diff --git a/crates/codegen/src/top_level.rs b/crates/codegen/src/top_level.rs
index bbe1490..e4ed540 100644
--- a/crates/codegen/src/top_level.rs
+++ b/crates/codegen/src/top_level.rs
@@ -24,7 +24,21 @@ impl GetRust for GenericsDecl {
 impl GetRust for GenericDecl {
     fn get_rust(&self) -> String {
         match self {
-            GenericDecl::Lifetime(name) => format!("'{}", name.get_rust()),
+            GenericDecl::Lifetime(name, requirements) => {
+                format!("'{}", name.get_rust())
+                    + &(if requirements.len() != 0 {
+                        format!(
+                            ": {}",
+                            requirements
+                                .into_iter()
+                                .map(GetRust::get_rust)
+                                .collect::<Vec<_>>()
+                                .join("+")
+                        )
+                    } else {
+                        String::new()
+                    })
+            }
             GenericDecl::Type(name, requirements) => {
                 name.get_rust()
                     + &(if requirements.len() != 0 {
@@ -32,7 +46,7 @@ impl GetRust for GenericDecl {
                             ": {}",
                             requirements
                                 .into_iter()
-                                .map(TypeExpr::get_rust)
+                                .map(GetRust::get_rust)
                                 .collect::<Vec<_>>()
                                 .join("+")
                         )
diff --git a/crates/parser/src/ast/mod.rs b/crates/parser/src/ast/mod.rs
index 4731ba0..5b52ebb 100644
--- a/crates/parser/src/ast/mod.rs
+++ b/crates/parser/src/ast/mod.rs
@@ -60,7 +60,7 @@ pub struct Spanned<T> {
 impl From<GenericDecl> for Generic {
     fn from(value: GenericDecl) -> Self {
         match value {
-            GenericDecl::Lifetime(life) => Generic::Lifetime(life),
+            GenericDecl::Lifetime(life, _) => Generic::Lifetime(life),
             GenericDecl::Type(ty, _) => Generic::Type(TypeExpr::Path(Path(vec![ty]), None)),
         }
     }
diff --git a/crates/parser/src/ast/top_level.rs b/crates/parser/src/ast/top_level.rs
index fd8427e..20ceba9 100644
--- a/crates/parser/src/ast/top_level.rs
+++ b/crates/parser/src/ast/top_level.rs
@@ -82,8 +82,8 @@ pub struct GenericsDecl(pub Vec<GenericDecl>);
 
 #[derive(Debug, Clone, Serialize)]
 pub enum GenericDecl {
-    Lifetime(Identifier),
-    Type(Identifier, Vec<TypeExpr>),
+    Lifetime(Identifier, Vec<Generic>),
+    Type(Identifier, Vec<Generic>),
 }
 
 #[derive(Debug, Clone, Serialize)]
diff --git a/crates/parser/src/grammar.pest b/crates/parser/src/grammar.pest
index a51c7e2..391ef69 100644
--- a/crates/parser/src/grammar.pest
+++ b/crates/parser/src/grammar.pest
@@ -90,7 +90,7 @@ mutable    = { "mut" }
 // ======================================================
 // GENERICS
 // ======================================================
-generic_decl  = { lifetime | (identifier ~ (":" ~ generic ~ ("+" ~ generic)*)?) }
+generic_decl  = { (lifetime | identifier) ~ (":" ~ generic ~ ("+" ~ generic)*)? }
 generics_decl = { "<" ~ (generic_decl ~ ("," ~ generic_decl)*)? ~ ">" }
 
 generic  = { lifetime | type_expr }
@@ -125,9 +125,9 @@ fn_kind_mut     = { "FnMut" }
 fn_kind = _{
     fn_kind_fn
   | fn_kind_unsafe
-  | fn_kind_closure
   | fn_kind_once
   | fn_kind_mut
+  | fn_kind_closure
 }
 
 fn_type = {
diff --git a/crates/parser/src/parser/common/types.rs b/crates/parser/src/parser/common/types.rs
index 341733e..ddb4bdc 100644
--- a/crates/parser/src/parser/common/types.rs
+++ b/crates/parser/src/parser/common/types.rs
@@ -131,6 +131,7 @@ impl<'a> TryFrom<pest::iterators::Pair<'a, Rule>> for GenericDecl {
             if let Some(pair) = consume_rule(&mut inner, Rule::lifetime) {
                 Ok(GenericDecl::Lifetime(
                     pair.into_inner().next().unwrap().try_into()?,
+                    collect_recovered(inner)?,
                 ))
             } else {
                 Ok(GenericDecl::Type(