diff --git a/src/Entity.jl b/src/Entity.jl
index cdf97f175493cfd72d06fc20d9921c8bfe2f2939..f3766e406569bace325691bc3db1bf7fa85022c5 100644
--- a/src/Entity.jl
+++ b/src/Entity.jl
@@ -357,19 +357,19 @@ Return the id of the given `entity`
 """
 function get_id(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_id, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -379,19 +379,19 @@ Return the id of the given `parent`
 """
 function get_id(parent::Ref{_Parent})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_parent_get_id, CaosDB.library_name),
         Cint,
-        (Ref{_Parent}, Ptr{UInt8}),
+        (Ref{_Parent}, Ref{Ptr{UInt8}}),
         parent,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -401,19 +401,19 @@ Return the id of the given `property`
 """
 function get_id(property::Ref{_Property})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_property_get_id, CaosDB.library_name),
         Cint,
-        (Ref{_Property}, Ptr{UInt8}),
+        (Ref{_Property}, Ref{Ptr{UInt8}}),
         property,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -423,19 +423,19 @@ Return the role of the given `entity`.
 """
 function get_role(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_role, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -445,19 +445,19 @@ Return the name of the given `entity`
 """
 function get_name(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_name, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -467,19 +467,19 @@ Return the name of the given `parent`
 """
 function get_name(parent::Ref{_Parent})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_parent_get_name, CaosDB.library_name),
         Cint,
-        (Ref{_Parent}, Ptr{UInt8}),
+        (Ref{_Parent}, Ref{Ptr{UInt8}}),
         parent,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -489,19 +489,19 @@ Return the name of the given `property`
 """
 function get_name(property::Ref{_Property})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_property_get_name, CaosDB.library_name),
         Cint,
-        (Ref{_Property}, Ptr{UInt8}),
+        (Ref{_Property}, Ref{Ptr{UInt8}}),
         property,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -511,19 +511,19 @@ Return the description of the given `entity`
 """
 function get_description(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_description, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -533,19 +533,19 @@ Return the description of the given `parent`
 """
 function get_description(parent::Ref{_Parent})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_parent_get_description, CaosDB.library_name),
         Cint,
-        (Ref{_Parent}, Ptr{UInt8}),
+        (Ref{_Parent}, Ref{Ptr{UInt8}}),
         parent,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -555,19 +555,19 @@ Return the description of the given `property`
 """
 function get_description(property::Ref{_Property})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_property_get_description, CaosDB.library_name),
         Cint,
-        (Ref{_Property}, Ptr{UInt8}),
+        (Ref{_Property}, Ref{Ptr{UInt8}}),
         property,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -577,19 +577,19 @@ Return the description of the given `message`
 """
 function get_description(message::Ref{_Message})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_message_get_description, CaosDB.library_name),
         Cint,
-        (Ref{_Message}, Ptr{UInt8}),
+        (Ref{_Message}, Ref{Ptr{UInt8}}),
         message,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -599,19 +599,19 @@ Return the datatype of the given `entity`
 """
 function get_datatype(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_datatype, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -621,19 +621,19 @@ Return the datatype of the given `property`
 """
 function get_datatype(property::Ref{_Property})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_property_get_datatype, CaosDB.library_name),
         Cint,
-        (Ref{_Property}, Ptr{UInt8}),
+        (Ref{_Property}, Ref{Ptr{UInt8}}),
         property,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -643,19 +643,19 @@ Return the unit of the given `entity`
 """
 function get_unit(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_unit, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -665,19 +665,19 @@ Return the unit of the given `property`
 """
 function get_unit(property::Ref{_Property})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_property_get_unit, CaosDB.library_name),
         Cint,
-        (Ref{_Property}, Ptr{UInt8}),
+        (Ref{_Property}, Ref{Ptr{UInt8}}),
         property,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -687,19 +687,19 @@ Return the value of the given `entity`
 """
 function get_value(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_value, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -709,19 +709,19 @@ Return the value of the given `property`
 """
 function get_value(property::Ref{_Property})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_property_get_value, CaosDB.library_name),
         Cint,
-        (Ref{_Property}, Ptr{UInt8}),
+        (Ref{_Property}, Ref{Ptr{UInt8}}),
         property,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -731,19 +731,19 @@ Return the version_id of the given `entity`
 """
 function get_version_id(entity::Ref{_Entity})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_entity_get_version_id, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         entity,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """
@@ -776,19 +776,19 @@ Return the importance of the given `property`
 """
 function get_importance(property::Ref{_Property})
 
-    out = Vector{UInt8}(undef, 256)
+    out = Ref{Ptr{UInt8}}(Ptr{UInt8}())
 
     err_code = ccall(
         (:caosdb_entity_property_get_importance, CaosDB.library_name),
         Cint,
-        (Ref{_Entity}, Ptr{UInt8}),
+        (Ref{_Entity}, Ref{Ptr{UInt8}}),
         property,
         out,
     )
 
     CaosDB.Exceptions.evaluate_return_code(err_code)
 
-    return GC.@preserve out unsafe_string(pointer(out))
+    return unsafe_string(out[])
 end
 
 """