diff --git a/tests/zecsy.cpp b/tests/zecsy.cpp
index f6135e8..a5c8c92 100644
--- a/tests/zecsy.cpp
+++ b/tests/zecsy.cpp
@@ -39,16 +39,18 @@ TEST_CASE("Entity #0 should be reserved and never used")
     REQUIRE_FALSE(entity().is_alive());
 }
 
+//TODO: doesn't make sense anymore? (I stopped limitting amount of entities)
 TEST_CASE("World should throw on id overflow")
 {
-    world w;
-
-    for(int i = 0; i < MAX_ZECSY_ENTITIES; ++i)
-    {
-        w.make_entity();
-    }
-
-    REQUIRE_THROWS(w.make_entity());
+    /*world w;*/
+    /**/
+    /*for(int i = 0; i < MAX_ZECSY_ENTITIES; ++i)*/
+    /*{*/
+    /*    w.make_entity();*/
+    /*}*/
+    /**/
+    /*REQUIRE_THROWS(w.make_entity());*/
+    REQUIRE(true);
 }
 
 struct ChoosenOne
diff --git a/zecsy.hpp b/zecsy.hpp
index 0566cc9..8f534ee 100644
--- a/zecsy.hpp
+++ b/zecsy.hpp
@@ -1,21 +1,17 @@
 #pragma once
 #include <catch2/internal/catch_console_colour.hpp>
 #include <cstdint>
-#include <bitset>
 #include <format>
 #include <queue>
 #include <stdexcept>
 #include <typeindex>
 #include <unordered_map>
-
-#ifndef MAX_ZECSY_ENTITIES
-    #define MAX_ZECSY_ENTITIES 65536
-#endif // !MAX_ZECSY_ENTITIES
-
+#include <unordered_set>
 
 namespace zecsy 
 {
     using entity_id = uint64_t;
+    using entities_set = std::unordered_set<entity_id>; 
 
     class entity final
     {
@@ -46,8 +42,6 @@ namespace zecsy
         class world* w = nullptr;
     };
 
-    using zecsy_bits = std::bitset<MAX_ZECSY_ENTITIES + 1>;
-
     class component_storage
     {
     public:
@@ -80,7 +74,7 @@ namespace zecsy
         void remove(entity_id e);
     private:
         using comp_index = std::type_index;
-        using comp_to_bitset = std::unordered_map<comp_index, zecsy_bits>;
+        using comp_to_entities_set = std::unordered_map<comp_index, entities_set>;
         using entity_to_index = std::unordered_map<entity_id, size_t>;
 
         using comp_to_entity_dict = std::unordered_map<comp_index, 
@@ -92,8 +86,8 @@ namespace zecsy
         using comp_to_reusable_ids = std::unordered_map<comp_index, 
               std::queue<size_t>>;
 
-        comp_to_bitset bitset_dict;
-        comp_to_entity_dict entity_dict; 
+        comp_to_entities_set entities_dict;
+        comp_to_entity_dict indices_dict; 
         comp_to_storage storage_dict;
         comp_to_reusable_ids reusable_id_queues;
     };
@@ -120,7 +114,7 @@ namespace zecsy
         template<typename... T>
         void remove(entity_id e);
     private:
-        zecsy_bits entities_bitset;
+        entities_set alive_entities;
         entity_id entity_counter = 0;
         component_storage storage;
     };
@@ -143,33 +137,27 @@ namespace zecsy
     inline entity world::make_entity()
     {
         auto id = ++entity_counter;
-        
-        if(id > MAX_ZECSY_ENTITIES)
-        {
-            throw std::runtime_error(std::format("Entity id {} exceeds " 
-                        "MAX_ZECSY_ENTITIES ({})", id, MAX_ZECSY_ENTITIES));
-        }
+        alive_entities.emplace(id);
 
-        entities_bitset.set(id);
         return entity(this, id);
     }
 
     inline void world::destroy_entity(entity_id e)
     {
-        entities_bitset.reset(e);
+        alive_entities.erase(e);
     }
 
     inline bool world::is_alive(entity_id e) const
     {
-        return entities_bitset.test(e);
+        return alive_entities.contains(e);
     }
 
     template<typename T>
     inline bool component_storage::has(entity_id e) const
     {
-        if(bitset_dict.contains(typeid(T)))
+        if(entities_dict.contains(typeid(T)))
         {
-            return bitset_dict.at(typeid(T)).test(e);
+            return entities_dict.at(typeid(T)).contains(e);
         }
         return false;
     }
@@ -183,7 +171,7 @@ namespace zecsy
                         e, typeid(T).name()));
         }
 
-        auto index = entity_dict[typeid(T)].at(e);
+        auto index = indices_dict[typeid(T)].at(e);
         
         auto* ptr = reinterpret_cast<T*>(&storage_dict[typeid(T)][0]);
         ptr += index;
@@ -218,7 +206,7 @@ namespace zecsy
     template<typename T>
     inline void component_storage::set(entity_id e, const T& comp)
     {
-        bitset_dict[typeid(T)].set(e);
+        entities_dict[typeid(T)].emplace(e);
 
         auto& storage = storage_dict[typeid(T)];
 
@@ -233,7 +221,7 @@ namespace zecsy
             void* ptr = &storage[0] + old_size;
             new(ptr) T(comp);
 
-            entity_dict[typeid(T)][e] = old_size / T_size;
+            indices_dict[typeid(T)][e] = old_size / T_size;
             return;
         }
 
@@ -243,7 +231,7 @@ namespace zecsy
         auto ptr = reinterpret_cast<T*>(&storage[0]);
         new(ptr + index) T(comp);
 
-        entity_dict[typeid(T)][e] = index;
+        indices_dict[typeid(T)][e] = index;
     }
     
     template<typename... T>
@@ -272,9 +260,9 @@ namespace zecsy
             return;
         }
 
-        bitset_dict[typeid(T)].reset(e);
-        reusable_id_queues[typeid(T)].push(entity_dict[typeid(T)][e]);
-        entity_dict[typeid(T)].erase(e);
+        entities_dict[typeid(T)].erase(e);
+        reusable_id_queues[typeid(T)].push(indices_dict[typeid(T)][e]);
+        indices_dict[typeid(T)].erase(e);
     }
 
     template<typename... T>