diff --git a/dust-lang/src/abstract_tree/assignment.rs b/dust-lang/src/abstract_tree/assignment.rs
index 3c122a4..c245a24 100644
--- a/dust-lang/src/abstract_tree/assignment.rs
+++ b/dust-lang/src/abstract_tree/assignment.rs
@@ -7,10 +7,7 @@ use crate::{
     Context, Value,
 };
 
-use super::{
-    type_constructor::TypeInvokationConstructor, AbstractNode, Evaluation, Expression, Statement,
-    Type, TypeConstructor, WithPosition,
-};
+use super::{AbstractNode, Evaluation, Expression, Statement, Type, TypeConstructor, WithPosition};
 
 #[derive(Clone, Debug, Eq, PartialEq, PartialOrd, Ord, Serialize, Deserialize)]
 pub struct Assignment {
@@ -47,30 +44,19 @@ impl AbstractNode for Assignment {
     fn define_types(&self, context: &Context) -> Result<(), ValidationError> {
         self.statement.define_types(context)?;
 
-        let relevant_statement = self.statement.last_evaluated_statement();
-        let statement_type = if let Some(r#type) = relevant_statement.expected_type(context)? {
-            r#type
+        if let Some(constructor) = &self.constructor {
+            let r#type = constructor.construct(&context)?;
+
+            context.set_type(self.identifier.node.clone(), r#type.clone())?;
+        } else if let Some(r#type) = self.statement.expected_type(context)? {
+            context.set_type(self.identifier.node.clone(), r#type)?;
         } else {
             return Err(ValidationError::CannotAssignToNone(
                 self.statement.position(),
             ));
         };
 
-        if let Some(constructor) = &self.constructor {
-            let r#type = constructor.clone().construct(&context)?;
-
-            r#type
-                .check(&statement_type)
-                .map_err(|conflict| ValidationError::TypeCheck {
-                    conflict,
-                    actual_position: self.statement.position(),
-                    expected_position: Some(constructor.position()),
-                })?;
-
-            context.set_type(self.identifier.node.clone(), r#type.clone())?;
-        } else {
-            context.set_type(self.identifier.node.clone(), statement_type.clone())?;
-        }
+        let relevant_statement = self.statement.last_evaluated_statement();
 
         if let (Some(constructor), Statement::Expression(Expression::FunctionCall(function_call))) =
             (&self.constructor, relevant_statement)
@@ -110,40 +96,7 @@ impl AbstractNode for Assignment {
     }
 
     fn validate(&self, context: &Context, manage_memory: bool) -> Result<(), ValidationError> {
-        let relevant_statement = self.statement.last_evaluated_statement();
-        let statement_type = if let Some(r#type) = relevant_statement.expected_type(context)? {
-            r#type
-        } else {
-            return Err(ValidationError::CannotAssignToNone(
-                relevant_statement.position(),
-            ));
-        };
-
-        self.statement.validate(context, manage_memory)?;
-
-        if let (
-            Some(TypeConstructor::Invokation(TypeInvokationConstructor {
-                identifier,
-                type_arguments,
-            })),
-            Type::Enum {
-                type_parameters, ..
-            },
-        ) = (&self.constructor, &statement_type)
-        {
-            if let (Some(parameters), Some(arguments)) = (type_parameters, type_arguments) {
-                if parameters.len() != arguments.len() {
-                    return Err(ValidationError::FullTypeNotKnown {
-                        identifier: identifier.node.clone(),
-                        position: self.constructor.clone().unwrap().position(),
-                    });
-                }
-            }
-
-            return Ok(());
-        }
-
-        Ok(())
+        self.statement.validate(context, manage_memory)
     }
 
     fn evaluate(
diff --git a/dust-lang/src/abstract_tree/built_in_function.rs b/dust-lang/src/abstract_tree/built_in_function.rs
index 7f80af1..29e95f4 100644
--- a/dust-lang/src/abstract_tree/built_in_function.rs
+++ b/dust-lang/src/abstract_tree/built_in_function.rs
@@ -146,8 +146,8 @@ trait FunctionLogic {
     fn arguments(
         self,
     ) -> (
-        Option<impl IntoIterator<Item = (Identifier, TypeConstructor)>>,
-        Option<impl IntoIterator<Item = (Identifier, Expression)>>,
+        Option<impl IntoIterator<Item = Identifier>>,
+        Option<impl IntoIterator<Item = (Identifier, Type)>>,
     );
     fn return_type(&self, context: &Context) -> Result<Option<Type>, ValidationError>;
     fn call(
@@ -165,18 +165,20 @@ where
         let (type_arguments, value_arguments) = self.function.clone().arguments();
 
         if let Some(type_arguments) = type_arguments {
-            for (identifier, constructor) in type_arguments {
-                let r#type = constructor.construct(&self.context)?;
-
-                self.context.set_type(identifier, r#type)?;
+            for identifier in type_arguments {
+                self.context.set_type(
+                    identifier.clone(),
+                    Type::Generic {
+                        identifier,
+                        concrete_type: None,
+                    },
+                )?;
             }
         }
 
         if let Some(value_arguments) = value_arguments {
-            for (identifier, expression) in value_arguments {
-                if let Some(r#type) = expression.expected_type(&self.context)? {
-                    self.context.set_type(identifier, r#type)?;
-                }
+            for (identifier, r#type) in value_arguments {
+                self.context.set_type(identifier, r#type)?;
             }
         }
 
@@ -207,12 +209,12 @@ impl FunctionLogic for Length {
     fn arguments(
         self,
     ) -> (
-        Option<impl IntoIterator<Item = (Identifier, TypeConstructor)>>,
-        Option<impl IntoIterator<Item = (Identifier, Expression)>>,
+        Option<impl IntoIterator<Item = Identifier>>,
+        Option<impl IntoIterator<Item = (Identifier, Type)>>,
     ) {
         (
-            None::<array::IntoIter<(Identifier, TypeConstructor), 0>>,
-            Some([(Identifier::new("list"), *self.0)].into_iter()),
+            None::<array::IntoIter<Identifier, 0>>,
+            Some([(Identifier::new("list"), Type::ListOf(Box::new(Type::Any)))].into_iter()),
         )
     }
 
@@ -256,12 +258,12 @@ impl FunctionLogic for ReadFile {
     fn arguments(
         self,
     ) -> (
-        Option<impl IntoIterator<Item = (Identifier, TypeConstructor)>>,
-        Option<impl IntoIterator<Item = (Identifier, Expression)>>,
+        Option<impl IntoIterator<Item = Identifier>>,
+        Option<impl IntoIterator<Item = (Identifier, Type)>>,
     ) {
         (
-            None::<array::IntoIter<(Identifier, TypeConstructor), 0>>,
-            Some([(Identifier::new("path"), *self.0)].into_iter()),
+            None::<array::IntoIter<Identifier, 0>>,
+            Some([(Identifier::new("path"), Type::ListOf(Box::new(Type::Any)))].into_iter()),
         )
     }
 
@@ -291,12 +293,12 @@ impl FunctionLogic for ReadLine {
     fn arguments(
         self,
     ) -> (
-        Option<impl IntoIterator<Item = (Identifier, TypeConstructor)>>,
-        Option<impl IntoIterator<Item = (Identifier, Expression)>>,
+        Option<impl IntoIterator<Item = Identifier>>,
+        Option<impl IntoIterator<Item = (Identifier, Type)>>,
     ) {
         (
-            None::<array::IntoIter<(Identifier, TypeConstructor), 0>>,
-            None::<array::IntoIter<(Identifier, Expression), 0>>,
+            None::<array::IntoIter<Identifier, 0>>,
+            None::<array::IntoIter<(Identifier, Type), 0>>,
         )
     }
 
@@ -318,12 +320,12 @@ impl FunctionLogic for Sleep {
     fn arguments(
         self,
     ) -> (
-        Option<impl IntoIterator<Item = (Identifier, TypeConstructor)>>,
-        Option<impl IntoIterator<Item = (Identifier, Expression)>>,
+        Option<impl IntoIterator<Item = Identifier>>,
+        Option<impl IntoIterator<Item = (Identifier, Type)>>,
     ) {
         (
-            None::<array::IntoIter<(Identifier, TypeConstructor), 0>>,
-            Some([(Identifier::new("milliseconds"), *self.0)].into_iter()),
+            None::<array::IntoIter<Identifier, 0>>,
+            Some([(Identifier::new("milliseconds"), Type::Integer)].into_iter()),
         )
     }
 
@@ -343,12 +345,12 @@ impl FunctionLogic for WriteLine {
     fn arguments(
         self,
     ) -> (
-        Option<impl IntoIterator<Item = (Identifier, TypeConstructor)>>,
-        Option<impl IntoIterator<Item = (Identifier, Expression)>>,
+        Option<impl IntoIterator<Item = Identifier>>,
+        Option<impl IntoIterator<Item = (Identifier, Type)>>,
     ) {
         (
-            None::<array::IntoIter<(Identifier, TypeConstructor), 0>>,
-            Some([(Identifier::new("message"), *self.0)].into_iter()),
+            None::<array::IntoIter<Identifier, 0>>,
+            Some([(Identifier::new("message"), Type::String)].into_iter()),
         )
     }
 
@@ -378,12 +380,12 @@ impl FunctionLogic for JsonParse {
     fn arguments(
         self,
     ) -> (
-        Option<impl IntoIterator<Item = (Identifier, TypeConstructor)>>,
-        Option<impl IntoIterator<Item = (Identifier, Expression)>>,
+        Option<impl IntoIterator<Item = Identifier>>,
+        Option<impl IntoIterator<Item = (Identifier, Type)>>,
     ) {
         (
-            Some([(Identifier::new("T"), self.0)].into_iter()),
-            Some([(Identifier::new("input"), *self.1)].into_iter()),
+            Some([Identifier::new("T")].into_iter()),
+            Some([(Identifier::new("input"), Type::Any)].into_iter()),
         )
     }
 
diff --git a/std/core.ds b/std/core.ds
index 39d555f..c7b7009 100644
--- a/std/core.ds
+++ b/std/core.ds
@@ -1,3 +1,3 @@
-length = fn (input: [any]) -> int {
-	__LENGTH__ input
+length = fn (list: [any]) -> int {
+	__LENGTH__ list
 }