diff --git a/CMakeLists.txt b/CMakeLists.txt
index 84709f5..5c0fd5e 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -1,5 +1,5 @@
 cmake_minimum_required(VERSION 3.25)
-project(blt-gp VERSION 0.0.27)
+project(blt-gp VERSION 0.0.28)
 
 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 5c64961..894e2ad 100644
--- a/examples/gp_test_2.cpp
+++ b/examples/gp_test_2.cpp
@@ -20,7 +20,6 @@
 static constexpr long SEED = 41912;
 
 blt::gp::type_system type_system;
-std::random_device dev;
 blt::gp::gp_program program(type_system, std::mt19937_64{SEED}); // NOLINT
 
 blt::gp::operation_t add([](float a, float b) { return a + b; });
@@ -37,11 +36,14 @@ int main()
     type_system.register_type<float>();
     type_system.register_type<bool>();
     
-    program.add_operator(add);
-    program.add_operator(sub);
-    program.add_operator(mul);
-    program.add_operator(pro_div);
-    program.add_operator(lit, true);
+    blt::gp::gp_operations silly{type_system};
+    silly.add_operator(add);
+    silly.add_operator(sub);
+    silly.add_operator(mul);
+    silly.add_operator(pro_div);
+    silly.add_operator(lit, true);
+    
+    program.set_operations(std::move(silly));
     
     return 0;
 }
\ No newline at end of file
diff --git a/include/blt/gp/operations.h b/include/blt/gp/operations.h
index 51fe5ac..480f3f5 100644
--- a/include/blt/gp/operations.h
+++ b/include/blt/gp/operations.h
@@ -23,9 +23,66 @@
 #include <blt/gp/typesystem.h>
 #include <blt/gp/stack.h>
 #include <functional>
+#include <type_traits>
 
 namespace blt::gp
 {
+    namespace detail
+    {
+        using callable_t = std::function<void(void*, stack_allocator&)>;
+        struct empty_t
+        {
+        };
+    }
+    
+    template<typename Return, typename... Args>
+    struct call_with
+    {
+        template<blt::u64 index>
+        [[nodiscard]] inline constexpr static blt::size_t getByteOffset()
+        {
+            blt::size_t offset = 0;
+            blt::size_t current_index = 0;
+            ((offset += (current_index++ > index ? stack_allocator::aligned_size<Args>() : 0)), ...);
+            return offset;
+        }
+        
+        template<typename Func, blt::u64... indices, typename... ExtraArgs>
+        inline static constexpr Return exec_sequence_to_indices(Func&& func, stack_allocator& allocator, std::integer_sequence<blt::u64, indices...>,
+                                                                ExtraArgs&& ... args)
+        {
+            // expands Args and indices, providing each argument with its index calculating the current argument byte offset
+            return std::forward<Func>(func)(std::forward<ExtraArgs>(args)..., allocator.from<Args>(getByteOffset<indices>())...);
+        }
+        
+        template<typename Func, typename... ExtraArgs>
+        Return operator()(Func&& func, stack_allocator& allocator, ExtraArgs&& ... args)
+        {
+            constexpr auto seq = std::make_integer_sequence<blt::u64, sizeof...(Args)>();
+            Return ret = exec_sequence_to_indices(std::forward<Func>(func), allocator, seq, std::forward<ExtraArgs>(args)...);
+            allocator.call_destructors<Args...>();
+            allocator.pop_bytes((stack_allocator::aligned_size<Args>() + ...));
+            return ret;
+        }
+    };
+    
+    template<typename First, typename... Args>
+    struct first_arg
+    {
+        using type = First;
+    };
+    
+    template<>
+    struct first_arg<void>
+    {
+    };
+    
+    template<typename Return, typename, typename... Args>
+    struct call_without_first : public call_with<Return, Args...>
+    {
+        using call_with<Return, Args...>::call_with;
+    };
+    
     template<typename>
     class operation_t;
     
@@ -43,22 +100,6 @@ namespace blt::gp
             constexpr explicit operation_t(const Functor& functor): func(functor)
             {}
             
-            template<blt::u64 index>
-            [[nodiscard]] inline constexpr static blt::size_t getByteOffset()
-            {
-                blt::size_t offset = 0;
-                blt::size_t current_index = 0;
-                ((offset += (current_index++ > index ? stack_allocator::aligned_size<Args>() : 0)), ...);
-                return offset;
-            }
-            
-            template<blt::u64... indices>
-            inline constexpr Return exec_sequence_to_indices(stack_allocator& allocator, std::integer_sequence<blt::u64, indices...>) const
-            {
-                // expands Args and indices, providing each argument with its index calculating the current argument byte offset
-                return func(allocator.from<Args>(getByteOffset<indices>())...);
-            }
-            
             [[nodiscard]] constexpr inline Return operator()(stack_allocator& allocator) const
             {
                 if constexpr (sizeof...(Args) == 0)
@@ -66,18 +107,47 @@ namespace blt::gp
                     return func();
                 } else
                 {
-                    constexpr auto seq = std::make_integer_sequence<blt::u64, sizeof...(Args)>();
-                    Return ret = exec_sequence_to_indices(allocator, seq);
-                    allocator.call_destructors<Args...>();
-                    allocator.pop_bytes((stack_allocator::aligned_size<Args>() + ...));
-                    return ret;
+                    return call_with<Return, Args...>()(func, allocator);
                 }
             }
             
-            [[nodiscard]] std::function<void(stack_allocator&)> make_callable() const
+            [[nodiscard]] constexpr inline Return operator()(void* context, stack_allocator& allocator) const
             {
-                return [this](stack_allocator& values) {
-                    values.push(this->operator()(values));
+                // should be an impossible state
+                if constexpr (sizeof...(Args) == 0)
+                {
+                    BLT_ABORT("Cannot pass context to function without arguments!");
+                }
+                auto& ctx_ref = *static_cast<typename first_arg<Args...>::type*>(context);
+                if constexpr (sizeof...(Args) == 1)
+                {
+                    return func(ctx_ref);
+                } else
+                {
+                    return call_without_first<Return, Args...>()(func, allocator, ctx_ref);
+                }
+            }
+            
+            template<typename Context>
+            [[nodiscard]] detail::callable_t make_callable() const
+            {
+                return [this](void* context, stack_allocator& values) {
+                    if constexpr (sizeof...(Args) == 0)
+                    {
+                        values.push(this->operator()(values));
+                    } else
+                    {
+                        // annoying hack.
+                        if constexpr (std::is_same_v<Context, typename first_arg<Args...>::type>)
+                        {
+                            // first arg is context
+                            values.push(this->operator()(context, values));
+                        } else
+                        {
+                            // first arg isn't context
+                            values.push(this->operator()(values));
+                        }
+                    }
                 };
             }
             
@@ -101,7 +171,7 @@ namespace blt::gp
     operation_t(Lambda) -> operation_t<decltype(&Lambda::operator())>;
     
     template<typename Return, typename... Args>
-    operation_t(Return (*)(Args...)) -> operation_t<Return(Args...)>;
+    operation_t(Return(*)(Args...)) -> operation_t<Return(Args...)>;
 
 //    templat\e<typename Return, typename Class, typename... Args>
 //    operation_t<Return(Args...)> make_operator(Return (Class::*)(Args...) const lambda)
diff --git a/include/blt/gp/program.h b/include/blt/gp/program.h
index 2f9da23..826c847 100644
--- a/include/blt/gp/program.h
+++ b/include/blt/gp/program.h
@@ -46,6 +46,42 @@ namespace blt::gp
     static constexpr blt::size_t STATIC_T = 0x1;
     static constexpr blt::size_t TERMINAL_T = 0x2;
     
+    template<typename Context = detail::empty_t>
+    class gp_operations
+    {
+            friend class gp_program;
+        
+        public:
+            explicit gp_operations(type_system& system): system(system)
+            {}
+            
+            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.template make_callable<Context>());
+                if (is_static)
+                    static_types.insert(operator_id);
+            }
+        
+        private:
+            type_system& system;
+            
+            // 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<detail::callable_t> operators;
+    };
+    
     class gp_program
     {
         public:
@@ -105,19 +141,14 @@ namespace blt::gp
                 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)
+            template<typename Context>
+            inline void set_operations(gp_operations<Context>&& op)
             {
-                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);
+                terminals = std::move(op.terminals);
+                non_terminals = std::move(op.non_terminals);
+                argument_types = std::move(op.argument_types);
+                static_types = std::move(op.static_types);
+                operators = std::move(op.operators);
             }
         
         private:
@@ -131,7 +162,7 @@ namespace blt::gp
             // 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;
+            std::vector<detail::callable_t> operators;
     };
     
 }
diff --git a/lib/blt b/lib/blt
index cc788e9..ac163a3 160000
--- a/lib/blt
+++ b/lib/blt
@@ -1 +1 @@
-Subproject commit cc788e98f4a739f450f487f6a7c758990128a698
+Subproject commit ac163a34b9d70346df80fcac44054e8dffe9ad43
diff --git a/src/generators.cpp b/src/generators.cpp
index 53d5ffc..5e63cda 100644
--- a/src/generators.cpp
+++ b/src/generators.cpp
@@ -40,13 +40,13 @@ namespace blt::gp
             base_type = system.select_type(program.get_random());
         } while (program.get_type_non_terminals(base_type.id()).empty());
         
-        tree_generator.emplace(program.select_non_terminal(base_type.id()), 0);
+        tree_generator.push(stack{program.select_non_terminal(base_type.id()), 0});
         
         return tree_generator;
     }
     
     template<typename Func>
-    tree_t create_tree(Func func, gp_program& program, blt::size_t min_depth, blt::size_t max_depth)
+    tree_t create_tree(Func, gp_program& program, blt::size_t, blt::size_t)
     {
         std::stack<stack> tree_generator = get_base_generator(program);
         tree_t tree;