG_CONFIG = DATA_DIR / "utils" / "logging" / "logconfig.yaml"
 # directory for log files
diff --git a/premise/transport.py b/premise/transport.py
index 60f093da..3430679b 100644
--- a/premise/transport.py
+++ b/premise/transport.py
@@ -14,16 +14,14 @@
 from wurst import searching as ws
 from wurst import transformations as wt
 
-from . import DATA_DIR, INVENTORY_DIR
+from .filesystem_constants import DATA_DIR, IAM_OUTPUT_DIR, INVENTORY_DIR
 from .inventory_imports import VariousVehicles
 from .transformation import BaseTransformation, IAMDataCollection
 from .utils import eidb_label
 
-FILEPATH_FLEET_COMP = (
-    DATA_DIR / "iam_output_files" / "fleet_files" / "fleet_all_vehicles.csv"
-)
+FILEPATH_FLEET_COMP = IAM_OUTPUT_DIR / "fleet_files" / "fleet_all_vehicles.csv"
 FILEPATH_IMAGE_TRUCKS_FLEET_COMP = (
-    DATA_DIR / "iam_output_files" / "fleet_files" / "image_fleet_trucks.csv"
+    IAM_OUTPUT_DIR / "fleet_files" / "image_fleet_trucks.csv"
 )
 FILEPATH_TWO_WHEELERS = INVENTORY_DIR / "lci-two_wheelers.xlsx"
 FILEPATH_TRUCKS = INVENTORY_DIR / "lci-trucks.xlsx"
diff --git a/premise/utils.py b/premise/utils.py
index 48efd81e..d89105c4 100644
--- a/premise/utils.py
+++ b/premise/utils.py
@@ -7,7 +7,7 @@
 import uuid
 from functools import lru_cache
 from pathlib import Path
-from typing import List
+from typing import List, Optional
 
 import pandas as pd
 import xarray as xr
@@ -16,16 +16,12 @@
 from bw2io.importers.base_lci import LCIImporter
 from country_converter import CountryConverter
 from prettytable import ALL, PrettyTable
-from wurst.linking import (
-    change_db_name,
-    check_duplicate_codes,
-    check_internal_linking,
-    link_internal,
-)
+from wurst.linking import change_db_name, check_internal_linking, link_internal
 from wurst.searching import equals, get_many
 
-from . import DATA_DIR, VARIABLES_DIR, __version__
+from . import __version__
 from .data_collection import get_delimiter
+from .filesystem_constants import DATA_DIR, DIR_CACHED_DB, VARIABLES_DIR
 from .geomap import Geomap
 
 FUELS_PROPERTIES = VARIABLES_DIR / "fuels_variables.yaml"
@@ -160,7 +156,7 @@ def get_regions_definition(model: str) -> None:
     print(table)
 
 
-def clear_existing_cache():
+def clear_existing_cache(all_versions: Optional[bool] = False) -> None:
     """Clears the cache folder, except for files which contain __version__ in name.
     Useful when updating `premise`
     or encountering issues with
@@ -168,14 +164,15 @@ def clear_existing_cache():
     """
     [
         f.unlink()
-        for f in Path(DATA_DIR / "cache").glob("*")
-        if f.is_file() and "".join(tuple(map(str, __version__))) not in f.name
+        for f in DIR_CACHED_DB.glob("*")
+        if f.is_file()
+        and (all_versions or "".join(tuple(map(str, __version__))) not in f.name)
     ]
 
 
 # clear the cache folder
-def clear_cache():
-    [f.unlink() for f in Path(DATA_DIR / "cache").glob("*") if f.is_file()]
+def clear_cache() -> None:
+    clear_existing_cache(all_versions=True)
     print("Cache folder cleared!")
 
 
diff --git a/requirements.txt b/requirements.txt
index f57a1164..346c35a6 100644
--- a/requirements.txt
+++ b/requirements.txt
@@ -1,18 +1,19 @@
+bottleneck
+bw2data
+bw2io>=0.8.10
+constructive_geometries>=0.8.2
+cryptography
+datapackage
 numpy
 pandas
-bw2io>=0.8.10
-bw2data
-wurst
-xarray
+platformdirs
+premise_gwp
 prettytable
+pyarrow
 pycountry
-cryptography
-premise_gwp
 pyYaml
-sparse>=0.14.0
-schema
-datapackage
 requests
-bottleneck
-constructive_geometries>=0.8.2
-pyarrow
+schema
+sparse>=0.14.0
+wurst
+xarray
diff --git a/setup.py b/setup.py
index d777d93e..7cad73bf 100644
--- a/setup.py
+++ b/setup.py
@@ -41,25 +41,26 @@ def package_files(directory):
     # Only if you have non-python data (CSV, etc.). Might need to change the directory name as well.
     include_package_data=True,
     install_requires=[
-        "numpy",
-        "wurst",
+        "bottleneck",
+        "bw2data",
         # bw2io 0.8.7 or 0.8.10
         "bw2io >=0.8.10",
+        "constructive_geometries>=0.8.2",
+        "cryptography",
+        "datapackage",
+        "numpy",
         "pandas",
-        "bw2data",
-        "xarray",
+        "platformdirs",
+        "premise_gwp",
         "prettytable",
+        "pyarrow",
         "pycountry",
-        "cryptography",
-        "premise_gwp",
         "pyYaml",
-        "sparse>=0.14.0",
-        "schema",
-        "datapackage",
         "requests",
-        "bottleneck",
-        "constructive_geometries>=0.8.2",
-        "pyarrow",
+        "schema",
+        "sparse>=0.14.0",
+        "wurst",
+        "xarray",
     ],
     url="https://github.com/polca/premise",
     description="Coupling IAM output to ecoinvent LCA database ecoinvent for prospective LCA",
diff --git a/tests/test_electricity.py b/tests/test_electricity.py
index 08d0b6c3..5f941cb0 100644
--- a/tests/test_electricity.py
+++ b/tests/test_electricity.py
@@ -1,9 +1,12 @@
 # content of test_electricity.py
 import os
+from pathlib import Path
+
+import pytest
 
-from premise import DATA_DIR
 from premise.data_collection import IAMDataCollection
 from premise.electricity import Electricity
+from premise.filesystem_constants import DATA_DIR
 
 LOSS_PER_COUNTRY = DATA_DIR / "electricity" / "losses_per_country.csv"
 LHV_FUELS = DATA_DIR / "fuels_lower_heating_value.txt"
@@ -40,38 +43,48 @@ def get_db():
     return dummy_db, version
 
 
+# This won't work with PRs because PRs from outside contributors don't have
+# access to secrets (for good reason).
 if "IAM_FILES_KEY" in os.environ:
     key = os.environ["IAM_FILES_KEY"]
 else:
-    with open("/Users/romain/Dropbox/Notebooks/key.txt") as f:
-        lines = f.readlines()
-    key = lines[0]
+    # This won't work on most computers :)
+    if Path("/Users/romain/Dropbox/Notebooks/key.txt").is_file():
+        with open("/Users/romain/Dropbox/Notebooks/key.txt") as f:
+            lines = f.readlines()
+        key = lines[0]
+    else:
+        key = None
+
 
-rdc = IAMDataCollection(
-    model="remind",
-    pathway="SSP2-Base",
-    year=2012,
-    filepath_iam_files=DATA_DIR / "iam_output_files",
-    key=str.encode(key),
-)
-db, _ = get_db()
-el = Electricity(
-    database=db,
-    iam_data=rdc,
-    model="remind",
-    pathway="SSP2-Base",
-    year=2012,
-    version="3.5",
-    system_model="cutoff",
-    modified_datasets={},
-)
+if key:
+    rdc = IAMDataCollection(
+        model="remind",
+        pathway="SSP2-Base",
+        year=2012,
+        filepath_iam_files=DATA_DIR / "iam_output_files",
+        key=str.encode(key),
+    )
+    db, _ = get_db()
+    el = Electricity(
+        database=db,
+        iam_data=rdc,
+        model="remind",
+        pathway="SSP2-Base",
+        year=2012,
+        version="3.5",
+        system_model="cutoff",
+        modified_datasets={},
+    )
 
 
+@pytest.mark.skipif(not key, reason="No access to decryption key")
 def test_losses():
     assert len(el.network_loss) == 13
     assert el.network_loss["CAZ"]["high"]["transf_loss"] == 0.035483703331573094
 
 
+@pytest.mark.skipif(not key, reason="No access to decryption key")
 def test_powerplant_map():
     s = el.powerplant_map["Biomass IGCC CCS"]
     assert isinstance(s, set)
diff --git a/tests/test_filesystem_constants.py b/tests/test_filesystem_constants.py
new file mode 100644
index 00000000..73de56a6
--- /dev/null
+++ b/tests/test_filesystem_constants.py
@@ -0,0 +1,61 @@
+import os
+from pathlib import Path
+
+from premise.filesystem_constants import (
+    DATA_DIR,
+    DIR_CACHED_DB,
+    IAM_OUTPUT_DIR,
+    INVENTORY_DIR,
+    VARIABLES_DIR,
+)
+
+dd_root = str(DATA_DIR.parent.parent)
+cd_root = str(DIR_CACHED_DB.parent.parent)
+
+
+def test_data_dir():
+    assert isinstance(DATA_DIR, Path)
+    assert DATA_DIR.is_dir()
+    assert len(list(DATA_DIR.iterdir())) > 2
+    for fp in DATA_DIR.iterdir():
+        assert os.access(fp, os.R_OK)
+    assert dd_root not in cd_root and cd_root not in dd_root
+
+
+def test_inventory_dir():
+    assert isinstance(INVENTORY_DIR, Path)
+    assert INVENTORY_DIR.is_dir()
+    for fp in INVENTORY_DIR.iterdir():
+        assert os.access(fp, os.R_OK)
+    assert len(list(INVENTORY_DIR.iterdir())) > 2
+    assert str(DATA_DIR) in str(INVENTORY_DIR)
+
+
+def test_variables_dir():
+    assert isinstance(VARIABLES_DIR, Path)
+    assert VARIABLES_DIR.is_dir()
+    assert len(list(VARIABLES_DIR.iterdir())) > 2
+    for fp in VARIABLES_DIR.iterdir():
+        assert os.access(fp, os.R_OK)
+    assert str(DATA_DIR) not in str(VARIABLES_DIR)
+    assert dd_root in str(VARIABLES_DIR)
+    assert cd_root not in str(VARIABLES_DIR)
+
+
+def test_iam_output_dir():
+    assert isinstance(IAM_OUTPUT_DIR, Path)
+    assert IAM_OUTPUT_DIR.is_dir()
+    for fp in IAM_OUTPUT_DIR.iterdir():
+        assert os.access(fp, os.R_OK)
+    assert len(list(IAM_OUTPUT_DIR.iterdir())) > 2
+    assert str(DATA_DIR) in str(IAM_OUTPUT_DIR)
+
+
+def test_user_data_dir():
+    assert isinstance(DIR_CACHED_DB, Path)
+    assert DIR_CACHED_DB.is_dir()
+    assert os.access(DIR_CACHED_DB, os.W_OK)
+    assert os.access(DIR_CACHED_DB, os.R_OK)
+    assert cd_root in str(DIR_CACHED_DB)
+    assert dd_root not in str(DIR_CACHED_DB)
+    assert "cache" in str(DIR_CACHED_DB)
diff --git a/tests/test_import_inventories.py b/tests/test_import_inventories.py
index ff2749dc..f9378f9d 100644
--- a/tests/test_import_inventories.py
+++ b/tests/test_import_inventories.py
@@ -3,7 +3,7 @@
 
 import pytest
 
-from premise import INVENTORY_DIR
+from premise.filesystem_constants import INVENTORY_DIR
 from premise.inventory_imports import BaseInventoryImport, DefaultInventory
 
 FILEPATH_CARMA_INVENTORIES = INVENTORY_DIR / "lci-Carma-CCS.xlsx"