diff --git a/src/frontend.rs b/src/frontend.rs
index 2346c2e..a1995f0 100644
--- a/src/frontend.rs
+++ b/src/frontend.rs
@@ -6,7 +6,7 @@ use crate::parser::expression::Expression;
 use crate::rtlil;
 use crate::rtlil::RtlilWrite;
 pub use callable::Callable;
-pub use types::{Type, TypeStruct};
+pub use types::{make_primitives, Type, TypeStruct};
 
 mod callable;
 pub mod typed_ir;
@@ -64,7 +64,7 @@ struct Context<'ctx> {
     /// map callable name to callable
     callables: BTreeMap<String, Callable<'ctx>>,
     /// types
-    types: Vec<TypeStruct<'ctx>>,
+    types: BTreeMap<String, TypeStruct<'ctx>>,
     /// map signal name to Signal
     signals: BTreeMap<String, Signal<'ctx>>,
 }
@@ -79,6 +79,12 @@ impl<'ctx> Context<'ctx> {
             CompileError::new(CompileErrorKind::UndefinedReference(signame.to_owned()))
         })
     }
+
+    fn try_get_type(&self, typename: &str) -> Result<Type, CompileError> {
+        self.types.get(typename).ok_or_else(|| {
+            CompileError::new(CompileErrorKind::UndefinedReference(typename.to_owned()))
+        })
+    }
 }
 
 fn lower_process_statement(
@@ -285,6 +291,8 @@ fn lower_comb(
 ) -> Result<(), CompileError> {
     for (num, port) in pa_comb.ports.iter().enumerate() {
         let port_id = make_pubid(port.net.name.fragment());
+        let port_tyname = &port.net.typ;
+        ctx.try_get_type(port_tyname.name.fragment())?;
         module.add_wire(rtlil::Wire::new(
             port_id.clone(),
             TODO_WIDTH,
@@ -304,7 +312,7 @@ fn lower_comb(
     module.add_wire(rtlil::Wire::new(
         ret_id.clone(),
         TODO_WIDTH,
-        Some(rtlil::PortOption::Input(99)),
+        Some(rtlil::PortOption::Output(99)),
     ));
     let out_sig = lower_expression(ctx, module, &pa_comb.expr)?;
     module.add_connection(&rtlil::SigSpec::Wire(ret_id), &out_sig);
@@ -320,7 +328,7 @@ pub fn lower_module(pa_module: parser::Module) -> Result<String, CompileError> {
             .map(|clb| (clb.name().to_owned(), clb))
             .collect(),
         signals: BTreeMap::new(),
-        types: vec![],
+        types: make_primitives().into_iter().collect(),
     };
 
     writer.write_line("autoidx 1");
diff --git a/src/frontend/types.rs b/src/frontend/types.rs
index 7ef306c..a217325 100644
--- a/src/frontend/types.rs
+++ b/src/frontend/types.rs
@@ -7,7 +7,7 @@ pub struct TypeStruct<'ty> {
     kind: TypeKind<'ty>,
 }
 
-pub enum TypeKind<'ty> {
+enum TypeKind<'ty> {
     /// Elaboration-time types
     ElabType(ElabKind),
     /// Signal/Wire of generic width
@@ -58,7 +58,7 @@ impl<'ty> TypeStruct<'ty> {
     /// a logic signal with known width
     pub fn logic_width(width: u32) -> Self {
         Self {
-            kind: TypeKind::Logic(ElabData::u32(width)),
+            kind: TypeKind::Logic(ElabData::from_u32(width)),
         }
     }
 
@@ -68,12 +68,32 @@ impl<'ty> TypeStruct<'ty> {
             kind: TypeKind::ElabType(ElabKind::Num),
         }
     }
+
+    pub fn bit_width(&self) -> Option<u32> {
+        match &self.kind {
+            // elab types are not representable in hardware
+            TypeKind::ElabType(_) => None,
+            TypeKind::Logic(data) => data.try_u32(),
+            TypeKind::UInt(_) => todo!(),
+            // callables are not representable in hardware
+            TypeKind::Callable => None,
+        }
+    }
+
+    pub fn genparam_count(&self) -> u32 {
+        match self.kind {
+            TypeKind::ElabType(_) => todo!(),
+            TypeKind::Logic(_) => 1,
+            TypeKind::UInt(_) => 1,
+            TypeKind::Callable => todo!(),
+        }
+    }
 }
 
 /// Helper functions to create primitive elaboration values
 impl<'ty> ElabData<'ty> {
     /// an integer
-    pub fn u32(val: u32) -> Self {
+    pub fn from_u32(val: u32) -> Self {
         Self {
             typ: &TypeStruct {
                 kind: TypeKind::ElabType(ElabKind::Num),
@@ -81,4 +101,17 @@ impl<'ty> ElabData<'ty> {
             value: ElabValue::Concrete(ElabValueData::U32(val)),
         }
     }
+
+    /// return Some(u32) if this is a number
+    pub fn try_u32(&self) -> Option<u32> {
+        // TODO: assert this is actually a number
+        match self.value {
+            ElabValue::Infer => None,
+            ElabValue::Concrete(_) => todo!(),
+        }
+    }
+}
+
+pub fn make_primitives() -> Vec<(String, TypeStruct<'static>)> {
+    vec![("Logic".to_string(), TypeStruct::logic_infer())]
 }
diff --git a/src/parser/declaration.rs b/src/parser/declaration.rs
index 6426fd3..dca1de8 100644
--- a/src/parser/declaration.rs
+++ b/src/parser/declaration.rs
@@ -24,8 +24,8 @@ pub fn typename(input: TokenSpan) -> IResult<TokenSpan, TypeName> {
 
 #[derive(Debug)]
 pub struct TypeName<'a> {
-    name: Span<'a>,
-    generics: (),
+    pub name: Span<'a>,
+    pub generics: (),
 }
 
 #[derive(Debug)]
diff --git a/src/parser/expression.rs b/src/parser/expression.rs
index c7320e1..77d48b6 100644
--- a/src/parser/expression.rs
+++ b/src/parser/expression.rs
@@ -80,8 +80,8 @@ fn unary(input: TokenSpan) -> IResult<TokenSpan, Expression> {
 fn bitop_kind(input: TokenSpan) -> IResult<TokenSpan, BinOpKind> {
     alt((
         map(token(tk::BitXor), |_| BinOpKind::Xor),
-        map(token(tk::BitOr), |_| BinOpKind::Xor),
-        map(token(tk::BitAnd), |_| BinOpKind::Xor),
+        map(token(tk::BitOr), |_| BinOpKind::Or),
+        map(token(tk::BitAnd), |_| BinOpKind::And),
     ))(input)
 }