diff --git a/toy-impl/primitives.py b/toy-impl/primitives.py
new file mode 100644
index 0000000..635c5de
--- /dev/null
+++ b/toy-impl/primitives.py
@@ -0,0 +1,69 @@
+from type_def import *
+
+types = {
+    'int32': PrimitiveType('int32'),
+    'int64': PrimitiveType('int64'),
+    'float': PrimitiveType('float'),
+    'bool': PrimitiveType('bool')
+}
+
+i32 = types['int32']
+i64 = types['int64']
+f32 = types['float']
+b = types['bool']
+I = TypeVariable('I', [i32, i64, f32])
+
+def impl_math(ty):
+    ty.methods['__add__'] = ([SelfType(), ty], ty, set())
+    ty.methods['__sub__'] = ([SelfType(), ty], ty, set())
+    ty.methods['__mul__'] = ([SelfType(), ty], ty, set())
+    ty.methods['__neg__'] = ([SelfType()], ty, set())
+    ty.methods['__truediv__'] = ([SelfType(), ty], f32, set())
+    ty.methods['__floordiv__'] = ([SelfType(), ty], ty, set())
+    ty.methods['__mod__'] = ([SelfType(), ty], ty, set())
+    ty.methods['__pow__'] = ([SelfType(), ty], ty, set())
+
+def impl_bits(ty):
+    ty.methods['__lshift__'] = ([SelfType(), i32], ty, set())
+    ty.methods['__rshift__'] = ([SelfType(), i32], ty, set())
+    ty.methods['__xor__'] = ([SelfType(), ty], ty, set())
+
+def impl_logic(ty):
+    ty.methods['__and__'] = ([SelfType(), ty], ty, set())
+    ty.methods['__or__'] = ([SelfType(), ty], ty, set())
+
+def impl_eq(ty):
+    ty.methods['__eq__'] = ([SelfType(), ty], b, set())
+    ty.methods['__ne__'] = ([SelfType(), ty], b, set())
+
+def impl_order(ty):
+    ty.methods['__lt__'] = ([SelfType(), ty], b, set())
+    ty.methods['__gt__'] = ([SelfType(), ty], b, set())
+    ty.methods['__le__'] = ([SelfType(), ty], b, set())
+    ty.methods['__ge__'] = ([SelfType(), ty], b, set())
+
+impl_logic(b)
+impl_eq(b)
+
+impl_math(i32)
+impl_bits(i32)
+impl_logic(i32)
+impl_eq(i32)
+impl_order(i32)
+
+impl_math(i64)
+impl_bits(i64)
+impl_logic(i64)
+impl_eq(i64)
+impl_order(i64)
+
+impl_math(f32)
+impl_eq(f32)
+impl_order(f32)
+
+i32.methods['__init__'] = ([SelfType(), I], None, {'I'})
+i64.methods['__init__'] = ([SelfType(), I], None, {'I'})
+f32.methods['__init__'] = ([SelfType(), I], None, {'I'})
+
+simplest_ctx = Context({}, types)
+