diff --git a/pyproject.toml b/pyproject.toml
new file mode 100644
index 0000000..24dcec7
--- /dev/null
+++ b/pyproject.toml
@@ -0,0 +1,30 @@
+[build-system]
+requires = ["setuptools", "wheel"]
+build-backend = "setuptools.build_meta"
+
+[project]
+name = "sunfish"
+version = "1.0.0"
+description = "Sunfish: a Python Chess Engine in 111 lines of code"
+authors = [
+    { name = "Thomas Ahle", email = "thomasahle@example.com" }
+]
+readme = "README.md"
+license = { text = "GNU GPL v3" }
+requires-python = ">=3.6"
+classifiers = [
+    "Programming Language :: Python :: 3",
+    "License :: OSI Approved :: GNU General Public License v3 (GPLv3)",
+    "Operating System :: OS Independent",
+]
+
+[tool.setuptools]
+packages = ["sunfish"]
+
+[tool.setuptools.package-dir]
+"sunfish" = "src"
+
+[tool.setuptools.package-data]
+"sunfish"= ["**/*"]
+
+
diff --git a/.github/workflows/python-app.yml b/src/.github/workflows/python-app.yml
similarity index 100%
rename from .github/workflows/python-app.yml
rename to src/.github/workflows/python-app.yml
diff --git a/.gitignore b/src/.gitignore
similarity index 100%
rename from .gitignore
rename to src/.gitignore
diff --git a/LICENSE.md b/src/LICENSE.md
similarity index 100%
rename from LICENSE.md
rename to src/LICENSE.md
diff --git a/README.md b/src/README.md
similarity index 100%
rename from README.md
rename to src/README.md
diff --git a/src/__init__.py b/src/__init__.py
new file mode 100644
index 0000000..caeb4d3
--- /dev/null
+++ b/src/__init__.py
@@ -0,0 +1,3 @@
+from . import sunfish
+from . import tools
+
diff --git a/build/clean.sh b/src/build/clean.sh
similarity index 100%
rename from build/clean.sh
rename to src/build/clean.sh
diff --git a/build/pack.sh b/src/build/pack.sh
similarity index 100%
rename from build/pack.sh
rename to src/build/pack.sh
diff --git a/build/pack_nnue.sh b/src/build/pack_nnue.sh
similarity index 100%
rename from build/pack_nnue.sh
rename to src/build/pack_nnue.sh
diff --git a/docs/logo/sunfish_large.png b/src/docs/logo/sunfish_large.png
similarity index 100%
rename from docs/logo/sunfish_large.png
rename to src/docs/logo/sunfish_large.png
diff --git a/docs/logo/sunfish_small.bmp b/src/docs/logo/sunfish_small.bmp
similarity index 100%
rename from docs/logo/sunfish_small.bmp
rename to src/docs/logo/sunfish_small.bmp
diff --git a/docs/sunfish.6 b/src/docs/sunfish.6
similarity index 100%
rename from docs/sunfish.6
rename to src/docs/sunfish.6
diff --git a/nnue/models/color.pickle b/src/nnue/models/color.pickle
similarity index 100%
rename from nnue/models/color.pickle
rename to src/nnue/models/color.pickle
diff --git a/nnue/models/color2.pickle b/src/nnue/models/color2.pickle
similarity index 100%
rename from nnue/models/color2.pickle
rename to src/nnue/models/color2.pickle
diff --git a/nnue/models/color2_v2.pickle b/src/nnue/models/color2_v2.pickle
similarity index 100%
rename from nnue/models/color2_v2.pickle
rename to src/nnue/models/color2_v2.pickle
diff --git a/nnue/models/color2_v3.pickle b/src/nnue/models/color2_v3.pickle
similarity index 100%
rename from nnue/models/color2_v3.pickle
rename to src/nnue/models/color2_v3.pickle
diff --git a/nnue/models/model.pickle b/src/nnue/models/model.pickle
similarity index 100%
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similarity index 100%
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diff --git a/nnue/models/model_39.pickle b/src/nnue/models/model_39.pickle
similarity index 100%
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diff --git a/nnue/models/model_59.pickle b/src/nnue/models/model_59.pickle
similarity index 100%
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similarity index 100%
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similarity index 100%
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similarity index 100%
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similarity index 100%
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similarity index 100%
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similarity index 100%
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similarity index 100%
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similarity index 100%
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diff --git a/nnue/nnue_bug_fens b/src/nnue/nnue_bug_fens
similarity index 100%
rename from nnue/nnue_bug_fens
rename to src/nnue/nnue_bug_fens
diff --git a/nnue/speed_tests.py b/src/nnue/speed_tests.py
similarity index 100%
rename from nnue/speed_tests.py
rename to src/nnue/speed_tests.py
diff --git a/nnue/sunfish2.py b/src/nnue/sunfish2.py
similarity index 100%
rename from nnue/sunfish2.py
rename to src/nnue/sunfish2.py
diff --git a/nnue/sunfish_king.py b/src/nnue/sunfish_king.py
similarity index 100%
rename from nnue/sunfish_king.py
rename to src/nnue/sunfish_king.py
diff --git a/requirements.txt b/src/requirements.txt
similarity index 100%
rename from requirements.txt
rename to src/requirements.txt
diff --git a/sunfish.py b/src/sunfish.py
similarity index 92%
rename from sunfish.py
rename to src/sunfish.py
index 0c43388..6fb712c 100755
--- a/sunfish.py
+++ b/src/sunfish.py
@@ -450,51 +450,54 @@ def render(i):
 #input = raw_input
 
 # minifier-hide start
-import sys, tools.uci
-tools.uci.run(sys.modules[__name__], hist[-1])
-sys.exit()
-# minifier-hide end
+if __name__ == "__main__":
+    print('aaa')
+    import sys, tools.uci
+    tools.uci.run(sys.modules[__name__], hist[-1])
+    sys.exit()
 
-searcher = Searcher()
-while True:
-    args = input().split()
-    if args[0] == "uci":
-        print("id name", version)
-        print("uciok")
-
-    elif args[0] == "isready":
-        print("readyok")
-
-    elif args[0] == "quit":
-        break
-
-    elif args[:2] == ["position", "startpos"]:
-        del hist[1:]
-        for ply, move in enumerate(args[3:]):
-            i, j, prom = parse(move[:2]), parse(move[2:4]), move[4:].upper()
-            if ply % 2 == 1:
-                i, j = 119 - i, 119 - j
-            hist.append(hist[-1].move(Move(i, j, prom)))
-
-    elif args[0] == "go":
-        wtime, btime, winc, binc = [int(a) / 1000 for a in args[2::2]]
-        if len(hist) % 2 == 0:
-            wtime, winc = btime, binc
-        think = min(wtime / 40 + winc, wtime / 2 - 1)
-
-        start = time.time()
-        move_str = None
-        for depth, gamma, score, move in Searcher().search(hist):
-            # The only way we can be sure to have the real move in tp_move,
-            # is if we have just failed high.
-            if score >= gamma:
-                i, j = move.i, move.j
-                if len(hist) % 2 == 0:
+# minifier-hide end
+if 0:
+    searcher = Searcher()
+    while True:
+        args = input().split()
+        if args[0] == "uci":
+            print("id name", version)
+            print("uciok")
+
+        elif args[0] == "isready":
+            print("readyok")
+
+        elif args[0] == "quit":
+            break
+
+        elif args[:2] == ["position", "startpos"]:
+            del hist[1:]
+            for ply, move in enumerate(args[3:]):
+                i, j, prom = parse(move[:2]), parse(move[2:4]), move[4:].upper()
+                if ply % 2 == 1:
                     i, j = 119 - i, 119 - j
-                move_str = render(i) + render(j) + move.prom.lower()
-                print("info depth", depth, "score cp", score, "pv", move_str)
-            if move_str and time.time() - start > think * 0.8:
-                break
+                hist.append(hist[-1].move(Move(i, j, prom)))
+
+        elif args[0] == "go":
+            wtime, btime, winc, binc = [int(a) / 1000 for a in args[2::2]]
+            if len(hist) % 2 == 0:
+                wtime, winc = btime, binc
+            think = min(wtime / 40 + winc, wtime / 2 - 1)
+
+            start = time.time()
+            move_str = None
+            for depth, gamma, score, move in Searcher().search(hist):
+                # The only way we can be sure to have the real move in tp_move,
+                # is if we have just failed high.
+                if score >= gamma:
+                    i, j = move.i, move.j
+                    if len(hist) % 2 == 0:
+                        i, j = 119 - i, 119 - j
+                    move_str = render(i) + render(j) + move.prom.lower()
+                    print("info depth", depth, "score cp", score, "pv", move_str)
+                if move_str and time.time() - start > think * 0.8:
+                    break
 
-        print("bestmove", move_str or '(none)')
+            print("bestmove", move_str or '(none)')
 
diff --git a/sunfish_nnue.py b/src/sunfish_nnue.py
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