diff --git a/implementations/rust/preserves-schema/src/bin/preserves-schema-rs.rs b/implementations/rust/preserves-schema/src/bin/preserves-schema-rs.rs
index f2862e7..8d7d9fd 100644
--- a/implementations/rust/preserves-schema/src/bin/preserves-schema-rs.rs
+++ b/implementations/rust/preserves-schema/src/bin/preserves-schema-rs.rs
@@ -35,11 +35,7 @@ fn main() -> Result<(), Error> {
             (pieces[0], pieces[1])
         };
         let modulepath: Vec<String> = modulepath_str.split('.').map(str::to_owned).collect();
-        config.add_external_module(ExternalModule {
-            path: modulepath,
-            rust_namespace: target.to_owned(),
-            rust_language_type: None,
-        });
+        config.add_external_module(ExternalModule::new(modulepath, target));
     }
     if let Some(c) = args.support_crate {
         config.support_crate = c;
diff --git a/implementations/rust/preserves-schema/src/compiler/context.rs b/implementations/rust/preserves-schema/src/compiler/context.rs
index bdf84f7..c4c191b 100644
--- a/implementations/rust/preserves-schema/src/compiler/context.rs
+++ b/implementations/rust/preserves-schema/src/compiler/context.rs
@@ -78,6 +78,10 @@ impl<'b> BundleContext<'b> {
         }
     }
 
+    pub fn any_type(&self) -> &'static str {
+        "_Value"
+    }
+
     pub fn type_for_name(&self, r: &Ref) -> Option<&types::TDefinition> {
         if r.module.0.is_empty() {
             panic!("BundleContext::type_for_name with module-relative ref {:?}", r);
@@ -99,7 +103,9 @@ impl<'b> BundleContext<'b> {
             _ => prefix
         };
         let next_id = next_id.to_case(Case::UpperSnake);
-        format!("&_ctxt.into().{}", self.literals.entry(v.clone()).or_insert(next_id))
+        format!("&<_L as Into<&'a {}>>::into(_ctxt).{}",
+                self.language_type(),
+                self.literals.entry(v.clone()).or_insert(next_id))
     }
 
     pub fn generate_module<F: FnOnce(&mut ModuleContext)>(
@@ -118,6 +124,16 @@ impl<'b> BundleContext<'b> {
     pub fn language_struct_name(&self) -> &'static str {
         "Language"
     }
+
+    pub fn language_type_base(&self) -> String {
+        format!("{}::{}",
+                self.config.fully_qualified_module_prefix.clone(),
+                self.language_struct_name())
+    }
+
+    pub fn language_type(&self) -> String {
+        format!("{}<{}>", self.language_type_base(), self.any_type())
+    }
 }
 
 impl<'m, 'b> ModuleContext<'m, 'b> {
@@ -137,6 +153,10 @@ impl<'m, 'b> ModuleContext<'m, 'b> {
         }
     }
 
+    pub fn any_type(&self) -> &'static str {
+        self.bundle.any_type()
+    }
+
     pub fn reset_mode(&mut self) {
         self.mode = ModuleContextMode::TargetToplevel;
     }
@@ -178,21 +198,20 @@ impl<'m, 'b> ModuleContext<'m, 'b> {
         }
     }
 
-    pub fn any_type(&self) -> &'static str {
-        "_Value"
-    }
-
     pub fn ref_has_embedded(&self, r: &Ref) -> bool {
         let r = r.qualify(&self.module_path);
         self.bundle.type_for_name(&r).map(|ty| ty.has_embedded(self.bundle)).unwrap_or(false)
         // ^ TODO: should the "false" be configurable?
     }
 
-    pub fn language_type(&self) -> Item {
-        item(seq![self.bundle.config.fully_qualified_module_prefix.clone(),
-                  "::",
-                  self.bundle.language_struct_name(),
-                  anglebrackets![self.any_type()]])
+    pub fn parse_unparse_generic_decls(&self, ty: &types::TDefinition) -> Item {
+        let mut lts = ty.language_types(self.bundle);
+        lts.insert(self.bundle.language_type());
+        item(anglebrackets![
+            "'a",
+            seq!["_L: Copy",
+                 seq(lts.into_iter().map(|t| item(seq![" + Into<&'a ", t, ">"])).collect())],
+            seq![self.any_type(), ": preserves::value::NestedValue + 'a"]])
     }
 
     pub fn extract(&mut self) -> Vec<Item> {
diff --git a/implementations/rust/preserves-schema/src/compiler/mod.rs b/implementations/rust/preserves-schema/src/compiler/mod.rs
index 1d4807c..27ad08f 100644
--- a/implementations/rust/preserves-schema/src/compiler/mod.rs
+++ b/implementations/rust/preserves-schema/src/compiler/mod.rs
@@ -17,6 +17,7 @@ use glob::glob;
 use preserves::value::BinarySource;
 use preserves::value::IOBinarySource;
 use preserves::value::Map;
+use preserves::value::Set;
 use preserves::value::Reader;
 
 use std::fs::DirBuilder;
@@ -39,11 +40,58 @@ pub trait Plugin: std::fmt::Debug {
     );
 }
 
+pub struct LanguageTypes {
+    pub fallback: Option<Box<dyn Fn(&str) -> Set<String>>>,
+    pub definitions: Map<String, Box<dyn Fn(&str) -> Set<String>>>,
+}
+
+impl std::fmt::Debug for LanguageTypes {
+    fn fmt(&self, f: &mut std::fmt::Formatter) -> Result<(), std::fmt::Error> {
+        f.debug_struct("LanguageTypes")
+            .field("fallback", &self.fallback.as_ref().map(|f| f("_")))
+            .field("definitions", &self.definitions.iter().map(
+                |(k, f)| (k.clone(), f("_"))).collect::<Map<String, Set<String>>>())
+            .finish()
+    }
+}
+
 #[derive(Debug)]
 pub struct ExternalModule {
     pub path: ModulePath,
     pub rust_namespace: String,
-    pub rust_language_type: Option<String>,
+    pub rust_language_types: LanguageTypes,
+}
+
+impl ExternalModule {
+    pub fn new(path: ModulePath, rust_namespace: &str) -> Self {
+        ExternalModule {
+            path,
+            rust_namespace: rust_namespace.to_owned(),
+            rust_language_types: LanguageTypes {
+                fallback: None,
+                definitions: Map::new(),
+            },
+        }
+    }
+
+    pub fn set_fallback_language_types<F: 'static + Fn(&str) -> Set<String>>(
+        mut self,
+        f: F,
+    ) -> Self {
+        self.rust_language_types.fallback = Some(Box::new(f));
+        self
+    }
+
+    pub fn set_definition_language_types<F: 'static + Fn(&str) -> Set<String>>(
+        mut self,
+        d: &str,
+        f: F,
+    ) -> Self {
+        if self.rust_language_types.definitions.insert(d.to_owned(), Box::new(f)).is_some() {
+            panic!("Duplicate language types definition installed: {:?} {:?}", &self.path, d);
+        }
+        self
+    }
 }
 
 #[derive(Debug)]
diff --git a/implementations/rust/preserves-schema/src/compiler/parsers.rs b/implementations/rust/preserves-schema/src/compiler/parsers.rs
index 3d6113b..5c9419d 100644
--- a/implementations/rust/preserves-schema/src/compiler/parsers.rs
+++ b/implementations/rust/preserves-schema/src/compiler/parsers.rs
@@ -45,10 +45,7 @@ pub fn gen_definition_parser(m: &mut ModuleContext, n: &str, d: &Definition) {
                                 construct(&ctxt, ctorname, false, &pattern_type(pat), dest, &mut body);
 
                                 item(seq!["fn ", fname.clone(),
-                                          anglebrackets![
-                                              "'a",
-                                              seq!["_L: Copy + Into<&'a ", ctxt.m.language_type(), ">"],
-                                              seq![ctxt.m.any_type(), ": preserves::value::NestedValue + 'a"]],
+                                          ctxt.m.parse_unparse_generic_decls(&ty),
                                           "(_ctxt: _L, value: &", ctxt.m.any_type(), ") -> ",
                                           "std::result::Result<",
                                           names::render_constructor(n), ty.generic_arg(ctxt.m),
@@ -75,10 +72,7 @@ pub fn gen_definition_parser(m: &mut ModuleContext, n: &str, d: &Definition) {
             }
 
             item(seq!["impl",
-                      anglebrackets![
-                          "'a",
-                          seq!["_L: Copy + Into<&'a ", ctxt.m.language_type(), ">"],
-                          seq![ctxt.m.any_type(), ": preserves::value::NestedValue + 'a"]],
+                      ctxt.m.parse_unparse_generic_decls(&ty),
                       " _support::Parse", anglebrackets!["_L", ctxt.m.any_type()], " for ",
                       names::render_constructor(n), ty.generic_arg(ctxt.m), " ",
                       codeblock![
diff --git a/implementations/rust/preserves-schema/src/compiler/types.rs b/implementations/rust/preserves-schema/src/compiler/types.rs
index 5fcc89d..63d30df 100644
--- a/implementations/rust/preserves-schema/src/compiler/types.rs
+++ b/implementations/rust/preserves-schema/src/compiler/types.rs
@@ -191,6 +191,37 @@ pub fn field_type(p: &SimplePattern) -> TField {
     }
 }
 
+struct WalkState<'a, 'b> {
+    ctxt: &'a BundleContext<'b>,
+    current_module_path: ModulePath,
+    seen: Set<Ref>,
+}
+
+impl<'a, 'b> WalkState<'a, 'b> {
+    fn cycle_check<R, Ks: FnOnce(&mut Self, Option<&TDefinition>) -> R, Kf: FnOnce() -> R>(
+        &mut self,
+        r: &Ref,
+        ks: Ks,
+        kf: Kf,
+    ) -> R {
+        let r = r.qualify(&self.current_module_path);
+        if self.seen.contains(&r) {
+            kf()
+        } else {
+            self.seen.insert(r.clone());
+            match self.ctxt.type_for_name(&r) {
+                Some(ty) => {
+                    let saved = std::mem::replace(&mut self.current_module_path, ty.self_ref.module.clone());
+                    let result = ks(self, Some(ty));
+                    self.current_module_path = saved;
+                    result
+                },
+                None => ks(self, None),
+            }
+        }
+    }
+}
+
 impl TField {
     fn render(&self, ctxt: &ModuleContext, box_needed: bool) -> impl Emittable {
         match self {
@@ -213,28 +244,39 @@ impl TField {
         }
     }
 
-    pub fn has_embedded(&self, default_module_path: &ModulePath, ctxt: &BundleContext, seen: &mut Set<Ref>) -> bool {
+    fn language_types(&self, s: &mut WalkState, ts: &mut Set<String>) {
         match self {
-            TField::Unit => false,
-            TField::Any => true, // at least potentially true
-            TField::Embedded => true,
-            TField::Array(f) => f.has_embedded(default_module_path, ctxt, seen),
-            TField::Set(f) => f.has_embedded(default_module_path, ctxt, seen),
-            TField::Map(k, v) =>
-                k.has_embedded(default_module_path, ctxt, seen) ||
-                v.has_embedded(default_module_path, ctxt, seen),
-            TField::Ref(r) => {
-                let r = r.qualify(default_module_path);
-                if seen.contains(&r) {
-                    false
-                } else {
-                    seen.insert(r.clone());
-                    ctxt.type_for_name(&r).map(|ty| ty._has_embedded(ctxt, seen)).unwrap_or(false)
-                    // ^ TODO: should the "false" be configurable?
-                    // cf. ModuleContext::ref_has_embedded.
-                }
+            TField::Unit | TField::Any | TField::Embedded | TField::Base(_) => (),
+            TField::Array(f) => f.language_types(s, ts),
+            TField::Set(f) => f.language_types(s, ts),
+            TField::Map(k, v) => {
+                k.language_types(s, ts);
+                v.language_types(s, ts);
             }
-            TField::Base(_) => false,
+            TField::Ref(r) =>
+                s.cycle_check(r, |s,t| match t {
+                    Some(ty) => ty._language_types(s, ts),
+                    None => {
+                        let xmts = &s.ctxt.config.external_modules.get(&r.module.0).unwrap()
+                            .rust_language_types;
+                        if let Some(f) = xmts.definitions.get(&r.name).or(xmts.fallback.as_ref()) {
+                            ts.extend(f(s.ctxt.any_type()));
+                        }
+                    }
+                }, || ()),
+        }
+    }
+
+    fn has_embedded(&self, s: &mut WalkState) -> bool {
+        match self {
+            TField::Unit | TField::Base(_) => false,
+            TField::Any | TField::Embedded => true, // at least potentially true
+            TField::Array(f) => f.has_embedded(s),
+            TField::Set(f) => f.has_embedded(s),
+            TField::Map(k, v) => k.has_embedded(s) || v.has_embedded(s),
+            TField::Ref(r) =>
+                // v TODO: should the "false" be configurable? cf. ModuleContext::ref_has_embedded.
+                s.cycle_check(r, |s,t| t.map(|t| t._has_embedded(s)).unwrap_or(false), || false),
         }
     }
 }
@@ -254,12 +296,17 @@ impl TSimple {
              }]
     }
 
-    pub fn has_embedded(&self, default_module_path: &ModulePath, ctxt: &BundleContext, seen: &mut Set<Ref>) -> bool {
+    fn language_types(&self, s: &mut WalkState, ts: &mut Set<String>) {
         match self {
-            TSimple::Field(f) =>
-                f.has_embedded(default_module_path, ctxt, seen),
-            TSimple::Record(TRecord(fs)) =>
-                fs.iter().any(|(_k, v)| v.has_embedded(default_module_path, ctxt, seen)),
+            TSimple::Field(f) => f.language_types(s, ts),
+            TSimple::Record(TRecord(fs)) => fs.iter().for_each(|(_k, v)| v.language_types(s, ts)),
+        }
+    }
+
+    fn has_embedded(&self, s: &mut WalkState) -> bool {
+        match self {
+            TSimple::Field(f) => f.has_embedded(s),
+            TSimple::Record(TRecord(fs)) => fs.iter().any(|(_k, v)| v.has_embedded(s)),
         }
     }
 }
@@ -309,16 +356,39 @@ impl TDefinition {
             }])
     }
 
-    pub fn has_embedded(&self, ctxt: &BundleContext) -> bool {
-        self._has_embedded(ctxt, &mut Set::new())
+    fn walk_state<'a, 'b>(&self, ctxt: &'a BundleContext<'b>) -> WalkState<'a, 'b> {
+        WalkState {
+            current_module_path: self.self_ref.module.clone(),
+            ctxt,
+            seen: Set::new(),
+        }
     }
 
-    fn _has_embedded(&self, ctxt: &BundleContext, seen: &mut Set<Ref>) -> bool {
+    pub fn language_types(&self, ctxt: &BundleContext) -> Set<String> {
+        let mut ts = Set::new();
+        self._language_types(&mut self.walk_state(ctxt), &mut ts);
+        ts
+    }
+
+    fn _language_types(&self, s: &mut WalkState, ts: &mut Set<String>) {
         match &self.body {
-            TDefinitionBody::Union(entries) =>
-                entries.iter().any(|(_k, v)| v.has_embedded(&self.self_ref.module, ctxt, seen)),
-            TDefinitionBody::Simple(t) =>
-                t.has_embedded(&self.self_ref.module, ctxt, seen),
+            TDefinitionBody::Union(entries) => entries.iter().for_each(|(_k, v)| v.language_types(s, ts)),
+            TDefinitionBody::Simple(t) => t.language_types(s, ts),
+        }
+    }
+
+    pub fn has_embedded(&self, ctxt: &BundleContext) -> bool {
+        self._has_embedded(&mut WalkState {
+            current_module_path: self.self_ref.module.clone(),
+            ctxt,
+            seen: Set::new(),
+        })
+    }
+
+    fn _has_embedded(&self, s: &mut WalkState) -> bool {
+        match &self.body {
+            TDefinitionBody::Union(entries) => entries.iter().any(|(_k, v)| v.has_embedded(s)),
+            TDefinitionBody::Simple(t) => t.has_embedded(s),
         }
     }
 }
diff --git a/implementations/rust/preserves-schema/src/compiler/unparsers.rs b/implementations/rust/preserves-schema/src/compiler/unparsers.rs
index 1bb4fca..eec1cb9 100644
--- a/implementations/rust/preserves-schema/src/compiler/unparsers.rs
+++ b/implementations/rust/preserves-schema/src/compiler/unparsers.rs
@@ -98,10 +98,7 @@ pub fn gen_definition_unparser(m: &mut ModuleContext, n: &str, d: &Definition) {
             }
 
             item(seq!["impl",
-                      anglebrackets![
-                          "'a",
-                          seq!["_L: Copy + Into<&'a ", ctxt.m.language_type(), ">"],
-                          seq![ctxt.m.any_type(), ": preserves::value::NestedValue + 'a"]],
+                      ctxt.m.parse_unparse_generic_decls(&ty),
                       " _support::Unparse", anglebrackets!["_L", ctxt.m.any_type()], " for ",
                       names::render_constructor(n), ty.generic_arg(ctxt.m), " ",
                       codeblock![
diff --git a/implementations/rust/preserves-schema/src/gen/schema.rs b/implementations/rust/preserves-schema/src/gen/schema.rs
index 4ca225e..b9c751e 100644
--- a/implementations/rust/preserves-schema/src/gen/schema.rs
+++ b/implementations/rust/preserves-schema/src/gen/schema.rs
@@ -126,7 +126,7 @@ fn parse_atom_kind_boolean<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<AtomKind, _support::ParseError> {
-    if value != &_ctxt.into().LIT_0_BOOLEAN { return Err(_support::ParseError::conformance_error("schema.AtomKind::Boolean")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_0_BOOLEAN { return Err(_support::ParseError::conformance_error("schema.AtomKind::Boolean")); }
     let _tmp0 = ();
     Ok(AtomKind::Boolean)
 }
@@ -136,7 +136,7 @@ fn parse_atom_kind_float<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<AtomKind, _support::ParseError> {
-    if value != &_ctxt.into().LIT_1_FLOAT { return Err(_support::ParseError::conformance_error("schema.AtomKind::Float")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_1_FLOAT { return Err(_support::ParseError::conformance_error("schema.AtomKind::Float")); }
     let _tmp0 = ();
     Ok(AtomKind::Float)
 }
@@ -146,7 +146,7 @@ fn parse_atom_kind_double<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<AtomKind, _support::ParseError> {
-    if value != &_ctxt.into().LIT_2_DOUBLE { return Err(_support::ParseError::conformance_error("schema.AtomKind::Double")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_2_DOUBLE { return Err(_support::ParseError::conformance_error("schema.AtomKind::Double")); }
     let _tmp0 = ();
     Ok(AtomKind::Double)
 }
@@ -156,7 +156,7 @@ fn parse_atom_kind_signed_integer<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<AtomKind, _support::ParseError> {
-    if value != &_ctxt.into().LIT_3_SIGNED_INTEGER { return Err(_support::ParseError::conformance_error("schema.AtomKind::SignedInteger")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_3_SIGNED_INTEGER { return Err(_support::ParseError::conformance_error("schema.AtomKind::SignedInteger")); }
     let _tmp0 = ();
     Ok(AtomKind::SignedInteger)
 }
@@ -166,7 +166,7 @@ fn parse_atom_kind_string<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<AtomKind, _support::ParseError> {
-    if value != &_ctxt.into().LIT_4_STRING { return Err(_support::ParseError::conformance_error("schema.AtomKind::String")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_4_STRING { return Err(_support::ParseError::conformance_error("schema.AtomKind::String")); }
     let _tmp0 = ();
     Ok(AtomKind::String)
 }
@@ -176,7 +176,7 @@ fn parse_atom_kind_byte_string<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<AtomKind, _support::ParseError> {
-    if value != &_ctxt.into().LIT_5_BYTE_STRING { return Err(_support::ParseError::conformance_error("schema.AtomKind::ByteString")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_5_BYTE_STRING { return Err(_support::ParseError::conformance_error("schema.AtomKind::ByteString")); }
     let _tmp0 = ();
     Ok(AtomKind::ByteString)
 }
@@ -186,7 +186,7 @@ fn parse_atom_kind_symbol<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<AtomKind, _support::ParseError> {
-    if value != &_ctxt.into().LIT_6_SYMBOL { return Err(_support::ParseError::conformance_error("schema.AtomKind::Symbol")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_6_SYMBOL { return Err(_support::ParseError::conformance_error("schema.AtomKind::Symbol")); }
     let _tmp0 = ();
     Ok(AtomKind::Symbol)
 }
@@ -215,13 +215,15 @@ impl<
 > _support::Unparse<_L, _Value> for AtomKind {
     fn unparse(&self, _ctxt: _L) -> _Value {
         match self {
-            AtomKind::Boolean => (&_ctxt.into().LIT_0_BOOLEAN).clone(),
-            AtomKind::Float => (&_ctxt.into().LIT_1_FLOAT).clone(),
-            AtomKind::Double => (&_ctxt.into().LIT_2_DOUBLE).clone(),
-            AtomKind::SignedInteger => (&_ctxt.into().LIT_3_SIGNED_INTEGER).clone(),
-            AtomKind::String => (&_ctxt.into().LIT_4_STRING).clone(),
-            AtomKind::ByteString => (&_ctxt.into().LIT_5_BYTE_STRING).clone(),
-            AtomKind::Symbol => (&_ctxt.into().LIT_6_SYMBOL).clone(),
+            AtomKind::Boolean => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_0_BOOLEAN).clone(),
+            AtomKind::Float => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_1_FLOAT).clone(),
+            AtomKind::Double => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_2_DOUBLE).clone(),
+            AtomKind::SignedInteger => (
+                &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_3_SIGNED_INTEGER
+            ).clone(),
+            AtomKind::String => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_4_STRING).clone(),
+            AtomKind::ByteString => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_5_BYTE_STRING).clone(),
+            AtomKind::Symbol => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_6_SYMBOL).clone(),
         }
     }
 }
@@ -266,7 +268,7 @@ impl<
 > _support::Parse<_L, _Value> for Binding<_Value> {
     fn parse(_ctxt: _L, value: &_Value) -> std::result::Result<Self, _support::ParseError> {
         let _tmp0 = value.value().to_record(None)?;
-        if _tmp0.label() != &_ctxt.into().LIT_7_NAMED { return Err(_support::ParseError::conformance_error("schema.Binding")); }
+        if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_7_NAMED { return Err(_support::ParseError::conformance_error("schema.Binding")); }
         let _tmp1 = ();
         if _tmp0.fields().len() < 2 { return Err(_support::ParseError::conformance_error("schema.Binding")); }
         let _tmp2 = (&_tmp0.fields()[0]).value().to_symbol()?;
@@ -283,7 +285,7 @@ impl<
     fn unparse(&self, _ctxt: _L) -> _Value {
         let Binding {name: _tmp0, pattern: _tmp1} = self;
         {
-            let mut _tmp2 = preserves::value::Record(vec![(&_ctxt.into().LIT_7_NAMED).clone()]);
+            let mut _tmp2 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_7_NAMED).clone()]);
             _tmp2.fields_vec_mut().push(preserves::value::Value::symbol(_tmp0).wrap());
             _tmp2.fields_vec_mut().push(_tmp1.unparse(_ctxt));
             _tmp2.finish().wrap()
@@ -327,7 +329,7 @@ impl<
 > _support::Parse<_L, _Value> for Bundle<_Value> {
     fn parse(_ctxt: _L, value: &_Value) -> std::result::Result<Self, _support::ParseError> {
         let _tmp0 = value.value().to_record(None)?;
-        if _tmp0.label() != &_ctxt.into().LIT_8_BUNDLE { return Err(_support::ParseError::conformance_error("schema.Bundle")); }
+        if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_8_BUNDLE { return Err(_support::ParseError::conformance_error("schema.Bundle")); }
         let _tmp1 = ();
         if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.Bundle")); }
         let _tmp2 = Modules::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -343,7 +345,7 @@ impl<
     fn unparse(&self, _ctxt: _L) -> _Value {
         let Bundle {modules: _tmp0} = self;
         {
-            let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_8_BUNDLE).clone()]);
+            let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_8_BUNDLE).clone()]);
             _tmp1.fields_vec_mut().push(_tmp0.unparse(_ctxt));
             _tmp1.finish().wrap()
         }
@@ -491,7 +493,7 @@ fn parse_compound_pattern_rec<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<CompoundPattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_9_REC { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::rec")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_9_REC { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::rec")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 2 { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::rec")); }
     let _tmp2 = NamedPattern::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -505,7 +507,7 @@ fn parse_compound_pattern_tuple<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<CompoundPattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_10_TUPLE { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::tuple")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_10_TUPLE { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::tuple")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::tuple")); }
     let _tmp3 = (&_tmp0.fields()[0]).value().to_sequence()?;
@@ -523,7 +525,7 @@ fn parse_compound_pattern_tuple_prefix<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<CompoundPattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_11_TUPLE_PREFIX { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::tuplePrefix")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_11_TUPLE_PREFIX { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::tuplePrefix")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 2 { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::tuplePrefix")); }
     let _tmp3 = (&_tmp0.fields()[0]).value().to_sequence()?;
@@ -542,7 +544,7 @@ fn parse_compound_pattern_dict<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<CompoundPattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_12_DICT { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::dict")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_12_DICT { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::dict")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.CompoundPattern::dict")); }
     let _tmp2 = DictionaryEntries::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -571,13 +573,13 @@ impl<
     fn unparse(&self, _ctxt: _L) -> _Value {
         match self {
             CompoundPattern::Rec {label: _tmp0, fields: _tmp1} => {
-                let mut _tmp2 = preserves::value::Record(vec![(&_ctxt.into().LIT_9_REC).clone()]);
+                let mut _tmp2 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_9_REC).clone()]);
                 _tmp2.fields_vec_mut().push(_tmp0.as_ref().unparse(_ctxt));
                 _tmp2.fields_vec_mut().push(_tmp1.as_ref().unparse(_ctxt));
                 _tmp2.finish().wrap()
             },
             CompoundPattern::Tuple {patterns: _tmp0} => {
-                let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_10_TUPLE).clone()]);
+                let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_10_TUPLE).clone()]);
                 _tmp1.fields_vec_mut().push(
                     {
                         let mut _tmp2 = std::vec::Vec::new();
@@ -590,7 +592,9 @@ impl<
                 _tmp1.finish().wrap()
             },
             CompoundPattern::TuplePrefix {fixed: _tmp0, variable: _tmp1} => {
-                let mut _tmp2 = preserves::value::Record(vec![(&_ctxt.into().LIT_11_TUPLE_PREFIX).clone()]);
+                let mut _tmp2 = preserves::value::Record(vec![(
+                    &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_11_TUPLE_PREFIX
+                ).clone()]);
                 _tmp2.fields_vec_mut().push(
                     {
                         let mut _tmp3 = std::vec::Vec::new();
@@ -604,7 +608,7 @@ impl<
                 _tmp2.finish().wrap()
             },
             CompoundPattern::Dict {entries: _tmp0} => {
-                let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_12_DICT).clone()]);
+                let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_12_DICT).clone()]);
                 _tmp1.fields_vec_mut().push(_tmp0.as_ref().unparse(_ctxt));
                 _tmp1.finish().wrap()
             },
@@ -728,7 +732,7 @@ fn parse_definition_or<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<Definition<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_13_OR { return Err(_support::ParseError::conformance_error("schema.Definition::or")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_13_OR { return Err(_support::ParseError::conformance_error("schema.Definition::or")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.Definition::or")); }
     let _tmp2 = (&_tmp0.fields()[0]).value().to_sequence()?;
@@ -753,7 +757,7 @@ fn parse_definition_and<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<Definition<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_14_AND { return Err(_support::ParseError::conformance_error("schema.Definition::and")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_14_AND { return Err(_support::ParseError::conformance_error("schema.Definition::and")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.Definition::and")); }
     let _tmp2 = (&_tmp0.fields()[0]).value().to_sequence()?;
@@ -802,7 +806,7 @@ impl<
     fn unparse(&self, _ctxt: _L) -> _Value {
         match self {
             Definition::Or {pattern_0: _tmp0, pattern_1: _tmp1, pattern_n: _tmp2} => {
-                let mut _tmp3 = preserves::value::Record(vec![(&_ctxt.into().LIT_13_OR).clone()]);
+                let mut _tmp3 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_13_OR).clone()]);
                 _tmp3.fields_vec_mut().push(
                     {
                         let mut _tmp4 = std::vec::Vec::new();
@@ -817,7 +821,7 @@ impl<
                 _tmp3.finish().wrap()
             },
             Definition::And {pattern_0: _tmp0, pattern_1: _tmp1, pattern_n: _tmp2} => {
-                let mut _tmp3 = preserves::value::Record(vec![(&_ctxt.into().LIT_14_AND).clone()]);
+                let mut _tmp3 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_14_AND).clone()]);
                 _tmp3.fields_vec_mut().push(
                     {
                         let mut _tmp4 = std::vec::Vec::new();
@@ -986,7 +990,7 @@ fn parse_embedded_type_name_false<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<EmbeddedTypeName, _support::ParseError> {
-    if value != &_ctxt.into().LIT_15_FALSE { return Err(_support::ParseError::conformance_error("schema.EmbeddedTypeName::false")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_15_FALSE { return Err(_support::ParseError::conformance_error("schema.EmbeddedTypeName::false")); }
     let _tmp0 = ();
     Ok(EmbeddedTypeName::False)
 }
@@ -1011,7 +1015,7 @@ impl<
     fn unparse(&self, _ctxt: _L) -> _Value {
         match self {
             EmbeddedTypeName::Ref(_tmp0) => _tmp0.as_ref().unparse(_ctxt),
-            EmbeddedTypeName::False => (&_ctxt.into().LIT_15_FALSE).clone(),
+            EmbeddedTypeName::False => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_15_FALSE).clone(),
         }
     }
 }
@@ -1424,7 +1428,7 @@ impl<
 > _support::Parse<_L, _Value> for Ref {
     fn parse(_ctxt: _L, value: &_Value) -> std::result::Result<Self, _support::ParseError> {
         let _tmp0 = value.value().to_record(None)?;
-        if _tmp0.label() != &_ctxt.into().LIT_16_REF { return Err(_support::ParseError::conformance_error("schema.Ref")); }
+        if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_16_REF { return Err(_support::ParseError::conformance_error("schema.Ref")); }
         let _tmp1 = ();
         if _tmp0.fields().len() < 2 { return Err(_support::ParseError::conformance_error("schema.Ref")); }
         let _tmp2 = ModulePath::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -1441,7 +1445,7 @@ impl<
     fn unparse(&self, _ctxt: _L) -> _Value {
         let Ref {module: _tmp0, name: _tmp1} = self;
         {
-            let mut _tmp2 = preserves::value::Record(vec![(&_ctxt.into().LIT_16_REF).clone()]);
+            let mut _tmp2 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_16_REF).clone()]);
             _tmp2.fields_vec_mut().push(_tmp0.unparse(_ctxt));
             _tmp2.fields_vec_mut().push(preserves::value::Value::symbol(_tmp1).wrap());
             _tmp2.finish().wrap()
@@ -1523,15 +1527,19 @@ impl<
 > _support::Parse<_L, _Value> for Schema<_Value> {
     fn parse(_ctxt: _L, value: &_Value) -> std::result::Result<Self, _support::ParseError> {
         let _tmp0 = value.value().to_record(None)?;
-        if _tmp0.label() != &_ctxt.into().LIT_17_SCHEMA { return Err(_support::ParseError::conformance_error("schema.Schema")); }
+        if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_17_SCHEMA { return Err(_support::ParseError::conformance_error("schema.Schema")); }
         let _tmp1 = ();
         if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.Schema")); }
         let _tmp2 = (&_tmp0.fields()[0]).value().to_dictionary()?;
-        let _tmp3 = _tmp2.get(&_ctxt.into().LIT_18_DEFINITIONS).ok_or_else(|| _support::ParseError::conformance_error("schema.Schema"))?;
+        let _tmp3 = _tmp2.get(
+            &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_18_DEFINITIONS
+        ).ok_or_else(|| _support::ParseError::conformance_error("schema.Schema"))?;
         let _tmp4 = Definitions::parse(_ctxt, _tmp3)?;
-        let _tmp5 = _tmp2.get(&_ctxt.into().LIT_19_EMBEDDED_TYPE).ok_or_else(|| _support::ParseError::conformance_error("schema.Schema"))?;
+        let _tmp5 = _tmp2.get(
+            &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_19_EMBEDDED_TYPE
+        ).ok_or_else(|| _support::ParseError::conformance_error("schema.Schema"))?;
         let _tmp6 = EmbeddedTypeName::parse(_ctxt, _tmp5)?;
-        let _tmp7 = _tmp2.get(&_ctxt.into().LIT_20_VERSION).ok_or_else(|| _support::ParseError::conformance_error("schema.Schema"))?;
+        let _tmp7 = _tmp2.get(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_20_VERSION).ok_or_else(|| _support::ParseError::conformance_error("schema.Schema"))?;
         let _tmp8 = Version::parse(_ctxt, _tmp7)?;
         Ok(Schema {definitions: _tmp4, embedded_type: _tmp6, version: _tmp8})
     }
@@ -1545,13 +1553,26 @@ impl<
     fn unparse(&self, _ctxt: _L) -> _Value {
         let Schema {definitions: _tmp0, embedded_type: _tmp1, version: _tmp2} = self;
         {
-            let mut _tmp3 = preserves::value::Record(vec![(&_ctxt.into().LIT_17_SCHEMA).clone()]);
+            let mut _tmp3 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_17_SCHEMA).clone()]);
             _tmp3.fields_vec_mut().push(
                 {
                     let mut _tmp4 = preserves::value::Map::new();
-                    _tmp4.insert((&_ctxt.into().LIT_18_DEFINITIONS).clone(), _tmp0.unparse(_ctxt));
-                    _tmp4.insert((&_ctxt.into().LIT_19_EMBEDDED_TYPE).clone(), _tmp1.unparse(_ctxt));
-                    _tmp4.insert((&_ctxt.into().LIT_20_VERSION).clone(), _tmp2.unparse(_ctxt));
+                    _tmp4.insert(
+                        (
+                            &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_18_DEFINITIONS
+                        ).clone(),
+                        _tmp0.unparse(_ctxt)
+                    );
+                    _tmp4.insert(
+                        (
+                            &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_19_EMBEDDED_TYPE
+                        ).clone(),
+                        _tmp1.unparse(_ctxt)
+                    );
+                    _tmp4.insert(
+                        (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_20_VERSION).clone(),
+                        _tmp2.unparse(_ctxt)
+                    );
                     preserves::value::Value::Dictionary(_tmp4).wrap()
                 }
             );
@@ -1747,7 +1768,7 @@ fn parse_simple_pattern_any<
     _L: Copy + Into<&'a crate::gen::Language<_Value>>,
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<SimplePattern<_Value>, _support::ParseError> {
-    if value != &_ctxt.into().LIT_21_ANY { return Err(_support::ParseError::conformance_error("schema.SimplePattern::any")); }
+    if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_21_ANY { return Err(_support::ParseError::conformance_error("schema.SimplePattern::any")); }
     let _tmp0 = ();
     Ok(SimplePattern::Any)
 }
@@ -1758,7 +1779,7 @@ fn parse_simple_pattern_atom<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<SimplePattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_22_ATOM { return Err(_support::ParseError::conformance_error("schema.SimplePattern::atom")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_22_ATOM { return Err(_support::ParseError::conformance_error("schema.SimplePattern::atom")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.SimplePattern::atom")); }
     let _tmp2 = AtomKind::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -1771,7 +1792,7 @@ fn parse_simple_pattern_embedded<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<SimplePattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_23_EMBEDDED { return Err(_support::ParseError::conformance_error("schema.SimplePattern::embedded")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_23_EMBEDDED { return Err(_support::ParseError::conformance_error("schema.SimplePattern::embedded")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.SimplePattern::embedded")); }
     let _tmp2 = SimplePattern::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -1784,7 +1805,7 @@ fn parse_simple_pattern_lit<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<SimplePattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_24_LIT { return Err(_support::ParseError::conformance_error("schema.SimplePattern::lit")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_24_LIT { return Err(_support::ParseError::conformance_error("schema.SimplePattern::lit")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.SimplePattern::lit")); }
     let _tmp2 = (&_tmp0.fields()[0]);
@@ -1797,7 +1818,7 @@ fn parse_simple_pattern_seqof<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<SimplePattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_25_SEQOF { return Err(_support::ParseError::conformance_error("schema.SimplePattern::seqof")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_25_SEQOF { return Err(_support::ParseError::conformance_error("schema.SimplePattern::seqof")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.SimplePattern::seqof")); }
     let _tmp2 = SimplePattern::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -1810,7 +1831,7 @@ fn parse_simple_pattern_setof<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<SimplePattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_26_SETOF { return Err(_support::ParseError::conformance_error("schema.SimplePattern::setof")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_26_SETOF { return Err(_support::ParseError::conformance_error("schema.SimplePattern::setof")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 1 { return Err(_support::ParseError::conformance_error("schema.SimplePattern::setof")); }
     let _tmp2 = SimplePattern::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -1823,7 +1844,7 @@ fn parse_simple_pattern_dictof<
     _Value: preserves::value::NestedValue + 'a
 >(_ctxt: _L, value: &_Value) -> std::result::Result<SimplePattern<_Value>, _support::ParseError> {
     let _tmp0 = value.value().to_record(None)?;
-    if _tmp0.label() != &_ctxt.into().LIT_27_DICTOF { return Err(_support::ParseError::conformance_error("schema.SimplePattern::dictof")); }
+    if _tmp0.label() != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_27_DICTOF { return Err(_support::ParseError::conformance_error("schema.SimplePattern::dictof")); }
     let _tmp1 = ();
     if _tmp0.fields().len() < 2 { return Err(_support::ParseError::conformance_error("schema.SimplePattern::dictof")); }
     let _tmp2 = SimplePattern::parse(_ctxt, (&_tmp0.fields()[0]))?;
@@ -1865,34 +1886,34 @@ impl<
 > _support::Unparse<_L, _Value> for SimplePattern<_Value> {
     fn unparse(&self, _ctxt: _L) -> _Value {
         match self {
-            SimplePattern::Any => (&_ctxt.into().LIT_21_ANY).clone(),
+            SimplePattern::Any => (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_21_ANY).clone(),
             SimplePattern::Atom {atom_kind: _tmp0} => {
-                let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_22_ATOM).clone()]);
+                let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_22_ATOM).clone()]);
                 _tmp1.fields_vec_mut().push(_tmp0.as_ref().unparse(_ctxt));
                 _tmp1.finish().wrap()
             },
             SimplePattern::Embedded {interface: _tmp0} => {
-                let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_23_EMBEDDED).clone()]);
+                let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_23_EMBEDDED).clone()]);
                 _tmp1.fields_vec_mut().push(_tmp0.as_ref().unparse(_ctxt));
                 _tmp1.finish().wrap()
             },
             SimplePattern::Lit {value: _tmp0} => {
-                let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_24_LIT).clone()]);
+                let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_24_LIT).clone()]);
                 _tmp1.fields_vec_mut().push(_tmp0.clone());
                 _tmp1.finish().wrap()
             },
             SimplePattern::Seqof {pattern: _tmp0} => {
-                let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_25_SEQOF).clone()]);
+                let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_25_SEQOF).clone()]);
                 _tmp1.fields_vec_mut().push(_tmp0.as_ref().unparse(_ctxt));
                 _tmp1.finish().wrap()
             },
             SimplePattern::Setof {pattern: _tmp0} => {
-                let mut _tmp1 = preserves::value::Record(vec![(&_ctxt.into().LIT_26_SETOF).clone()]);
+                let mut _tmp1 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_26_SETOF).clone()]);
                 _tmp1.fields_vec_mut().push(_tmp0.as_ref().unparse(_ctxt));
                 _tmp1.finish().wrap()
             },
             SimplePattern::Dictof {key: _tmp0, value: _tmp1} => {
-                let mut _tmp2 = preserves::value::Record(vec![(&_ctxt.into().LIT_27_DICTOF).clone()]);
+                let mut _tmp2 = preserves::value::Record(vec![(&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_27_DICTOF).clone()]);
                 _tmp2.fields_vec_mut().push(_tmp0.as_ref().unparse(_ctxt));
                 _tmp2.fields_vec_mut().push(_tmp1.as_ref().unparse(_ctxt));
                 _tmp2.finish().wrap()
@@ -1927,7 +1948,7 @@ impl<
     _Value: preserves::value::NestedValue + 'a
 > _support::Parse<_L, _Value> for Version {
     fn parse(_ctxt: _L, value: &_Value) -> std::result::Result<Self, _support::ParseError> {
-        if value != &_ctxt.into().LIT_28_1 { return Err(_support::ParseError::conformance_error("schema.Version")); }
+        if value != &<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_28_1 { return Err(_support::ParseError::conformance_error("schema.Version")); }
         let _tmp0 = ();
         Ok(Version)
     }
@@ -1940,6 +1961,6 @@ impl<
 > _support::Unparse<_L, _Value> for Version {
     fn unparse(&self, _ctxt: _L) -> _Value {
         let Version = self;
-        (&_ctxt.into().LIT_28_1).clone()
+        (&<_L as Into<&'a crate::gen::Language<_Value>>>::into(_ctxt).LIT_28_1).clone()
     }
 }
diff --git a/implementations/rust/preserves-schema/src/lib.rs b/implementations/rust/preserves-schema/src/lib.rs
index 8ff2948..ec34461 100644
--- a/implementations/rust/preserves-schema/src/lib.rs
+++ b/implementations/rust/preserves-schema/src/lib.rs
@@ -50,3 +50,31 @@ mod tests {
         Ok(())
     }
 }
+
+#[macro_export]
+macro_rules! define_language {
+    ($fname:ident () : $lang:ident < $default_value:ty > { $($field:ident : $($type:ident)::+ ,)* }) => {
+        pub struct $lang<N: $crate::support::preserves::value::NestedValue> {
+            $(pub $field: std::sync::Arc<$($type)::*<N>>),*
+        }
+
+        $(impl<'a, N: $crate::support::preserves::value::NestedValue> From<&'a $lang<N>> for &'a $($type)::*<N> {
+            fn from(v: &'a $lang<N>) -> Self {
+                &v.$field
+            }
+        })*
+
+        mod $fname {
+            use super::*;
+            lazy_static::lazy_static! {
+                pub static ref GLOBAL_LANG: $lang<$default_value> = $lang {
+                    $($field: std::sync::Arc::new($($type)::*::default())),*
+                };
+            }
+        }
+
+        pub fn $fname() -> &'static $lang<$default_value> {
+            &*$fname::GLOBAL_LANG
+        }
+    };
+}