diff --git a/CMakeLists.txt b/CMakeLists.txt
index f3941d3..84709f5 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.25)
-project(blt-gp VERSION 0.0.26)
+project(blt-gp VERSION 0.0.27)
 
 option(ENABLE_ADDRSAN "Enable the address sanitizer" OFF)
 option(ENABLE_UBSAN "Enable the ub sanitizer" OFF)
diff --git a/examples/gp_test_2.cpp b/examples/gp_test_2.cpp
index 55c1eb3..5c64961 100644
--- a/examples/gp_test_2.cpp
+++ b/examples/gp_test_2.cpp
@@ -37,9 +37,11 @@ int main()
     type_system.register_type<float>();
     type_system.register_type<bool>();
     
-    type_system.add_operator(add);
-    type_system.add_operator(sub);
-    type_system.add_operator(mul);
-    type_system.add_operator(pro_div);
-    type_system.add_operator(lit);
+    program.add_operator(add);
+    program.add_operator(sub);
+    program.add_operator(mul);
+    program.add_operator(pro_div);
+    program.add_operator(lit, true);
+    
+    return 0;
 }
\ No newline at end of file
diff --git a/examples/main.cpp b/examples/main.cpp
index 10b3db5..7b67789 100644
--- a/examples/main.cpp
+++ b/examples/main.cpp
@@ -219,6 +219,7 @@ void test()
         std::cout << std::endl;
     }
     
+    // run the tree
     std::stack<float> process;
     std::stack<op> operators;
     
@@ -398,4 +399,6 @@ int main_old()
     std::cout << silly_op.operator()(alloc) << std::endl;
     
     std::cout << "Hello World!" << std::endl;
+    
+    return 0;
 }
\ No newline at end of file
diff --git a/include/blt/gp/operations.h b/include/blt/gp/operations.h
index c2a9556..51fe5ac 100644
--- a/include/blt/gp/operations.h
+++ b/include/blt/gp/operations.h
@@ -26,7 +26,7 @@
 
 namespace blt::gp
 {
-    template<typename Signature>
+    template<typename>
     class operation_t;
     
     template<typename Return, typename... Args>
diff --git a/include/blt/gp/program.h b/include/blt/gp/program.h
index b56e4d6..2f9da23 100644
--- a/include/blt/gp/program.h
+++ b/include/blt/gp/program.h
@@ -42,28 +42,96 @@
 
 namespace blt::gp
 {
+    static constexpr blt::size_t NONE_T = 0x0;
+    static constexpr blt::size_t STATIC_T = 0x1;
+    static constexpr blt::size_t TERMINAL_T = 0x2;
+    
     class gp_program
     {
         public:
-            explicit gp_program(type_system& system, std::mt19937_64 engine): system(system), engine(engine)
+            /**
+             * Note about context size: This is required as context is passed to every operator in the GP tree, this context will be provided by your
+             * call to one of the evaluator functions. This was the nicest way to provide this as C++ lacks reflection
+             *
+             * @param system type system to use in tree generation
+             * @param engine random engine to use throughout the program. TODO replace this with something better
+             * @param context_size number of arguments which are always present as "context" to the GP system / operators
+             */
+            explicit gp_program(type_system& system, std::mt19937_64 engine):
+                    system(system), engine(engine)
             {}
             
+            void generate_tree();
+            
+            [[nodiscard]] inline std::mt19937_64& get_random()
+            {
+                return engine;
+            }
+            
             [[nodiscard]] inline type_system& get_typesystem()
             {
                 return system;
             }
             
-            void generate_tree();
-            
-            inline std::mt19937_64& get_random()
+            inline operator_id select_terminal(type_id id)
             {
-                return engine;
+                std::uniform_int_distribution<blt::size_t> dist(0, terminals[id].size() - 1);
+                return terminals[id][dist(engine)];
+            }
+            
+            inline operator_id select_non_terminal(type_id id)
+            {
+                std::uniform_int_distribution<blt::size_t> dist(0, non_terminals[id].size() - 1);
+                return non_terminals[id][dist(engine)];
+            }
+            
+            inline std::vector<type>& get_argument_types(operator_id id)
+            {
+                return argument_types[id];
+            }
+            
+            inline std::vector<operator_id>& get_type_terminals(type_id id)
+            {
+                return terminals[id];
+            }
+            
+            inline std::vector<operator_id>& get_type_non_terminals(type_id id)
+            {
+                return non_terminals[id];
+            }
+            
+            inline bool is_static(operator_id id)
+            {
+                return static_types.contains(static_cast<blt::size_t>(id));
+            }
+            
+            template<typename Return, typename... Args>
+            void add_operator(const operation_t<Return(Args...)>& op, bool is_static = false)
+            {
+                auto return_type_id = system.get_type<Return>().id();
+                auto operator_id = blt::gp::operator_id(operators.size());
+                
+                auto& operator_list = op.get_argc() == 0 ? terminals : non_terminals;
+                operator_list[return_type_id].push_back(operator_id);
+                
+                (argument_types[operator_id].push_back(system.get_type<Args>()), ...);
+                operators.push_back(op.make_callable());
+                if (is_static)
+                    static_types.insert(operator_id);
             }
         
         private:
             type_system& system;
             blt::gp::stack_allocator alloc;
             std::mt19937_64 engine;
+            
+            // indexed from return TYPE ID, returns index of operator
+            blt::expanding_buffer<std::vector<operator_id>> terminals;
+            blt::expanding_buffer<std::vector<operator_id>> non_terminals;
+            // indexed from OPERATOR ID (operator number)
+            blt::expanding_buffer<std::vector<type>> argument_types;
+            blt::hashset_t<operator_id> static_types;
+            std::vector<std::function<void(stack_allocator&)>> operators;
     };
     
 }
diff --git a/include/blt/gp/typesystem.h b/include/blt/gp/typesystem.h
index 1be619f..84cc22e 100644
--- a/include/blt/gp/typesystem.h
+++ b/include/blt/gp/typesystem.h
@@ -112,55 +112,28 @@ namespace blt::gp
                     itr = itr++;
                 return itr->second;
             }
-            
-            inline operator_id select_terminal(std::mt19937_64& engine, type_id id)
-            {
-                std::uniform_int_distribution<blt::size_t> dist(0, terminals[id].size() - 1);
-                return terminals[id][dist(engine)];
-            }
-            
-            inline operator_id select_non_terminal(std::mt19937_64& engine, type_id id)
-            {
-                std::uniform_int_distribution<blt::size_t> dist(0, non_terminals[id].size() - 1);
-                return non_terminals[id][dist(engine)];
-            }
-            
-            inline std::vector<type>& get_argument_types(operator_id id)
-            {
-                return argument_types[id];
-            }
-            
-            inline std::vector<operator_id>& get_type_terminals(type_id id)
-            {
-                return terminals[id];
-            }
-            
-            inline std::vector<operator_id>& get_type_non_terminals(type_id id)
-            {
-                return non_terminals[id];
-            }
-            
-            template<typename Return, typename... Args>
-            void add_operator(const operation_t<Return(Args...)>& op)
-            {
-                auto return_type_id = get_type<Return>().id();
-                auto& operator_list = op.get_argc() == 0 ? terminals : non_terminals;
-                operator_list[return_type_id].push_back(operators.size());
-                
-                auto operator_index = operators.size();
-                (argument_types[operator_index].push_back(get_type<Args>()), ...);
-                operators.push_back(op.make_callable());
-            }
         
         private:
             blt::hashmap_t<std::string, type> types;
-            // indexed from return TYPE ID, returns index of operator
-            blt::expanding_buffer<std::vector<operator_id>> terminals;
-            blt::expanding_buffer<std::vector<operator_id>> non_terminals;
-            // indexed from OPERATOR ID (operator number)
-            blt::expanding_buffer<std::vector<type>> argument_types;
-            std::vector<std::function<void(stack_allocator&)>> operators;
     };
 }
 
+template<>
+struct std::hash<blt::gp::operator_id>
+{
+    std::size_t operator()(const blt::gp::operator_id& s) const noexcept
+    {
+        return std::hash<blt::gp::operator_id::value_type>{}(s);
+    }
+};
+
+template<>
+struct std::hash<blt::gp::type_id>
+{
+    std::size_t operator()(const blt::gp::type_id& s) const noexcept
+    {
+        return std::hash<blt::gp::type_id::value_type>{}(s);
+    }
+};
+
 #endif //BLT_GP_TYPESYSTEM_H
diff --git a/lib/blt b/lib/blt
index 1ca46b9..cc788e9 160000
--- a/lib/blt
+++ b/lib/blt
@@ -1 +1 @@
-Subproject commit 1ca46b9d7bb9621a2f7d02a9ca1eff99e91e3f1a
+Subproject commit cc788e98f4a739f450f487f6a7c758990128a698
diff --git a/src/generators.cpp b/src/generators.cpp
index 9bbc46d..53d5ffc 100644
--- a/src/generators.cpp
+++ b/src/generators.cpp
@@ -38,9 +38,9 @@ namespace blt::gp
         do
         {
             base_type = system.select_type(program.get_random());
-        } while (system.get_type_non_terminals(base_type.id()).empty());
+        } while (program.get_type_non_terminals(base_type.id()).empty());
         
-        tree_generator.emplace(system.select_non_terminal(program.get_random(), base_type.id()), 0);
+        tree_generator.emplace(program.select_non_terminal(base_type.id()), 0);
         
         return tree_generator;
     }