diff --git a/docs/_docs/reference/newtypes.md b/docs/_docs/reference/newtypes.md
index fc786651..74d41fe7 100644
--- a/docs/_docs/reference/newtypes.md
+++ b/docs/_docs/reference/newtypes.md
@@ -94,3 +94,12 @@ val unsafeRuntime: Double =
   else throw new IllegalArgumentException("...")
 ```
 
+## New type with no constraint
+
+You can create a new type without restriction by using the [[Pure|io.github.iltotore.iron.constraint.any.Pure]]
+constraint. [[Pure|io.github.iltotore.iron.constraint.any.Pure]] is an alias for
+[[True|io.github.iltotore.iron.constraint.any.True]], a constraint that is always satisfied.
+
+```scala
+type FirstName = String :| Pure
+```
\ No newline at end of file
diff --git a/main/src/io/github/iltotore/iron/constraint/any.scala b/main/src/io/github/iltotore/iron/constraint/any.scala
index b388f55a..55b5321d 100644
--- a/main/src/io/github/iltotore/iron/constraint/any.scala
+++ b/main/src/io/github/iltotore/iron/constraint/any.scala
@@ -18,6 +18,12 @@ object any:
    */
   final class True
 
+  /**
+   * Alias for [[True]]. Usually used for new types with no constraint.
+   * @see "Creating new types" reference.
+   */
+  type Pure = True
+
   /**
    * An always-invalid constraint.
    */