diff --git a/.github/workflows/publish.yml b/.github/workflows/publish.yml
new file mode 100644
index 0000000..f15ca7d
--- /dev/null
+++ b/.github/workflows/publish.yml
@@ -0,0 +1,24 @@
+name: Publish to PyPI
+
+on:
+  release:
+    types: [created]
+
+jobs:
+  deploy:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python
+      uses: actions/setup-python@v2
+      with:
+        python-version: "3.8"
+    - name: Install dependencies
+      run: |
+        pip install --upgrade pip==20.2.4 poetry==1.1.4
+        poetry config virtualenvs.create false
+        poetry install
+    - name: Build and publish
+      run: |
+        poetry config pypi-token.pypi ${{ secrets.PYPI_TOKEN }}
+        poetry publish --build
diff --git a/.github/workflows/test.yml b/.github/workflows/test.yml
new file mode 100644
index 0000000..be7f811
--- /dev/null
+++ b/.github/workflows/test.yml
@@ -0,0 +1,29 @@
+name: Tests
+
+on: push
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    strategy:
+      max-parallel: 4
+      matrix:
+        python-version: [3.6, 3.7, 3.8]
+
+    steps:
+    - uses: actions/checkout@v2
+    - name: Set up Python ${{ matrix.python-version }}
+      uses: actions/setup-python@v2
+      with:
+        python-version: ${{ matrix.python-version }}
+    - name: Install dependencies
+      run: |
+        pip install --upgrade pip==20.2.4 poetry==1.1.4
+        poetry config virtualenvs.create false
+        poetry install
+    - name: Check formatting
+      run: black --check ./
+    - name: Check typings
+      run: mypy *.py
+    - name: Test with pytest
+      run: pytest ./
diff --git a/poetry.lock b/poetry.lock
new file mode 100644
index 0000000..2c98468
--- /dev/null
+++ b/poetry.lock
@@ -0,0 +1,415 @@
+[[package]]
+category = "dev"
+description = "A small Python module for determining appropriate platform-specific dirs, e.g. a \"user data dir\"."
+name = "appdirs"
+optional = false
+python-versions = "*"
+version = "1.4.4"
+
+[[package]]
+category = "dev"
+description = "Atomic file writes."
+marker = "sys_platform == \"win32\""
+name = "atomicwrites"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "1.4.0"
+
+[[package]]
+category = "dev"
+description = "Classes Without Boilerplate"
+name = "attrs"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "20.2.0"
+
+[package.extras]
+dev = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface", "sphinx", "sphinx-rtd-theme", "pre-commit"]
+docs = ["sphinx", "sphinx-rtd-theme", "zope.interface"]
+tests = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six", "zope.interface"]
+tests_no_zope = ["coverage (>=5.0.2)", "hypothesis", "pympler", "pytest (>=4.3.0)", "six"]
+
+[[package]]
+category = "dev"
+description = "The uncompromising code formatter."
+name = "black"
+optional = false
+python-versions = ">=3.6"
+version = "20.8b1"
+
+[package.dependencies]
+appdirs = "*"
+click = ">=7.1.2"
+mypy-extensions = ">=0.4.3"
+pathspec = ">=0.6,<1"
+regex = ">=2020.1.8"
+toml = ">=0.10.1"
+typed-ast = ">=1.4.0"
+typing-extensions = ">=3.7.4"
+
+[package.dependencies.dataclasses]
+python = "<3.7"
+version = ">=0.6"
+
+[package.extras]
+colorama = ["colorama (>=0.4.3)"]
+d = ["aiohttp (>=3.3.2)", "aiohttp-cors"]
+
+[[package]]
+category = "dev"
+description = "Composable command line interface toolkit"
+name = "click"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+version = "7.1.2"
+
+[[package]]
+category = "dev"
+description = "Cross-platform colored terminal text."
+marker = "sys_platform == \"win32\""
+name = "colorama"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+version = "0.4.4"
+
+[[package]]
+category = "dev"
+description = "A backport of the dataclasses module for Python 3.6"
+marker = "python_version < \"3.7\""
+name = "dataclasses"
+optional = false
+python-versions = "*"
+version = "0.6"
+
+[[package]]
+category = "dev"
+description = "Read metadata from Python packages"
+marker = "python_version < \"3.8\""
+name = "importlib-metadata"
+optional = false
+python-versions = "!=3.0.*,!=3.1.*,!=3.2.*,!=3.3.*,!=3.4.*,>=2.7"
+version = "2.0.0"
+
+[package.dependencies]
+zipp = ">=0.5"
+
+[package.extras]
+docs = ["sphinx", "rst.linker"]
+testing = ["packaging", "pep517", "importlib-resources (>=1.3)"]
+
+[[package]]
+category = "dev"
+description = "iniconfig: brain-dead simple config-ini parsing"
+name = "iniconfig"
+optional = false
+python-versions = "*"
+version = "1.1.1"
+
+[[package]]
+category = "dev"
+description = "Optional static typing for Python"
+name = "mypy"
+optional = false
+python-versions = ">=3.5"
+version = "0.790"
+
+[package.dependencies]
+mypy-extensions = ">=0.4.3,<0.5.0"
+typed-ast = ">=1.4.0,<1.5.0"
+typing-extensions = ">=3.7.4"
+
+[package.extras]
+dmypy = ["psutil (>=4.0)"]
+
+[[package]]
+category = "dev"
+description = "Experimental type system extensions for programs checked with the mypy typechecker."
+name = "mypy-extensions"
+optional = false
+python-versions = "*"
+version = "0.4.3"
+
+[[package]]
+category = "dev"
+description = "Core utilities for Python packages"
+name = "packaging"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "20.4"
+
+[package.dependencies]
+pyparsing = ">=2.0.2"
+six = "*"
+
+[[package]]
+category = "dev"
+description = "Utility library for gitignore style pattern matching of file paths."
+name = "pathspec"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*, !=3.4.*"
+version = "0.8.0"
+
+[[package]]
+category = "dev"
+description = "plugin and hook calling mechanisms for python"
+name = "pluggy"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "0.13.1"
+
+[package.dependencies]
+[package.dependencies.importlib-metadata]
+python = "<3.8"
+version = ">=0.12"
+
+[package.extras]
+dev = ["pre-commit", "tox"]
+
+[[package]]
+category = "dev"
+description = "library with cross-python path, ini-parsing, io, code, log facilities"
+name = "py"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*, !=3.3.*"
+version = "1.9.0"
+
+[[package]]
+category = "dev"
+description = "Python parsing module"
+name = "pyparsing"
+optional = false
+python-versions = ">=2.6, !=3.0.*, !=3.1.*, !=3.2.*"
+version = "2.4.7"
+
+[[package]]
+category = "dev"
+description = "pytest: simple powerful testing with Python"
+name = "pytest"
+optional = false
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+
+[package.dependencies]
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+
+[package.dependencies.importlib-metadata]
+python = "<3.8"
+version = ">=0.12"
+
+[package.extras]
+checkqa_mypy = ["mypy (0.780)"]
+testing = ["argcomplete", "hypothesis (>=3.56)", "mock", "nose", "requests", "xmlschema"]
+
+[[package]]
+category = "dev"
+description = "Alternative regular expression module, to replace re."
+name = "regex"
+optional = false
+python-versions = "*"
+version = "2020.10.23"
+
+[[package]]
+category = "dev"
+description = "Python 2 and 3 compatibility utilities"
+name = "six"
+optional = false
+python-versions = ">=2.7, !=3.0.*, !=3.1.*, !=3.2.*"
+version = "1.15.0"
+
+[[package]]
+category = "dev"
+description = "Python Library for Tom's Obvious, Minimal Language"
+name = "toml"
+optional = false
+python-versions = "*"
+version = "0.10.1"
+
+[[package]]
+category = "dev"
+description = "a fork of Python 2 and 3 ast modules with type comment support"
+name = "typed-ast"
+optional = false
+python-versions = "*"
+version = "1.4.1"
+
+[[package]]
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+name = "typing-extensions"
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+
+[[package]]
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+marker = "python_version < \"3.8\""
+name = "zipp"
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+version = "3.4.0"
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+[package.extras]
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+
+[metadata]
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diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..c399b13
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,18 @@
+[tool.poetry]
+name = "sec"
+version = "0.3.0"
+description = "Tiny Python library for secrets"
+authors = ["Paris Kasidiaris <paris@sourcelair.com>"]
+license = "MIT"
+
+[tool.poetry.dependencies]
+python = "^3.6"
+
+[tool.poetry.dev-dependencies]
+black = "^20.8b1"
+pytest = "^6.1.1"
+mypy = "^0.790"
+
+[build-system]
+requires = ["poetry>=0.12"]
+build-backend = "poetry.masonry.api"
diff --git a/sec.py b/sec.py
index 4eeb609..c729c8f 100644
--- a/sec.py
+++ b/sec.py
@@ -1,7 +1,14 @@
+from typing import Optional
 import os
 
 
-def _load_secret_from_path(path: str) -> str:
+def _sanitize_environment_variable_name(name: str) -> str:
+    uppercase_name = name.upper()
+    sanitized_name = uppercase_name.replace("/", "_")
+    return sanitized_name
+
+
+def _load_secret_from_path(path: str) -> Optional[str]:
     if not os.path.exists(path):
         return None
 
@@ -9,24 +16,24 @@ def _load_secret_from_path(path: str) -> str:
         return secret_file.read().strip()
 
 
-def _load_from_run_secrets(name: str) -> str:
+def _load_from_run_secrets(name: str) -> Optional[str]:
     lowercase_name = name.lower()
     path = f"/run/secrets/{lowercase_name}"
     return _load_secret_from_path(path)
 
 
-def _load_from_environment_hint(name: str) -> str:
+def _load_from_environment_hint(name: str) -> Optional[str]:
     uppercase_name = name.upper()
     path = os.getenv(f"{uppercase_name}_FILE")
     return _load_secret_from_path(path) if path else None
 
 
-def _load_from_environment_variable(name: str) -> str:
-    uppercase_name = name.upper()
-    return os.getenv(uppercase_name)
+def _load_from_environment_variable(name: str) -> Optional[str]:
+    sanitized_name = _sanitize_environment_variable_name(name)
+    return os.getenv(sanitized_name)
 
 
-def load(name: str, fallback: str = None) -> str:
+def load(name: str, fallback: str = None) -> Optional[str]:
     """
     Searches for and returns the first secret that matches the following
     criteria in the order described:
diff --git a/setup.py b/setup.py
deleted file mode 100644
index 24e717e..0000000
--- a/setup.py
+++ /dev/null
@@ -1,24 +0,0 @@
-from setuptools import setup
-
-setup(
-    name="sec",
-    version="0.2.2",
-    description=(
-        "Simple library for working with secrets in both files and "
-        "environment variables."
-    ),
-    py_modules=["sec"],
-    url="https://github.com/sourcelair/sec",
-    author="Antonis Kalipetis, Paris Kasidiaris",
-    author_email="accounts@sourcelair.com",
-    license="MIT",
-    classifiers=[
-        "Development Status :: 5 - Production/Stable",
-        "Intended Audience :: Developers",
-        "Topic :: Software Development",
-        "License :: OSI Approved :: MIT License",
-        "Programming Language :: Python :: 3",
-        "Programming Language :: Python :: 3.6",
-    ],
-    keywords="secrets development",
-)
diff --git a/test_sec.py b/test_sec.py
index b926604..f35b589 100644
--- a/test_sec.py
+++ b/test_sec.py
@@ -63,17 +63,18 @@ def test_load_from_environment_hint():
 def test_load_from_environment_variable():
     """
     Make sure that the `_load_from_environment_variable` function returns the
-    contents of the corresponding environment variable, after uppercasing the
+    contents of the corresponding environment variable, after sanitising the
     name of the secret.
     """
-    secret_name = "database_url"
-    uppercase_secret_name = secret_name.upper()
+    environment_variable_name = "DATABASE_URL"
     secret = "postgres://USER:PASSWORD@HOST:PORT/NAME"
 
-    assert sec._load_from_environment_variable(secret_name) is None
+    assert sec._load_from_environment_variable(environment_variable_name) is None
 
-    os.environ[uppercase_secret_name] = secret
-    assert sec._load_from_environment_variable(secret_name) == secret
+    os.environ[environment_variable_name] = secret
+    assert sec._load_from_environment_variable("DATABASE_URL") == secret
+    assert sec._load_from_environment_variable("database_url") == secret
+    assert sec._load_from_environment_variable("database/url") == secret
 
 
 def test_load():