diff --git a/code/compiler/12/ast.cpp b/code/compiler/12/ast.cpp
index 602d7fb..df996dc 100644
--- a/code/compiler/12/ast.cpp
+++ b/code/compiler/12/ast.cpp
@@ -50,10 +50,11 @@ void ast_lid::translate(global_scope& scope) {
 }
 
 void ast_lid::compile(const env_ptr& env, std::vector<instruction_ptr>& into) const {
+    auto mangled_name = this->env->get_mangled_name(id);
     into.push_back(instruction_ptr(
-        (env->has_variable(id) && !this->env->is_global(id)) ?
-            (instruction*) new instruction_push(env->get_offset(id)) :
-            (instruction*) new instruction_pushglobal(this->env->get_mangled_name(id))));
+        (env->has_variable(mangled_name) && !this->env->is_global(id)) ?
+            (instruction*) new instruction_push(env->get_offset(mangled_name)) :
+            (instruction*) new instruction_pushglobal(mangled_name)));
 }
 
 void ast_uid::print(int indent, std::ostream& to) const {
@@ -238,7 +239,7 @@ void ast_case::compile(const env_ptr& env, std::vector<instruction_ptr>& into) c
         } else if((cpat = dynamic_cast<pattern_constr*>(branch->pat.get()))) {
             env_ptr new_env = env;
             for(auto it = cpat->params.rbegin(); it != cpat->params.rend(); it++) {
-                new_env = env_ptr(new env_var(*it, new_env));
+                new_env = env_ptr(new env_var(branch->expr->env->get_mangled_name(*it), new_env));
             }
 
             branch_instructions.push_back(instruction_ptr(new instruction_split(
@@ -319,7 +320,7 @@ void ast_let::compile(const env_ptr& env, std::vector<instruction_ptr>& into) co
     into.push_back(instruction_ptr(new instruction_alloc(translated_definitions.size())));
     env_ptr new_env = env;
     for(auto& def : translated_definitions) {
-        new_env = env_ptr(new env_var(def.first, std::move(new_env)));
+        new_env = env_ptr(new env_var(definitions.env->get_mangled_name(def.first), std::move(new_env)));
     }
     int offset = translated_definitions.size() - 1;
     for(auto& def : translated_definitions) {