diff --git a/.circleci/config.yml b/.circleci/config.yml
index 986bf3cc33..00a2995b34 100644
--- a/.circleci/config.yml
+++ b/.circleci/config.yml
@@ -26,7 +26,7 @@ jobs:
       - run:
           name: Install dependencies
           command: |
-            make install-deps
+            make clean install-deps
             # pip install --editable git+https://github.com/openfisca/country-template.git@BRANCH_NAME#egg=OpenFisca-Country-Template  # use a specific branch of OpenFisca-Country-Template
             # pip install --editable git+https://github.com/openfisca/extension-template.git@BRANCH_NAME#egg=OpenFisca-Extension-Template  # use a specific branch of OpenFisca-Extension-Template
 
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 82ea091375..42ea9b44f3 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,5 +1,12 @@
 # Changelog
 
+### 35.5.4 [#1059](https://github.com/openfisca/openfisca-core/pull/1059)
+
+#### Non-technical changes
+
+- Move published code to `src`.
+- Use `setup.cfg` for metadata.
+
 ### 35.5.3 [#1058](https://github.com/openfisca/openfisca-core/pull/1058)
 
 #### Non-technical changes
diff --git a/MANIFEST.in b/MANIFEST.in
index 166788d7fa..dfdedebca3 100644
--- a/MANIFEST.in
+++ b/MANIFEST.in
@@ -1,2 +1,2 @@
-recursive-include openfisca_core/scripts *
-include openfisca_web_api/openAPI.yml
+recursive-include src *
+global-exclude *.py[cod]
diff --git a/setup.cfg b/setup.cfg
index 4f98591eeb..3e9bf9b0e4 100644
--- a/setup.cfg
+++ b/setup.cfg
@@ -1,10 +1,46 @@
-; E128/133: We prefer hang-closing visual indents
-; E251:     We prefer `function(x = 1)` over `function(x=1)`
-; E501:     We do not enforce a maximum line length
-; F403/405: We ignore * imports
-; W503/504: We break lines before binary operators (Knuth's style)
+[metadata]
+name = OpenFisca-Core
+version = 35.5.4
+author = OpenFisca Team
+author_email = contact@openfisca.org
+license = https://www.fsf.org/licensing/licenses/agpl-3.0.html
+license_files = file: LICENSE
+url = https://github.com/openfisca/openfisca-core
+keywords = benefit, microsimulation, social, tax
+description = A versatile microsimulation free software
+long_description = file: README.md, CONTRIBUTING.md, STYLEGUIDE.md, CHANGELOG.md
+classifiers =
+    Development Status :: 5 - Production/Stable
+    License :: OSI Approved :: GNU Affero General Public License v3
+    Operating System :: POSIX
+    Programming Language :: Python
+    Programming Language :: Python :: 3.6
+    Programming Language :: Python :: 3.7
+    Topic :: Scientific/Engineering :: Information Analysis
+
+[options]
+packages = find:
+package_dir = = src
+include_package_data = True
+python_requires = >= 3.6
+
+[options.packages.find]
+where = src
+
+[options.entry_points]
+console_scripts =
+    openfisca = openfisca_core.scripts.openfisca_command:main
+    openfisca-run-test = openfisca_core.scripts.openfisca_command:main
+
+[coverage:run]
+disable_warnings = module-not-measured
 
 [flake8]
+# E128/133:     We prefer hang-closing visual indents.
+# E251:         We prefer `function(x = 1)` over `function(x=1)`.
+# E501:         We do not enforce a maximum line length.
+# F403/405:     We ignore * imports.
+# W503/504:     We break lines before binary operators (Knuth's style).
 hang-closing    = true
 ignore          = E128,E251,F403,F405,E501,W503,W504
 in-place        = true
@@ -12,9 +48,9 @@ rst-roles       = any, class, exc, meth, obj
 rst-directives  = attribute
 
 [tool:pytest]
-addopts      = --showlocals --doctest-modules --disable-pytest-warnings
-testpaths    = tests
-python_files = **/*.py
+addopts         = --showlocals --doctest-modules --disable-pytest-warnings
+testpaths       = tests
+python_files    = **/*.py
 
 [mypy]
 ignore_missing_imports = True
diff --git a/setup.py b/setup.py
index 1935635464..9e4205615f 100644
--- a/setup.py
+++ b/setup.py
@@ -1,6 +1,6 @@
 #! /usr/bin/env python
 
-from setuptools import setup, find_packages
+from setuptools import setup
 
 # Please make sure to cap all dependency versions, in order to avoid unwanted
 # functional and integration breaks caused by external code updates.
@@ -36,35 +36,7 @@
 
 setup(
     name = 'OpenFisca-Core',
-    version = '35.5.3',
-    author = 'OpenFisca Team',
-    author_email = 'contact@openfisca.org',
-    classifiers = [
-        'Development Status :: 5 - Production/Stable',
-        'License :: OSI Approved :: GNU Affero General Public License v3',
-        'Operating System :: POSIX',
-        'Programming Language :: Python',
-        'Programming Language :: Python :: 3.6',
-        'Programming Language :: Python :: 3.7',
-        'Topic :: Scientific/Engineering :: Information Analysis',
-        ],
-    description = 'A versatile microsimulation free software',
-    keywords = 'benefit microsimulation social tax',
-    license = 'https://www.fsf.org/licensing/licenses/agpl-3.0.html',
-    url = 'https://github.com/openfisca/openfisca-core',
-
-    data_files = [
-        (
-            'share/openfisca/openfisca-core',
-            ['CHANGELOG.md', 'LICENSE', 'README.md'],
-            ),
-        ],
-    entry_points = {
-        'console_scripts': [
-            'openfisca=openfisca_core.scripts.openfisca_command:main',
-            'openfisca-run-test=openfisca_core.scripts.openfisca_command:main',
-            ],
-        },
+    install_requires = general_requirements,
     extras_require = {
         'web-api': api_requirements,
         'dev': dev_requirements,
@@ -72,7 +44,4 @@
             'openfisca-tracker == 0.4.0',
             ],
         },
-    include_package_data = True,  # Will read MANIFEST.in
-    install_requires = general_requirements,
-    packages = find_packages(exclude=['tests*']),
     )
diff --git a/openfisca_core/__init__.py b/src/openfisca_core/__init__.py
similarity index 100%
rename from openfisca_core/__init__.py
rename to src/openfisca_core/__init__.py
diff --git a/openfisca_core/commons/__init__.py b/src/openfisca_core/commons/__init__.py
similarity index 100%
rename from openfisca_core/commons/__init__.py
rename to src/openfisca_core/commons/__init__.py
diff --git a/openfisca_core/commons/dummy.py b/src/openfisca_core/commons/dummy.py
similarity index 100%
rename from openfisca_core/commons/dummy.py
rename to src/openfisca_core/commons/dummy.py
diff --git a/openfisca_core/commons/formulas.py b/src/openfisca_core/commons/formulas.py
similarity index 100%
rename from openfisca_core/commons/formulas.py
rename to src/openfisca_core/commons/formulas.py
diff --git a/openfisca_core/commons/misc.py b/src/openfisca_core/commons/misc.py
similarity index 100%
rename from openfisca_core/commons/misc.py
rename to src/openfisca_core/commons/misc.py
diff --git a/openfisca_core/commons/rates.py b/src/openfisca_core/commons/rates.py
similarity index 100%
rename from openfisca_core/commons/rates.py
rename to src/openfisca_core/commons/rates.py
diff --git a/openfisca_core/data_storage/__init__.py b/src/openfisca_core/data_storage/__init__.py
similarity index 100%
rename from openfisca_core/data_storage/__init__.py
rename to src/openfisca_core/data_storage/__init__.py
diff --git a/openfisca_core/data_storage/in_memory_storage.py b/src/openfisca_core/data_storage/in_memory_storage.py
similarity index 100%
rename from openfisca_core/data_storage/in_memory_storage.py
rename to src/openfisca_core/data_storage/in_memory_storage.py
diff --git a/openfisca_core/data_storage/on_disk_storage.py b/src/openfisca_core/data_storage/on_disk_storage.py
similarity index 100%
rename from openfisca_core/data_storage/on_disk_storage.py
rename to src/openfisca_core/data_storage/on_disk_storage.py
diff --git a/openfisca_core/entities/__init__.py b/src/openfisca_core/entities/__init__.py
similarity index 100%
rename from openfisca_core/entities/__init__.py
rename to src/openfisca_core/entities/__init__.py
diff --git a/openfisca_core/entities/entity.py b/src/openfisca_core/entities/entity.py
similarity index 100%
rename from openfisca_core/entities/entity.py
rename to src/openfisca_core/entities/entity.py
diff --git a/openfisca_core/entities/group_entity.py b/src/openfisca_core/entities/group_entity.py
similarity index 100%
rename from openfisca_core/entities/group_entity.py
rename to src/openfisca_core/entities/group_entity.py
diff --git a/openfisca_core/entities/helpers.py b/src/openfisca_core/entities/helpers.py
similarity index 100%
rename from openfisca_core/entities/helpers.py
rename to src/openfisca_core/entities/helpers.py
diff --git a/openfisca_core/entities/role.py b/src/openfisca_core/entities/role.py
similarity index 100%
rename from openfisca_core/entities/role.py
rename to src/openfisca_core/entities/role.py
diff --git a/openfisca_core/errors/__init__.py b/src/openfisca_core/errors/__init__.py
similarity index 100%
rename from openfisca_core/errors/__init__.py
rename to src/openfisca_core/errors/__init__.py
diff --git a/openfisca_core/errors/cycle_error.py b/src/openfisca_core/errors/cycle_error.py
similarity index 100%
rename from openfisca_core/errors/cycle_error.py
rename to src/openfisca_core/errors/cycle_error.py
diff --git a/openfisca_core/errors/empty_argument_error.py b/src/openfisca_core/errors/empty_argument_error.py
similarity index 100%
rename from openfisca_core/errors/empty_argument_error.py
rename to src/openfisca_core/errors/empty_argument_error.py
diff --git a/openfisca_core/errors/nan_creation_error.py b/src/openfisca_core/errors/nan_creation_error.py
similarity index 100%
rename from openfisca_core/errors/nan_creation_error.py
rename to src/openfisca_core/errors/nan_creation_error.py
diff --git a/openfisca_core/errors/parameter_not_found_error.py b/src/openfisca_core/errors/parameter_not_found_error.py
similarity index 100%
rename from openfisca_core/errors/parameter_not_found_error.py
rename to src/openfisca_core/errors/parameter_not_found_error.py
diff --git a/openfisca_core/errors/parameter_parsing_error.py b/src/openfisca_core/errors/parameter_parsing_error.py
similarity index 100%
rename from openfisca_core/errors/parameter_parsing_error.py
rename to src/openfisca_core/errors/parameter_parsing_error.py
diff --git a/openfisca_core/errors/period_mismatch_error.py b/src/openfisca_core/errors/period_mismatch_error.py
similarity index 100%
rename from openfisca_core/errors/period_mismatch_error.py
rename to src/openfisca_core/errors/period_mismatch_error.py
diff --git a/openfisca_core/errors/situation_parsing_error.py b/src/openfisca_core/errors/situation_parsing_error.py
similarity index 100%
rename from openfisca_core/errors/situation_parsing_error.py
rename to src/openfisca_core/errors/situation_parsing_error.py
diff --git a/openfisca_core/errors/spiral_error.py b/src/openfisca_core/errors/spiral_error.py
similarity index 100%
rename from openfisca_core/errors/spiral_error.py
rename to src/openfisca_core/errors/spiral_error.py
diff --git a/openfisca_core/errors/variable_name_config_error.py b/src/openfisca_core/errors/variable_name_config_error.py
similarity index 100%
rename from openfisca_core/errors/variable_name_config_error.py
rename to src/openfisca_core/errors/variable_name_config_error.py
diff --git a/openfisca_core/errors/variable_not_found_error.py b/src/openfisca_core/errors/variable_not_found_error.py
similarity index 100%
rename from openfisca_core/errors/variable_not_found_error.py
rename to src/openfisca_core/errors/variable_not_found_error.py
diff --git a/openfisca_core/experimental/__init__.py b/src/openfisca_core/experimental/__init__.py
similarity index 100%
rename from openfisca_core/experimental/__init__.py
rename to src/openfisca_core/experimental/__init__.py
diff --git a/openfisca_core/experimental/memory_config.py b/src/openfisca_core/experimental/memory_config.py
similarity index 100%
rename from openfisca_core/experimental/memory_config.py
rename to src/openfisca_core/experimental/memory_config.py
diff --git a/openfisca_core/formula_helpers.py b/src/openfisca_core/formula_helpers.py
similarity index 100%
rename from openfisca_core/formula_helpers.py
rename to src/openfisca_core/formula_helpers.py
diff --git a/openfisca_core/holders/__init__.py b/src/openfisca_core/holders/__init__.py
similarity index 100%
rename from openfisca_core/holders/__init__.py
rename to src/openfisca_core/holders/__init__.py
diff --git a/openfisca_core/holders/helpers.py b/src/openfisca_core/holders/helpers.py
similarity index 100%
rename from openfisca_core/holders/helpers.py
rename to src/openfisca_core/holders/helpers.py
diff --git a/openfisca_core/holders/holder.py b/src/openfisca_core/holders/holder.py
similarity index 100%
rename from openfisca_core/holders/holder.py
rename to src/openfisca_core/holders/holder.py
diff --git a/openfisca_core/indexed_enums/__init__.py b/src/openfisca_core/indexed_enums/__init__.py
similarity index 100%
rename from openfisca_core/indexed_enums/__init__.py
rename to src/openfisca_core/indexed_enums/__init__.py
diff --git a/openfisca_core/indexed_enums/config.py b/src/openfisca_core/indexed_enums/config.py
similarity index 100%
rename from openfisca_core/indexed_enums/config.py
rename to src/openfisca_core/indexed_enums/config.py
diff --git a/openfisca_core/indexed_enums/enum.py b/src/openfisca_core/indexed_enums/enum.py
similarity index 100%
rename from openfisca_core/indexed_enums/enum.py
rename to src/openfisca_core/indexed_enums/enum.py
diff --git a/openfisca_core/indexed_enums/enum_array.py b/src/openfisca_core/indexed_enums/enum_array.py
similarity index 100%
rename from openfisca_core/indexed_enums/enum_array.py
rename to src/openfisca_core/indexed_enums/enum_array.py
diff --git a/openfisca_core/memory_config.py b/src/openfisca_core/memory_config.py
similarity index 100%
rename from openfisca_core/memory_config.py
rename to src/openfisca_core/memory_config.py
diff --git a/openfisca_core/model_api.py b/src/openfisca_core/model_api.py
similarity index 100%
rename from openfisca_core/model_api.py
rename to src/openfisca_core/model_api.py
diff --git a/openfisca_core/parameters/__init__.py b/src/openfisca_core/parameters/__init__.py
similarity index 100%
rename from openfisca_core/parameters/__init__.py
rename to src/openfisca_core/parameters/__init__.py
diff --git a/openfisca_core/parameters/at_instant_like.py b/src/openfisca_core/parameters/at_instant_like.py
similarity index 100%
rename from openfisca_core/parameters/at_instant_like.py
rename to src/openfisca_core/parameters/at_instant_like.py
diff --git a/openfisca_core/parameters/config.py b/src/openfisca_core/parameters/config.py
similarity index 100%
rename from openfisca_core/parameters/config.py
rename to src/openfisca_core/parameters/config.py
diff --git a/openfisca_core/parameters/helpers.py b/src/openfisca_core/parameters/helpers.py
similarity index 100%
rename from openfisca_core/parameters/helpers.py
rename to src/openfisca_core/parameters/helpers.py
diff --git a/openfisca_core/parameters/parameter.py b/src/openfisca_core/parameters/parameter.py
similarity index 100%
rename from openfisca_core/parameters/parameter.py
rename to src/openfisca_core/parameters/parameter.py
diff --git a/openfisca_core/parameters/parameter_at_instant.py b/src/openfisca_core/parameters/parameter_at_instant.py
similarity index 100%
rename from openfisca_core/parameters/parameter_at_instant.py
rename to src/openfisca_core/parameters/parameter_at_instant.py
diff --git a/openfisca_core/parameters/parameter_node.py b/src/openfisca_core/parameters/parameter_node.py
similarity index 100%
rename from openfisca_core/parameters/parameter_node.py
rename to src/openfisca_core/parameters/parameter_node.py
diff --git a/openfisca_core/parameters/parameter_node_at_instant.py b/src/openfisca_core/parameters/parameter_node_at_instant.py
similarity index 100%
rename from openfisca_core/parameters/parameter_node_at_instant.py
rename to src/openfisca_core/parameters/parameter_node_at_instant.py
diff --git a/openfisca_core/parameters/parameter_scale.py b/src/openfisca_core/parameters/parameter_scale.py
similarity index 100%
rename from openfisca_core/parameters/parameter_scale.py
rename to src/openfisca_core/parameters/parameter_scale.py
diff --git a/openfisca_core/parameters/parameter_scale_bracket.py b/src/openfisca_core/parameters/parameter_scale_bracket.py
similarity index 100%
rename from openfisca_core/parameters/parameter_scale_bracket.py
rename to src/openfisca_core/parameters/parameter_scale_bracket.py
diff --git a/openfisca_core/parameters/values_history.py b/src/openfisca_core/parameters/values_history.py
similarity index 100%
rename from openfisca_core/parameters/values_history.py
rename to src/openfisca_core/parameters/values_history.py
diff --git a/openfisca_core/parameters/vectorial_parameter_node_at_instant.py b/src/openfisca_core/parameters/vectorial_parameter_node_at_instant.py
similarity index 100%
rename from openfisca_core/parameters/vectorial_parameter_node_at_instant.py
rename to src/openfisca_core/parameters/vectorial_parameter_node_at_instant.py
diff --git a/openfisca_core/periods/__init__.py b/src/openfisca_core/periods/__init__.py
similarity index 100%
rename from openfisca_core/periods/__init__.py
rename to src/openfisca_core/periods/__init__.py
diff --git a/openfisca_core/periods/config.py b/src/openfisca_core/periods/config.py
similarity index 100%
rename from openfisca_core/periods/config.py
rename to src/openfisca_core/periods/config.py
diff --git a/openfisca_core/periods/helpers.py b/src/openfisca_core/periods/helpers.py
similarity index 100%
rename from openfisca_core/periods/helpers.py
rename to src/openfisca_core/periods/helpers.py
diff --git a/openfisca_core/periods/instant_.py b/src/openfisca_core/periods/instant_.py
similarity index 100%
rename from openfisca_core/periods/instant_.py
rename to src/openfisca_core/periods/instant_.py
diff --git a/openfisca_core/periods/period_.py b/src/openfisca_core/periods/period_.py
similarity index 100%
rename from openfisca_core/periods/period_.py
rename to src/openfisca_core/periods/period_.py
diff --git a/openfisca_core/populations/__init__.py b/src/openfisca_core/populations/__init__.py
similarity index 100%
rename from openfisca_core/populations/__init__.py
rename to src/openfisca_core/populations/__init__.py
diff --git a/openfisca_core/populations/config.py b/src/openfisca_core/populations/config.py
similarity index 100%
rename from openfisca_core/populations/config.py
rename to src/openfisca_core/populations/config.py
diff --git a/openfisca_core/populations/group_population.py b/src/openfisca_core/populations/group_population.py
similarity index 100%
rename from openfisca_core/populations/group_population.py
rename to src/openfisca_core/populations/group_population.py
diff --git a/openfisca_core/populations/population.py b/src/openfisca_core/populations/population.py
similarity index 100%
rename from openfisca_core/populations/population.py
rename to src/openfisca_core/populations/population.py
diff --git a/openfisca_core/projectors/__init__.py b/src/openfisca_core/projectors/__init__.py
similarity index 100%
rename from openfisca_core/projectors/__init__.py
rename to src/openfisca_core/projectors/__init__.py
diff --git a/openfisca_core/projectors/entity_to_person_projector.py b/src/openfisca_core/projectors/entity_to_person_projector.py
similarity index 100%
rename from openfisca_core/projectors/entity_to_person_projector.py
rename to src/openfisca_core/projectors/entity_to_person_projector.py
diff --git a/openfisca_core/projectors/first_person_to_entity_projector.py b/src/openfisca_core/projectors/first_person_to_entity_projector.py
similarity index 100%
rename from openfisca_core/projectors/first_person_to_entity_projector.py
rename to src/openfisca_core/projectors/first_person_to_entity_projector.py
diff --git a/openfisca_core/projectors/helpers.py b/src/openfisca_core/projectors/helpers.py
similarity index 100%
rename from openfisca_core/projectors/helpers.py
rename to src/openfisca_core/projectors/helpers.py
diff --git a/openfisca_core/projectors/projector.py b/src/openfisca_core/projectors/projector.py
similarity index 100%
rename from openfisca_core/projectors/projector.py
rename to src/openfisca_core/projectors/projector.py
diff --git a/openfisca_core/projectors/unique_role_to_entity_projector.py b/src/openfisca_core/projectors/unique_role_to_entity_projector.py
similarity index 100%
rename from openfisca_core/projectors/unique_role_to_entity_projector.py
rename to src/openfisca_core/projectors/unique_role_to_entity_projector.py
diff --git a/openfisca_core/rates.py b/src/openfisca_core/rates.py
similarity index 100%
rename from openfisca_core/rates.py
rename to src/openfisca_core/rates.py
diff --git a/openfisca_core/reforms/__init__.py b/src/openfisca_core/reforms/__init__.py
similarity index 100%
rename from openfisca_core/reforms/__init__.py
rename to src/openfisca_core/reforms/__init__.py
diff --git a/openfisca_core/reforms/reform.py b/src/openfisca_core/reforms/reform.py
similarity index 100%
rename from openfisca_core/reforms/reform.py
rename to src/openfisca_core/reforms/reform.py
diff --git a/openfisca_core/scripts/__init__.py b/src/openfisca_core/scripts/__init__.py
similarity index 100%
rename from openfisca_core/scripts/__init__.py
rename to src/openfisca_core/scripts/__init__.py
diff --git a/openfisca_core/scripts/assets/__init__.py b/src/openfisca_core/scripts/assets/__init__.py
similarity index 100%
rename from openfisca_core/scripts/assets/__init__.py
rename to src/openfisca_core/scripts/assets/__init__.py
diff --git a/openfisca_core/scripts/assets/index.html b/src/openfisca_core/scripts/assets/index.html
similarity index 100%
rename from openfisca_core/scripts/assets/index.html
rename to src/openfisca_core/scripts/assets/index.html
diff --git a/openfisca_core/scripts/find_placeholders.py b/src/openfisca_core/scripts/find_placeholders.py
similarity index 100%
rename from openfisca_core/scripts/find_placeholders.py
rename to src/openfisca_core/scripts/find_placeholders.py
diff --git a/openfisca_core/scripts/measure_numpy_condition_notations.py b/src/openfisca_core/scripts/measure_numpy_condition_notations.py
similarity index 100%
rename from openfisca_core/scripts/measure_numpy_condition_notations.py
rename to src/openfisca_core/scripts/measure_numpy_condition_notations.py
diff --git a/openfisca_core/scripts/measure_performances.py b/src/openfisca_core/scripts/measure_performances.py
similarity index 100%
rename from openfisca_core/scripts/measure_performances.py
rename to src/openfisca_core/scripts/measure_performances.py
diff --git a/openfisca_core/scripts/measure_performances_fancy_indexing.py b/src/openfisca_core/scripts/measure_performances_fancy_indexing.py
similarity index 100%
rename from openfisca_core/scripts/measure_performances_fancy_indexing.py
rename to src/openfisca_core/scripts/measure_performances_fancy_indexing.py
diff --git a/openfisca_core/scripts/migrations/__init__.py b/src/openfisca_core/scripts/migrations/__init__.py
similarity index 100%
rename from openfisca_core/scripts/migrations/__init__.py
rename to src/openfisca_core/scripts/migrations/__init__.py
diff --git a/openfisca_core/scripts/migrations/v16_2_to_v17/__init__.py b/src/openfisca_core/scripts/migrations/v16_2_to_v17/__init__.py
similarity index 100%
rename from openfisca_core/scripts/migrations/v16_2_to_v17/__init__.py
rename to src/openfisca_core/scripts/migrations/v16_2_to_v17/__init__.py
diff --git a/openfisca_core/scripts/migrations/v16_2_to_v17/legislation.xsd b/src/openfisca_core/scripts/migrations/v16_2_to_v17/legislation.xsd
similarity index 100%
rename from openfisca_core/scripts/migrations/v16_2_to_v17/legislation.xsd
rename to src/openfisca_core/scripts/migrations/v16_2_to_v17/legislation.xsd
diff --git a/openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_country_template.py b/src/openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_country_template.py
similarity index 100%
rename from openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_country_template.py
rename to src/openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_country_template.py
diff --git a/openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_extension_template.py b/src/openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_extension_template.py
similarity index 100%
rename from openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_extension_template.py
rename to src/openfisca_core/scripts/migrations/v16_2_to_v17/xml_to_yaml_extension_template.py
diff --git a/openfisca_core/scripts/migrations/v24_to_25.py b/src/openfisca_core/scripts/migrations/v24_to_25.py
similarity index 100%
rename from openfisca_core/scripts/migrations/v24_to_25.py
rename to src/openfisca_core/scripts/migrations/v24_to_25.py
diff --git a/openfisca_core/scripts/openfisca_command.py b/src/openfisca_core/scripts/openfisca_command.py
similarity index 100%
rename from openfisca_core/scripts/openfisca_command.py
rename to src/openfisca_core/scripts/openfisca_command.py
diff --git a/openfisca_core/scripts/remove_fuzzy.py b/src/openfisca_core/scripts/remove_fuzzy.py
similarity index 100%
rename from openfisca_core/scripts/remove_fuzzy.py
rename to src/openfisca_core/scripts/remove_fuzzy.py
diff --git a/openfisca_core/scripts/run_test.py b/src/openfisca_core/scripts/run_test.py
similarity index 100%
rename from openfisca_core/scripts/run_test.py
rename to src/openfisca_core/scripts/run_test.py
diff --git a/openfisca_core/scripts/simulation_generator.py b/src/openfisca_core/scripts/simulation_generator.py
similarity index 100%
rename from openfisca_core/scripts/simulation_generator.py
rename to src/openfisca_core/scripts/simulation_generator.py
diff --git a/openfisca_core/simulation_builder.py b/src/openfisca_core/simulation_builder.py
similarity index 100%
rename from openfisca_core/simulation_builder.py
rename to src/openfisca_core/simulation_builder.py
diff --git a/openfisca_core/simulations/__init__.py b/src/openfisca_core/simulations/__init__.py
similarity index 100%
rename from openfisca_core/simulations/__init__.py
rename to src/openfisca_core/simulations/__init__.py
diff --git a/openfisca_core/simulations/helpers.py b/src/openfisca_core/simulations/helpers.py
similarity index 100%
rename from openfisca_core/simulations/helpers.py
rename to src/openfisca_core/simulations/helpers.py
diff --git a/openfisca_core/simulations/simulation.py b/src/openfisca_core/simulations/simulation.py
similarity index 100%
rename from openfisca_core/simulations/simulation.py
rename to src/openfisca_core/simulations/simulation.py
diff --git a/openfisca_core/simulations/simulation_builder.py b/src/openfisca_core/simulations/simulation_builder.py
similarity index 100%
rename from openfisca_core/simulations/simulation_builder.py
rename to src/openfisca_core/simulations/simulation_builder.py
diff --git a/openfisca_core/taxbenefitsystems/__init__.py b/src/openfisca_core/taxbenefitsystems/__init__.py
similarity index 100%
rename from openfisca_core/taxbenefitsystems/__init__.py
rename to src/openfisca_core/taxbenefitsystems/__init__.py
diff --git a/openfisca_core/taxbenefitsystems/tax_benefit_system.py b/src/openfisca_core/taxbenefitsystems/tax_benefit_system.py
similarity index 100%
rename from openfisca_core/taxbenefitsystems/tax_benefit_system.py
rename to src/openfisca_core/taxbenefitsystems/tax_benefit_system.py
diff --git a/openfisca_core/taxscales/__init__.py b/src/openfisca_core/taxscales/__init__.py
similarity index 100%
rename from openfisca_core/taxscales/__init__.py
rename to src/openfisca_core/taxscales/__init__.py
diff --git a/openfisca_core/taxscales/abstract_rate_tax_scale.py b/src/openfisca_core/taxscales/abstract_rate_tax_scale.py
similarity index 100%
rename from openfisca_core/taxscales/abstract_rate_tax_scale.py
rename to src/openfisca_core/taxscales/abstract_rate_tax_scale.py
diff --git a/openfisca_core/taxscales/abstract_tax_scale.py b/src/openfisca_core/taxscales/abstract_tax_scale.py
similarity index 100%
rename from openfisca_core/taxscales/abstract_tax_scale.py
rename to src/openfisca_core/taxscales/abstract_tax_scale.py
diff --git a/openfisca_core/taxscales/amount_tax_scale_like.py b/src/openfisca_core/taxscales/amount_tax_scale_like.py
similarity index 100%
rename from openfisca_core/taxscales/amount_tax_scale_like.py
rename to src/openfisca_core/taxscales/amount_tax_scale_like.py
diff --git a/openfisca_core/taxscales/helpers.py b/src/openfisca_core/taxscales/helpers.py
similarity index 100%
rename from openfisca_core/taxscales/helpers.py
rename to src/openfisca_core/taxscales/helpers.py
diff --git a/openfisca_core/taxscales/linear_average_rate_tax_scale.py b/src/openfisca_core/taxscales/linear_average_rate_tax_scale.py
similarity index 100%
rename from openfisca_core/taxscales/linear_average_rate_tax_scale.py
rename to src/openfisca_core/taxscales/linear_average_rate_tax_scale.py
diff --git a/openfisca_core/taxscales/marginal_amount_tax_scale.py b/src/openfisca_core/taxscales/marginal_amount_tax_scale.py
similarity index 100%
rename from openfisca_core/taxscales/marginal_amount_tax_scale.py
rename to src/openfisca_core/taxscales/marginal_amount_tax_scale.py
diff --git a/openfisca_core/taxscales/marginal_rate_tax_scale.py b/src/openfisca_core/taxscales/marginal_rate_tax_scale.py
similarity index 100%
rename from openfisca_core/taxscales/marginal_rate_tax_scale.py
rename to src/openfisca_core/taxscales/marginal_rate_tax_scale.py
diff --git a/openfisca_core/taxscales/rate_tax_scale_like.py b/src/openfisca_core/taxscales/rate_tax_scale_like.py
similarity index 100%
rename from openfisca_core/taxscales/rate_tax_scale_like.py
rename to src/openfisca_core/taxscales/rate_tax_scale_like.py
diff --git a/openfisca_core/taxscales/single_amount_tax_scale.py b/src/openfisca_core/taxscales/single_amount_tax_scale.py
similarity index 100%
rename from openfisca_core/taxscales/single_amount_tax_scale.py
rename to src/openfisca_core/taxscales/single_amount_tax_scale.py
diff --git a/openfisca_core/taxscales/tax_scale_like.py b/src/openfisca_core/taxscales/tax_scale_like.py
similarity index 100%
rename from openfisca_core/taxscales/tax_scale_like.py
rename to src/openfisca_core/taxscales/tax_scale_like.py
diff --git a/openfisca_core/tools/__init__.py b/src/openfisca_core/tools/__init__.py
similarity index 100%
rename from openfisca_core/tools/__init__.py
rename to src/openfisca_core/tools/__init__.py
diff --git a/openfisca_core/tools/simulation_dumper.py b/src/openfisca_core/tools/simulation_dumper.py
similarity index 100%
rename from openfisca_core/tools/simulation_dumper.py
rename to src/openfisca_core/tools/simulation_dumper.py
diff --git a/openfisca_core/tools/test_runner.py b/src/openfisca_core/tools/test_runner.py
similarity index 100%
rename from openfisca_core/tools/test_runner.py
rename to src/openfisca_core/tools/test_runner.py
diff --git a/openfisca_core/tracers/__init__.py b/src/openfisca_core/tracers/__init__.py
similarity index 100%
rename from openfisca_core/tracers/__init__.py
rename to src/openfisca_core/tracers/__init__.py
diff --git a/openfisca_core/tracers/computation_log.py b/src/openfisca_core/tracers/computation_log.py
similarity index 100%
rename from openfisca_core/tracers/computation_log.py
rename to src/openfisca_core/tracers/computation_log.py
diff --git a/openfisca_core/tracers/flat_trace.py b/src/openfisca_core/tracers/flat_trace.py
similarity index 100%
rename from openfisca_core/tracers/flat_trace.py
rename to src/openfisca_core/tracers/flat_trace.py
diff --git a/openfisca_core/tracers/full_tracer.py b/src/openfisca_core/tracers/full_tracer.py
similarity index 100%
rename from openfisca_core/tracers/full_tracer.py
rename to src/openfisca_core/tracers/full_tracer.py
diff --git a/openfisca_core/tracers/performance_log.py b/src/openfisca_core/tracers/performance_log.py
similarity index 100%
rename from openfisca_core/tracers/performance_log.py
rename to src/openfisca_core/tracers/performance_log.py
diff --git a/openfisca_core/tracers/simple_tracer.py b/src/openfisca_core/tracers/simple_tracer.py
similarity index 100%
rename from openfisca_core/tracers/simple_tracer.py
rename to src/openfisca_core/tracers/simple_tracer.py
diff --git a/openfisca_core/tracers/trace_node.py b/src/openfisca_core/tracers/trace_node.py
similarity index 100%
rename from openfisca_core/tracers/trace_node.py
rename to src/openfisca_core/tracers/trace_node.py
diff --git a/openfisca_core/tracers/tracing_parameter_node_at_instant.py b/src/openfisca_core/tracers/tracing_parameter_node_at_instant.py
similarity index 100%
rename from openfisca_core/tracers/tracing_parameter_node_at_instant.py
rename to src/openfisca_core/tracers/tracing_parameter_node_at_instant.py
diff --git a/openfisca_core/variables/__init__.py b/src/openfisca_core/variables/__init__.py
similarity index 100%
rename from openfisca_core/variables/__init__.py
rename to src/openfisca_core/variables/__init__.py
diff --git a/openfisca_core/variables/config.py b/src/openfisca_core/variables/config.py
similarity index 100%
rename from openfisca_core/variables/config.py
rename to src/openfisca_core/variables/config.py
diff --git a/openfisca_core/variables/helpers.py b/src/openfisca_core/variables/helpers.py
similarity index 100%
rename from openfisca_core/variables/helpers.py
rename to src/openfisca_core/variables/helpers.py
diff --git a/openfisca_core/variables/typing.py b/src/openfisca_core/variables/typing.py
similarity index 100%
rename from openfisca_core/variables/typing.py
rename to src/openfisca_core/variables/typing.py
diff --git a/openfisca_core/variables/variable.py b/src/openfisca_core/variables/variable.py
similarity index 100%
rename from openfisca_core/variables/variable.py
rename to src/openfisca_core/variables/variable.py
diff --git a/openfisca_core/warnings/__init__.py b/src/openfisca_core/warnings/__init__.py
similarity index 100%
rename from openfisca_core/warnings/__init__.py
rename to src/openfisca_core/warnings/__init__.py
diff --git a/openfisca_core/warnings/libyaml_warning.py b/src/openfisca_core/warnings/libyaml_warning.py
similarity index 100%
rename from openfisca_core/warnings/libyaml_warning.py
rename to src/openfisca_core/warnings/libyaml_warning.py
diff --git a/openfisca_core/warnings/memory_warning.py b/src/openfisca_core/warnings/memory_warning.py
similarity index 100%
rename from openfisca_core/warnings/memory_warning.py
rename to src/openfisca_core/warnings/memory_warning.py
diff --git a/openfisca_core/warnings/tempfile_warning.py b/src/openfisca_core/warnings/tempfile_warning.py
similarity index 100%
rename from openfisca_core/warnings/tempfile_warning.py
rename to src/openfisca_core/warnings/tempfile_warning.py
diff --git a/openfisca_web_api/__init__.py b/src/openfisca_web_api/__init__.py
similarity index 100%
rename from openfisca_web_api/__init__.py
rename to src/openfisca_web_api/__init__.py
diff --git a/openfisca_web_api/app.py b/src/openfisca_web_api/app.py
similarity index 100%
rename from openfisca_web_api/app.py
rename to src/openfisca_web_api/app.py
diff --git a/openfisca_web_api/errors.py b/src/openfisca_web_api/errors.py
similarity index 100%
rename from openfisca_web_api/errors.py
rename to src/openfisca_web_api/errors.py
diff --git a/openfisca_web_api/handlers.py b/src/openfisca_web_api/handlers.py
similarity index 100%
rename from openfisca_web_api/handlers.py
rename to src/openfisca_web_api/handlers.py
diff --git a/openfisca_web_api/loader/__init__.py b/src/openfisca_web_api/loader/__init__.py
similarity index 100%
rename from openfisca_web_api/loader/__init__.py
rename to src/openfisca_web_api/loader/__init__.py
diff --git a/openfisca_web_api/loader/entities.py b/src/openfisca_web_api/loader/entities.py
similarity index 100%
rename from openfisca_web_api/loader/entities.py
rename to src/openfisca_web_api/loader/entities.py
diff --git a/openfisca_web_api/loader/parameters.py b/src/openfisca_web_api/loader/parameters.py
similarity index 100%
rename from openfisca_web_api/loader/parameters.py
rename to src/openfisca_web_api/loader/parameters.py
diff --git a/openfisca_web_api/loader/spec.py b/src/openfisca_web_api/loader/spec.py
similarity index 100%
rename from openfisca_web_api/loader/spec.py
rename to src/openfisca_web_api/loader/spec.py
diff --git a/openfisca_web_api/loader/tax_benefit_system.py b/src/openfisca_web_api/loader/tax_benefit_system.py
similarity index 100%
rename from openfisca_web_api/loader/tax_benefit_system.py
rename to src/openfisca_web_api/loader/tax_benefit_system.py
diff --git a/openfisca_web_api/loader/variables.py b/src/openfisca_web_api/loader/variables.py
similarity index 100%
rename from openfisca_web_api/loader/variables.py
rename to src/openfisca_web_api/loader/variables.py
diff --git a/openfisca_web_api/openAPI.yml b/src/openfisca_web_api/openAPI.yml
similarity index 100%
rename from openfisca_web_api/openAPI.yml
rename to src/openfisca_web_api/openAPI.yml
diff --git a/openfisca_web_api/scripts/__init__.py b/src/openfisca_web_api/scripts/__init__.py
similarity index 100%
rename from openfisca_web_api/scripts/__init__.py
rename to src/openfisca_web_api/scripts/__init__.py
diff --git a/openfisca_web_api/scripts/serve.py b/src/openfisca_web_api/scripts/serve.py
similarity index 100%
rename from openfisca_web_api/scripts/serve.py
rename to src/openfisca_web_api/scripts/serve.py
diff --git a/tasks/dev.mk b/tasks/dev.mk
index f3b59d00cb..9bc1bc10b4 100644
--- a/tasks/dev.mk
+++ b/tasks/dev.mk
@@ -12,6 +12,7 @@ uninstall:
 ## Delete builds and compiled python files.
 clean: \
 	$(shell ls -d * | grep "build\|dist") \
+	$(shell find . -name "*.egg-info")
 	$(shell find . -name "*.pyc")
 	@$(call print_help,$@:)
 	@rm -rf $?
diff --git a/tasks/lint.mk b/tasks/lint.mk
index 8be8dd71ce..890ffeae8d 100644
--- a/tasks/lint.mk
+++ b/tasks/lint.mk
@@ -9,19 +9,19 @@ check-syntax-errors: .
 	@$(call print_pass,$@:)
 
 ## Run linters to check for syntax and style errors.
-check-style: $(shell git ls-files "*.py")
+check-style:
 	@$(call print_help,$@:)
-	@flake8 $?
+	@flake8 $(shell git ls-files "*.py")
 	@$(call print_pass,$@:)
 
 ## Run static type checkers for type errors.
-check-types: openfisca_core openfisca_web_api
+check-types:
 	@$(call print_help,$@:)
-	@mypy $?
+	@mypy src
 	@$(call print_pass,$@:)
 
 ## Run code formatters to correct style errors.
-format-style: $(shell git ls-files "*.py")
+format-style:
 	@$(call print_help,$@:)
-	@autopep8 $?
+	@autopep8 $(shell find . -name "*.py")
 	@$(call print_pass,$@:)
diff --git a/tasks/publish.mk b/tasks/publish.mk
index cf56853aea..55c48200a9 100644
--- a/tasks/publish.mk
+++ b/tasks/publish.mk
@@ -12,7 +12,7 @@ install-publisher:
 install-deps:
 	@$(call print_help,$@:)
 	@python setup.py egg_info
-	@pip install $$(grep -v "^\[" *.egg-info/requires.txt)
+	@pip install $$(grep -v "^\[" src/*.egg-info/requires.txt)
 	@$(call print_pass,$@:)
 
 ## Build & install openfisca-core for deployment and publishing.
diff --git a/tasks/test_code.mk b/tasks/test_code.mk
index 878983049d..13d88df4d6 100644
--- a/tasks/test_code.mk
+++ b/tasks/test_code.mk
@@ -15,7 +15,7 @@ test-code: test-core
 ## Run openfisca-core tests.
 test-core: $(shell git ls-files "tests/*.py")
 	@$(call print_help,$@:)
-	@PYTEST_ADDOPTS="${PYTEST_ADDOPTS} --cov=openfisca_core ${pytest_args}" \
+	@PYTEST_ADDOPTS="${PYTEST_ADDOPTS} --cov=src ${pytest_args}" \
 		openfisca test $? \
 		${openfisca_args}
 	@$(call print_pass,$@:)