diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..374b58c
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,6 @@
+[build-system]
+requires = [
+    "setuptools>=42",
+    "wheel"
+]
+build-backend = "setuptools.build_meta"
diff --git a/setup.py b/setup.py
index 0192bbf..f5bbd23 100644
--- a/setup.py
+++ b/setup.py
@@ -7,7 +7,7 @@
 
 setuptools.setup(
     name="orffinder",
-    version="1.1",
+    version="1.2",
     author="ChocoParrot",
     author_email="lachocoparrot@gmail.com",
     description="ORFFinder API.",
@@ -17,10 +17,12 @@
     project_urls={
         "Bug Tracker": "https://github.com/Chokyotager/ORFFinder/issues",
     },
-    packages=setuptools.find_packages("src/"),
     classifiers=(
         "Programming Language :: Python :: 3",
         "License :: OSI Approved :: MIT License",
         "Operating System :: OS Independent",
     ),
+    package_dir={"": "src"},
+    packages=setuptools.find_packages(where="src"),
+    python_requires=">=3.6"
 )
diff --git a/orffinder/__init__.py b/src/orffinder/__init__.py
similarity index 100%
rename from orffinder/__init__.py
rename to src/orffinder/__init__.py
diff --git a/orffinder/orffinder.py b/src/orffinder/orffinder.py
similarity index 100%
rename from orffinder/orffinder.py
rename to src/orffinder/orffinder.py
diff --git a/orffinder/tests/__init__.py b/tests/__init__.py
similarity index 100%
rename from orffinder/tests/__init__.py
rename to tests/__init__.py
diff --git a/orffinder/tests/gene.fasta b/tests/gene.fasta
similarity index 100%
rename from orffinder/tests/gene.fasta
rename to tests/gene.fasta
diff --git a/orffinder/tests/test.py b/tests/test_orffinder.py
similarity index 95%
rename from orffinder/tests/test.py
rename to tests/test_orffinder.py
index 5229dd8..4afcc21 100644
--- a/orffinder/tests/test.py
+++ b/tests/test_orffinder.py
@@ -1,6 +1,7 @@
 from Bio import SeqIO
 from Bio.Seq import Seq
 
+from unittest import TestCase
 import orffinder
 
 sequence = list(SeqIO.parse("tests/gene.fasta", "fasta"))[0]