diff --git a/poetry/core/packages/dependency.py b/poetry/core/packages/dependency.py
index 6a25ccdf9..c648a4b6a 100755
--- a/poetry/core/packages/dependency.py
+++ b/poetry/core/packages/dependency.py
@@ -44,13 +44,8 @@ def __init__(
             features=extras,
         )
 
-        try:
-            if not isinstance(constraint, VersionConstraint):
-                self._constraint = parse_constraint(constraint)
-            else:
-                self._constraint = constraint
-        except ValueError:
-            self._constraint = parse_constraint("*")
+        self._constraint = None
+        self.set_constraint(constraint=constraint)
 
         self._pretty_constraint = str(constraint)
         self._optional = optional
@@ -86,6 +81,15 @@ def name(self):
     def constraint(self):
         return self._constraint
 
+    def set_constraint(self, constraint):
+        try:
+            if not isinstance(constraint, VersionConstraint):
+                self._constraint = parse_constraint(constraint)
+            else:
+                self._constraint = constraint
+        except ValueError:
+            self._constraint = parse_constraint("*")
+
     @property
     def pretty_constraint(self):
         return self._pretty_constraint
diff --git a/pyproject.toml b/pyproject.toml
index 4e77b7945..30bb53108 100644
--- a/pyproject.toml
+++ b/pyproject.toml
@@ -53,9 +53,6 @@ vendoring = {version = "^0.3", python = "~3.8"}
 pep517 = "^0.8.2"
 "backports.tempfile" = {version = "^1.0", python = "~2.7"}
 
-[tool.intreehooks]
-build-backend = "poetry.core.masonry.api"
-
 [tool.black]
 line-length = 88
 include = '\.pyi?$'
@@ -119,5 +116,6 @@ appdirs = []
 pyrsistent = "https://raw.githubusercontent.com/tobgu/pyrsistent/master/LICENCE.mit"
 
 [build-system]
-requires = ["intreehooks"]
-build-backend = "intreehooks:loader"
+requires = ["poetry-core"]
+build-backend = "poetry.core.masonry.api"
+backend-path = ["."]