diff --git a/crates/kind-fmt/src/expr.rs b/crates/kind-fmt/src/expr.rs
new file mode 100644
index 00000000..f591e5d4
--- /dev/null
+++ b/crates/kind-fmt/src/expr.rs
@@ -0,0 +1,15 @@
+use kind_syntax::concrete::Expr;
+use crate::{Result, FmtContext};
+
+impl<'a> FmtContext<'a> {
+    pub fn expr(&mut self) -> Result<Expr> {
+        match self.kind() {
+            "call" => {
+                let callee = self.property("callee").unwrap();
+
+                self.cursor(callee).primary()
+            },
+            kind => todo!("{}", kind),
+        }
+    }
+}
\ No newline at end of file
diff --git a/crates/kind-fmt/src/lib.rs b/crates/kind-fmt/src/lib.rs
index 11b92116..95732f3f 100644
--- a/crates/kind-fmt/src/lib.rs
+++ b/crates/kind-fmt/src/lib.rs
@@ -1,19 +1,33 @@
-use std::path::PathBuf;
+use thin_vec::ThinVec;
+use tree_sitter::{Node, Parser, Tree, TreeCursor};
 
-use thin_vec::{thin_vec, ThinVec};
-use tree_sitter::{Parser, Tree, TreeCursor};
+use kind_syntax::concrete::Module;
+use kind_syntax::lexemes::Token;
 
-use kind_syntax::concrete::{Block, ConstructorExpr, Expr, ExprKind, LocalExpr, Module, Pat, PatKind, Rule, Signature, Stmt, TopLevel, TopLevelKind};
-use kind_syntax::lexemes::{Brace, Colon, Equal, Ident, Item, Name, Span, Token, Tokenized};
+mod expr;
+mod name;
+mod parameter;
+mod pattern;
+mod primary;
+mod statements;
+mod top_level;
 
 #[derive(Debug)]
 pub enum FmtError {
     IoError(std::io::Error),
+    Utf8Error(std::str::Utf8Error),
     TreeSitterLanguageError(tree_sitter::LanguageError),
     TreeSitterQueryError(tree_sitter::QueryError),
     UnknownParseError,
 }
 
+#[derive(Clone, Copy)]
+pub struct FmtContext<'a> {
+    pub file: &'a str,
+    pub tree: &'a Tree,
+    pub cursor: *mut TreeCursor<'a>,
+}
+
 pub type Result<T> = std::result::Result<T, FmtError>;
 
 pub fn run_fmt(string: String) -> Result<Module> {
@@ -21,7 +35,7 @@ pub fn run_fmt(string: String) -> Result<Module> {
     parser
         .set_language(tree_sitter_kind::language())
         .map_err(FmtError::TreeSitterLanguageError)?;
-    let tree = parser
+    let mut tree = parser
         .parse(string.as_bytes(), None)
         .ok_or(FmtError::UnknownParseError)?;
 
@@ -29,10 +43,16 @@ pub fn run_fmt(string: String) -> Result<Module> {
 
     let mut cursor = tree.root_node().walk();
 
-    let declarations = tree.root_node().children(&mut cursor)
-        .map(|node| {
-            specialize_top_level(&string, &tree, &mut node.walk())
-        })
+    let context = FmtContext {
+        file: &string,
+        tree: &tree,
+        cursor: &mut cursor,
+    };
+
+    let declarations = tree
+        .root_node()
+        .children(&mut cursor)
+        .map(|node| context.cursor(node).top_level())
         .collect::<Result<ThinVec<_>>>()?;
 
     Ok(Module {
@@ -42,132 +62,91 @@ pub fn run_fmt(string: String) -> Result<Module> {
     })
 }
 
-fn specialize_top_level(file: &String, tree: &Tree, cursor: &mut TreeCursor) -> Result<TopLevel> {
-    let node = cursor.node();
-    match node.kind() {
-        "val_declaration" => {
-            let name = node.child_by_field_name("name").unwrap();
-            let return_type = node.child_by_field_name("return_type");
-            let value = node.child_by_field_name("value");
+impl<'a> FmtContext<'a> {
+    pub fn node(&self) -> Node<'a> {
+        unsafe { (*self.cursor).node() }
+    }
 
-            Ok(TopLevel {
-                data: Item::new(
-                    Span::default(),
-                    TopLevelKind::Signature(Signature {
-                        name: specialize_name(file, tree, &mut name.walk())?,
-                        arguments: thin_vec![],
-                        return_type: return_type.map_or(Ok(None), |node| {
-                            let expr = specialize_expr(file, tree, &mut node.walk())?;
-                            Ok(Some(Colon(Token::default(), expr)))
-                        })?,
-                        value: value.map_or(Ok(None), |node| {
-                            let block = specialize_statements(file, tree, &mut node.walk())?;
-                            Ok(Some(block))
-                        })?,
-                    }),
-                ),
-                attributes: thin_vec![],
+    pub fn get_current_cursor(&self) -> TreeCursor<'a> {
+        unsafe { (*self.cursor).clone() }
+    }
+
+    pub fn kind(&self) -> &'static str {
+        self.node().kind()
+    }
+
+    pub fn first(&self) -> Option<Node<'a>> {
+        self.node().child(0)
+    }
+
+    pub fn at(&self, at: usize) -> Option<Node<'a>> {
+        self.node().child(at)
+    }
+
+    pub fn named_at(&self, at: usize) -> Option<Node<'a>> {
+        self.node().named_child(at)
+    }
+
+    pub fn property(&self, name: &str) -> Option<Node<'a>> {
+        self.node().child_by_field_name(name)
+    }
+
+    pub fn properties(&self, name: &'static str) -> impl Iterator<Item = Node<'a>> {
+        unsafe {
+            self.node().children_by_field_name(name, self.cursor.as_mut().unwrap())
+        }
+    }
+
+    pub fn find<F, T>(&self, name: &str, mut f: F) -> Result<Option<T>>
+    where
+        F: FnMut(Node) -> Result<T>,
+    {
+        self
+            .node()
+            .child_by_field_name(name)
+            .map_or(Ok(None), |node| {
+                let value = f(node)?;
+                Ok(Some(value))
             })
-        }
-        _ => todo!(),
     }
-}
 
-fn specialize_pattern(file: &String, tree: &Tree, cursor: &mut TreeCursor) -> Result<Pat> {
-    let node = cursor.node();
-    match node.kind() {
-        "identifier" => {
-            specialize_name(file, tree, cursor)
-                .map(|name| Pat::new(
-                    Span::default(),
-                    PatKind::Name(name),
-                ))
+    pub fn named_children(&self) -> impl Iterator<Item = Node<'a>> + '_ {
+        unsafe {
+            self.node().named_children(self.cursor.as_mut().unwrap())
         }
-        "constructor_identifier" => {
-            specialize_name(file, tree, cursor)
-                .map(|name| Pat::new(
-                    Span::default(),
-                    PatKind::Name(name),
-                ))
-        }
-        kind => todo!("{}", kind),
     }
-}
 
-fn specialize_expr(file: &String, tree: &Tree, cursor: &mut TreeCursor) -> Result<Expr> {
-    let node = cursor.node();
-    match node.kind() {
-        "call" => {
-            let callee = node
-                .child_by_field_name("callee")
-                .unwrap();
+    pub fn children(&self) -> impl Iterator<Item = Node<'a>> + '_ {
+        let mut cursor = self.get_current_cursor();
 
-            specialize_primary(file, tree, &mut callee.walk())
-        },
-        kind => todo!("{}", kind),
+        cursor.reset(self.node());
+        cursor.goto_first_child();
+        (0..self.node().child_count()).map(move |_| {
+            let result = cursor.node();
+            cursor.goto_next_sibling();
+            result
+        })
     }
-}
 
-fn specialize_name(file: &String, _tree: &Tree, cursor: &mut TreeCursor) -> Result<Name> {
-    let node = cursor.node();
-    match node.kind() {
-        "identifier" => {
-            let name = node.utf8_text(file.as_bytes()).unwrap().to_string();
-
-            Ok(Name::Ident(Ident(Item::new(
-                Span::default(),
-                Tokenized(Token::default(), name),
-            ))))
-        }
-        kind => todo!("{}", kind),
+    pub fn text(&self) -> Result<&'a str> {
+        self.node()
+            .utf8_text(self.file.as_bytes())
+            .map_err(FmtError::Utf8Error)
     }
-}
 
-fn specialize_statements(file: &String, tree: &Tree, cursor: &mut TreeCursor) -> Result<Block> {
-    let node = cursor.node();
-    match node.kind() {
-        "statements" => {
-            let statements = node.named_children(cursor)
-                .map(|node| {
-                    specialize_expr(file, tree, &mut node.walk())
-                })
-                .collect::<Result<ThinVec<_>>>()?;
-
-            Ok(Brace(
-                Token::default(),
-                statements.iter().map(|expr| Stmt {
-                    value: expr.clone(),
-                    semi: None,
-                }).collect(),
-                Token::default(),
-            ))
-        }
-        kind => todo!("{}", kind),
+    pub fn text_of(&self, node: Node<'_>) -> Result<&'a str> {
+        node.utf8_text(self.file.as_bytes())
+            .map_err(FmtError::Utf8Error)
     }
-}
 
-fn specialize_primary(file: &String, tree: &Tree, cursor: &mut TreeCursor) -> Result<Expr> {
-    let node = cursor.node();
-    match node.kind() {
-        "constructor_identifier" => {
-            specialize_name(file, tree, cursor)
-                .map(|name| Expr::new(
-                    Span::default(),
-                    ExprKind::Constructor(Box::new(ConstructorExpr {
-                        name,
-                    })),
-                ))
+    pub fn cursor<'b>(&'b self, node: Node<'b>) -> FmtContext<'b> {
+        // fix this leak
+        let cursor = Box::leak(Box::new(node.walk()));
+        FmtContext {
+            file: self.file,
+            tree: self.tree,
+            cursor,
         }
-        "identifier" => {
-            specialize_name(file, tree, cursor)
-                .map(|name| Expr::new(
-                    Span::default(),
-                    ExprKind::Local(Box::new(LocalExpr {
-                        name,
-                    })),
-                ))
-        }
-        _ => todo!(),
     }
 }
 
@@ -177,7 +156,7 @@ mod tests {
 
     #[test]
     fn it_works() {
-        let expr = run_fmt("bao:pao{a}".into()).unwrap();
+        let expr = run_fmt("Ata (name: U60) : Type { Something }".into()).unwrap();
         println!("{:#?}", expr);
     }
 }
diff --git a/crates/kind-fmt/src/name.rs b/crates/kind-fmt/src/name.rs
new file mode 100644
index 00000000..ec86d10e
--- /dev/null
+++ b/crates/kind-fmt/src/name.rs
@@ -0,0 +1,26 @@
+use kind_syntax::lexemes::{Ident, Item, Name, QualifiedIdent, Span, Token, Tokenized};
+use crate::{Result, FmtContext};
+
+impl<'a> FmtContext<'a> {
+    pub fn name(&mut self) -> Result<Name> {
+        match self.kind() {
+            "identifier" => {
+                let name = self.text()?.to_string();
+
+                Ok(Name::Ident(Ident(Item::new(
+                    Span::default(),
+                    Tokenized(Token::default(), name),
+                ))))
+            }
+            "constructor_identifier" => {
+                let name = self.text()?.to_string();
+
+                Ok(Name::QualifiedIdent(QualifiedIdent(Item::new(
+                    Span::default(),
+                    Tokenized(Token::default(), name),
+                ))))
+            }
+            kind => todo!("{}", kind),
+        }
+    }
+}
\ No newline at end of file
diff --git a/crates/kind-fmt/src/parameter.rs b/crates/kind-fmt/src/parameter.rs
new file mode 100644
index 00000000..f8632adf
--- /dev/null
+++ b/crates/kind-fmt/src/parameter.rs
@@ -0,0 +1,48 @@
+use kind_syntax::concrete::{ParameterBinding, SignatureParameter, TypeBinding};
+use kind_syntax::lexemes::{AngleBracket, Colon, Paren, Token};
+
+use crate::{FmtContext, Result};
+
+impl<'a> FmtContext<'a> {
+    pub fn parameter(&mut self) -> Result<SignatureParameter> {
+        match self.kind() {
+            "parameter" => {
+                let modifier = self.find("modifier", |node| self.text_of(node))?;
+                let signature = match modifier {
+                    Some(x) if x == "+" => SignatureParameter::Include,
+                    Some(x) if x == "-" => SignatureParameter::Exclude,
+                    Some(x) if x == "-+" => SignatureParameter::Both,
+                    Some(x) if x == "+-" => SignatureParameter::Both,
+                    _ => SignatureParameter::Include,
+                };
+
+                let parameter = self.cursor(self.first().unwrap());
+
+                let name = parameter
+                    .find("name", |node| parameter.cursor(node).name())?
+                    .unwrap();
+                let binding_type = parameter.clone().find("type", |node| {
+                    let expr = parameter.cursor(node).expr()?;
+                    Ok(Colon(Token::default(), Box::new(expr)))
+                })?;
+
+                match parameter.kind() {
+                    "explicit_parameter" => Ok(signature(ParameterBinding::Explicit(Paren(
+                        Token::default(),
+                        TypeBinding { name, binding_type },
+                        Token::default(),
+                    )))),
+                    "implicit_parameter" => {
+                        Ok(signature(ParameterBinding::Implicit(AngleBracket(
+                            Token::default(),
+                            TypeBinding { name, binding_type },
+                            Token::default(),
+                        ))))
+                    }
+                    kind => todo!("{}", kind),
+                }
+            }
+            kind => todo!("{}", kind),
+        }
+    }
+}
diff --git a/crates/kind-fmt/src/pattern.rs b/crates/kind-fmt/src/pattern.rs
new file mode 100644
index 00000000..7b5c3392
--- /dev/null
+++ b/crates/kind-fmt/src/pattern.rs
@@ -0,0 +1,15 @@
+use kind_syntax::concrete::{Pat, PatKind};
+use kind_syntax::lexemes::Span;
+use crate::{Result, FmtContext};
+
+impl<'a> FmtContext<'a> {
+    pub fn pattern(&mut self) -> Result<Pat> {
+        match self.kind() {
+            "identifier" | "constructor_identifier" => {
+                let name = self.name()?;
+                Ok(Pat::new(Span::default(), PatKind::Name(name)))
+            }
+            kind => todo!("{}", kind),
+        }
+    }
+}
diff --git a/crates/kind-fmt/src/primary.rs b/crates/kind-fmt/src/primary.rs
new file mode 100644
index 00000000..51633601
--- /dev/null
+++ b/crates/kind-fmt/src/primary.rs
@@ -0,0 +1,19 @@
+use kind_syntax::concrete::Expr;
+use kind_syntax::lexemes::Span;
+use crate::{FmtContext, Result};
+
+impl<'a> FmtContext<'a> {
+    pub fn primary(&mut self) -> Result<Expr> {
+        match self.kind() {
+            "constructor_identifier" => {
+                let name = self.name()?;
+                Ok(Expr::constructor(Span::default(), name))
+            }
+            "identifier" => {
+                let name = self.name()?;
+                Ok(Expr::local(Span::default(), name))
+            }
+            kind => todo!("{}", kind),
+        }
+    }
+}
\ No newline at end of file
diff --git a/crates/kind-fmt/src/statements.rs b/crates/kind-fmt/src/statements.rs
new file mode 100644
index 00000000..c292e01e
--- /dev/null
+++ b/crates/kind-fmt/src/statements.rs
@@ -0,0 +1,32 @@
+use thin_vec::ThinVec;
+
+use kind_syntax::concrete::{Block, Stmt};
+use kind_syntax::lexemes::{Brace, Token};
+
+use crate::{FmtContext, Result};
+
+impl<'a> FmtContext<'a> {
+    pub fn statements(&mut self) -> Result<Block> {
+        match self.kind() {
+            "statements" => {
+                let statements = self
+                    .named_children()
+                    .map(|node| self.cursor(node).expr())
+                    .collect::<Result<ThinVec<_>>>()?;
+
+                Ok(Brace(
+                    Token::default(),
+                    statements
+                        .iter()
+                        .map(|expr| Stmt {
+                            value: expr.clone(),
+                            semi: None,
+                        })
+                        .collect(),
+                    Token::default(),
+                ))
+            }
+            kind => todo!("{}", kind),
+        }
+    }
+}
diff --git a/crates/kind-fmt/src/top_level.rs b/crates/kind-fmt/src/top_level.rs
new file mode 100644
index 00000000..810fa510
--- /dev/null
+++ b/crates/kind-fmt/src/top_level.rs
@@ -0,0 +1,37 @@
+use thin_vec::thin_vec;
+use kind_syntax::concrete::{Signature, TopLevel, TopLevelKind};
+use kind_syntax::lexemes::{Colon, Item, Span, Token};
+use crate::{FmtContext, Result};
+
+impl<'a> FmtContext<'a> {
+    pub fn top_level(&mut self) -> Result<TopLevel> {
+        match self.kind() {
+            "val_declaration" => {
+                let name = self.find("name", |node| self.cursor(node).name())?.unwrap();
+                let value = self.find("value", |node| self.cursor(node).statements())?;
+                let parameters = self
+                    .properties("parameters")
+                    .map(|node| self.cursor(node).parameter())
+                    .collect::<Result<_>>()?;
+                let return_type = self.find("return_type", |node| {
+                    let value = self.cursor(node).expr()?;
+                    Ok(Colon(Token::default(), value))
+                })?;
+
+                Ok(TopLevel {
+                    data: Item::new(
+                        Span::default(),
+                        TopLevelKind::Signature(Signature {
+                            name,
+                            parameters,
+                            return_type,
+                            value,
+                        }),
+                    ),
+                    attributes: thin_vec![],
+                })
+            }
+            kind => todo!("{}", kind),
+        }
+    }
+}
diff --git a/crates/kind-syntax/src/builders.rs b/crates/kind-syntax/src/builders.rs
new file mode 100644
index 00000000..aaece842
--- /dev/null
+++ b/crates/kind-syntax/src/builders.rs
@@ -0,0 +1,32 @@
+use crate::concrete::{ConstructorExpr, Expr, ExprKind, LocalExpr};
+use crate::lexemes::{Name, Span};
+
+impl Expr {
+    pub fn constructor(span: Span, name: Name) -> Self {
+        Expr::new(
+            span,
+            ExprKind::Constructor(Box::new(ConstructorExpr { name })),
+        )
+    }
+
+    pub fn local(span: Span, name: Name) -> Self {
+        Expr::new(span, ExprKind::Local(Box::new(LocalExpr { name })))
+    }
+}
+//
+// macro_rules! impl_expr_kind {
+//     ( $( $name:ident( $( $arg:ident: $ty:ty ),* ) ),* ) => {
+//         impl Expr {
+//             $(pub fn $name($($arg: $ty),* span: Span) -> Self {
+//                 Expr::new(
+//                     span,
+//                     ExprKind::$name(Box::new($name Expr { $($arg),* })))
+//             })*
+//         }
+//     };
+// }
+//
+// impl_expr_kind!(
+//         Local( name: Name, ),
+//         Constructor( name: Name, ),
+// );
diff --git a/crates/kind-syntax/src/concrete.rs b/crates/kind-syntax/src/concrete.rs
index ebf9820a..046c2d2a 100644
--- a/crates/kind-syntax/src/concrete.rs
+++ b/crates/kind-syntax/src/concrete.rs
@@ -41,22 +41,22 @@ pub type Attribute = Item<AttributeKind>;
 /// A type binding is a type annotation for a variable.
 #[derive(Debug, Clone, PartialEq)]
 pub struct TypeBinding {
-    pub name: Ident,
-    pub typ: Colon<Box<Expr>>,
+    pub name: Name,
+    pub binding_type: Option<Colon<Box<Expr>>>,
 }
 
 #[derive(Debug, Clone, PartialEq)]
-pub enum ArgumentBinding {
-    Implicit(AngleBracket<Param>),
-    Explicit(Paren<Param>),
+pub enum ParameterBinding {
+    Implicit(AngleBracket<TypeBinding>),
+    Explicit(Paren<TypeBinding>),
 }
 
 /// An argument of a type signature.
 #[derive(Debug, Clone, PartialEq)]
-pub struct Argument {
-    pub minus: Option<lexemes::Minus>,
-    pub plus: Option<lexemes::Plus>,
-    pub binding: ArgumentBinding,
+pub enum SignatureParameter {
+    Exclude(ParameterBinding),
+    Include(ParameterBinding),
+    Both(ParameterBinding),
 }
 
 /// A local expression is a reference atom to a local declaration.
@@ -79,9 +79,8 @@ pub struct ConstructorExpr {
 /// (x : Int)
 /// // or
 /// x
-/// ```
 #[derive(Debug, Clone, PartialEq)]
-pub enum Param {
+pub enum PiParameter {
     Named(Paren<TypeBinding>),
     Expr(Box<Expr>),
 }
@@ -90,7 +89,7 @@ pub enum Param {
 #[derive(Debug, Clone, PartialEq)]
 pub struct PiExpr {
     pub r#tilde: lexemes::Tilde,
-    pub param: Param,
+    pub param: PiParameter,
     pub r#arrow: lexemes::RightArrow,
     pub body: Box<Expr>,
 }
@@ -109,7 +108,7 @@ pub struct SigmaExpr {
 #[derive(Debug, Clone, PartialEq)]
 pub struct LambdaExpr {
     pub r#tilde: Option<lexemes::Tilde>,
-    pub param: Param,
+    pub param: PiParameter,
     pub r#arrow: lexemes::FatArrow,
     pub body: Box<Expr>,
 }
@@ -309,7 +308,7 @@ pub struct CaseNode {
 pub struct MatchExpr {
     pub r#match: lexemes::Match,
     pub typ: Option<Ident>,
-    pub with: Option<(lexemes::With, ThinVec<Param>)>,
+    pub with: Option<(lexemes::With, ThinVec<PiParameter>)>,
     pub scrutinee: Box<Expr>,
     pub cases: Brace<ThinVec<CaseNode>>,
     pub motive: Option<Colon<Box<Expr>>>,
@@ -387,7 +386,7 @@ pub type Expr = Item<ExprKind>;
 #[derive(Debug, Clone, PartialEq)]
 pub struct ConstructorPat {
     pub name: QualifiedIdent,
-    pub args: ThinVec<Argument>,
+    pub args: ThinVec<SignatureParameter>,
 }
 
 /// A pattern is part of a rule. It is a structure that matches an expression.
@@ -411,7 +410,7 @@ pub type Pat = Item<PatKind>;
 #[derive(Debug, Clone, PartialEq)]
 pub struct Signature {
     pub name: Name,
-    pub arguments: ThinVec<Argument>,
+    pub parameters: ThinVec<SignatureParameter>,
     pub return_type: Option<Colon<Expr>>,
     pub value: Option<Block>,
 }
@@ -440,7 +439,7 @@ pub struct Rule {
 #[derive(Debug, Clone, PartialEq)]
 pub struct Function {
     pub name: Ident,
-    pub arguments: ThinVec<Argument>,
+    pub arguments: ThinVec<SignatureParameter>,
     pub return_typ: Option<Colon<Expr>>,
     pub value: Brace<Expr>,
 }
@@ -468,7 +467,7 @@ pub struct Command {
 #[derive(Debug, Clone, PartialEq)]
 pub struct Constructor {
     pub name: Ident,
-    pub arguments: ThinVec<Argument>,
+    pub arguments: ThinVec<SignatureParameter>,
     pub typ: Option<Colon<ThinVec<Expr>>>,
 }
 
@@ -478,8 +477,8 @@ pub struct Constructor {
 pub struct TypeDef {
     pub name: QualifiedIdent,
     pub constructors: ThinVec<Constructor>,
-    pub params: ThinVec<Argument>,
-    pub indices: ThinVec<Argument>,
+    pub params: ThinVec<SignatureParameter>,
+    pub indices: ThinVec<SignatureParameter>,
 }
 
 /// A record definition is a top-level structure that defines a type with
@@ -488,8 +487,8 @@ pub struct TypeDef {
 pub struct RecordDef {
     pub name: QualifiedIdent,
     pub fields: ThinVec<TypeBinding>,
-    pub params: ThinVec<Argument>,
-    pub indices: ThinVec<Argument>,
+    pub params: ThinVec<SignatureParameter>,
+    pub indices: ThinVec<SignatureParameter>,
 }
 
 /// A top-level item is a item that is on the outermost level of a
diff --git a/crates/kind-syntax/src/lib.rs b/crates/kind-syntax/src/lib.rs
index 9a1646ab..86e7bc23 100644
--- a/crates/kind-syntax/src/lib.rs
+++ b/crates/kind-syntax/src/lib.rs
@@ -4,3 +4,4 @@
 pub mod concrete;
 pub mod core;
 pub mod lexemes;
+pub mod builders;