diff --git a/src/main.rs b/src/main.rs
index 34eedba..6abf52e 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -6,9 +6,18 @@ use {
     laddertypes::{
         dict::TypeDict, parser::ParseLadderType, subtype_unify, unparser::UnparseLadderType, BimapTypeDict, Morphism, MorphismType
     },
-    std::sync::{Arc, RwLock}
+    std::{any::Any, sync::{Arc, RwLock}}
 };
 
+/*
+*/
+pub fn get_c_repr_kind(kind: String) -> Option<String> {
+    match kind.as_str() {
+        "ℤ" => Some("uint64_t".into()),
+        _ => None
+    }
+}
+
 /* for a given ladder type `t`, get the corresponding C type
  */
 pub fn get_c_repr_type(dict: &mut impl TypeDict, t: laddertypes::TypeTerm, skip_pointer: bool) -> Option<String> {
@@ -66,16 +75,38 @@ pub fn get_c_repr_type(dict: &mut impl TypeDict, t: laddertypes::TypeTerm, skip_
 #[derive(Clone, Debug)]
 struct LdmcPrimCMorphism {
     symbol: String,
-    type_args: Vec<(String, String)>,
+    type_args: Vec<(laddertypes::TypeID, String)>,
     src_type: laddertypes::TypeTerm,
     dst_type: laddertypes::TypeTerm,
     locations: Vec<String>
 }
 
 impl LdmcPrimCMorphism {
-    pub fn expected_c_type_signature(&self, dict: &mut impl TypeDict) -> String {
+    pub fn instantiated_symbol_name(&self, dict: &mut impl TypeDict,
+        σ: &std::collections::HashMap<laddertypes::TypeID, laddertypes::TypeTerm>) -> String {
+        let mut s = self.symbol.clone();
+        for (k_id,v) in self.type_args.iter() {
+            if let Some(val_trm) = σ.get(k_id) {
+                if let laddertypes::TypeID::Var(var_id) = k_id {
+                    let name = dict.get_varname(*var_id).unwrap();
+                    let val_str = dict.unparse(val_trm);
+                    s.push_str(&format!("_{}_{}", name, val_str));
+                }
+            } else {
+                if let laddertypes::TypeID::Var(var_id) = k_id {
+                    let k = dict.get_varname(*var_id).unwrap();
+                    s.push_str(&format!("_{:?}_MISSING", k));
+                    eprintln!("INCOMPLETE MORPHISM INSTANTIATION, missing {} ({})", k, var_id);
+                }
+            }
+        }
+        s
+    }
+
+    pub fn expected_c_type_signature(&self, dict: &mut impl TypeDict,
+        σ: &std::collections::HashMap<laddertypes::TypeID, laddertypes::TypeTerm>) -> String {
         format!("int {} ({} const * restrict src, {} * restrict dst);",
-            self.symbol,
+            self.instantiated_symbol_name(dict, σ),
             get_c_repr_type(dict, self.src_type.clone(), true).expect("cant get c-repr type for src type"),
             get_c_repr_type(dict, self.dst_type.clone(), true).expect("cant get c-repr type for dst type"))
     }
@@ -95,7 +126,7 @@ enum LdmcMorphism {
 }
 
 impl LdmcMorphism {
-    pub fn generate_call(&self, dict: &mut impl TypeDict, i: u64) {
+    pub fn generate_call(&self, dict: &mut impl TypeDict, σ: &std::collections::HashMap<laddertypes::TypeID, laddertypes::TypeTerm>, i: u64) {
         match self {
             LdmcMorphism::Primitive(prim_morph) => {
                 let src_c_type = get_c_repr_type(dict, prim_morph.src_type.clone(), true).expect("cant get c-repr type for src type");
@@ -103,6 +134,7 @@ impl LdmcMorphism {
 
                 let src_buf = if i%2 == 0 { "bufA" } else { "bufB" };
                 let dst_buf = if i%2 == 0 { "bufB" } else { "bufA" };
+
                 println!(r#"
     {}
             {} const * restrict src = (void*) {};
@@ -112,7 +144,7 @@ impl LdmcMorphism {
                     '{',
                     src_c_type, src_buf,
                     dst_c_type, dst_buf,
-                    prim_morph.symbol,
+                    prim_morph.instantiated_symbol_name(dict, σ),
                     '}');
             }
             LdmcMorphism::LengthPrefixMap { length_prefix_type, item_morph } => {
@@ -146,7 +178,7 @@ impl LdmcMorphism {
                     src_c_type, src_buf,
                     dst_c_type, dst_buf,
                     map_fn,
-                    item_morph.symbol,
+                    item_morph.instantiated_symbol_name(dict, σ),
                     '}');
             }
             LdmcMorphism::ValueDelimMap { delim, item_morph } => {
@@ -164,7 +196,7 @@ impl LdmcMorphism {
             '{',
                     src_c_type, src_buf,
                     dst_c_type, dst_buf,
-                    item_morph.symbol,
+                    item_morph.instantiated_symbol_name(dict, σ),
                     '}');
             }
         }
@@ -253,8 +285,11 @@ fn parser(
         move |(((symbol, type_args), ((src_type, _), (dst_type, _))), locations)| {
             let mut type_dict = type_dict.write().unwrap();
             let type_args : Vec<_> = type_args.into_iter().map(|(v,k)| (v,k.into_iter().collect())).collect();
-            for (var, kind) in type_args.iter() {
-                type_dict.add_varname(var.clone());
+            let mut ty_args = Vec::new();
+            for (var, kind) in type_args.into_iter() {
+                let var_id = type_dict.add_varname(var.clone());
+                eprintln!("parser: add varname {} -> {:?}", var, type_dict.get_typeid(&var));
+                ty_args.push((var_id, kind));
             }
 
             let mut src_type = type_dict.parse(&src_type.iter().collect::<String>()).expect("couldnt parse src type");
@@ -262,7 +297,7 @@ fn parser(
 
             LdmcPrimCMorphism {
                 symbol,
-                type_args,
+                type_args: ty_args,
                 src_type,
                 dst_type,
                 locations: locations.into_iter().map(|l| l.into_iter().collect()).collect()
@@ -314,8 +349,8 @@ fn main() {
     let path = morphism_base.find_morphism_path(MorphismType {
         src_type: type_dict.parse( src_type_arg.as_str() ).expect(""),
         dst_type: type_dict.parse( dst_type_arg.as_str() ).expect(""),
-    },
-    &mut *type_dict.write().unwrap()
+    }//,
+   // &mut *type_dict.write().unwrap()
     );
 
     match path {
@@ -340,7 +375,7 @@ int main() {{
     ...with
     morph {}
      ---> {},
-    subst σ = {{ {:?} }},
+    subst σ = {:?},
     halo  Ψ = {}
     */"#,
                     type_dict.unparse(&morph_inst.get_type().dst_type.param_normalize().decurry()),
@@ -349,7 +384,7 @@ int main() {{
                     morph_inst.σ,
                     type_dict.unparse(&morph_inst.halo),
                 );
-                morph_inst.m.generate_call(&mut type_dict, i);
+                morph_inst.m.generate_call(&mut type_dict, &morph_inst.σ, i);
                 i += 1;
             }