diff --git a/Cargo.toml b/Cargo.toml
index a940b1b1ec..95a8901253 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -536,4 +536,24 @@ version = "0.1.83"
 [workspace.dependencies.tokio]
 version = "1.41.0"
 features = []
-default-features = false
\ No newline at end of file
+default-features = false
+
+[workspace.dependencies.anyhow]
+version = "~1.0"
+# features = []
+# default-features = false
+
+[workspace.dependencies.thiserror]
+version = "~1.0"
+# features = []
+# default-features = false
+
+[workspace.dependencies.hashbrown]
+version = "~0.14.3"
+# optional = true
+default-features = false
+# features = [ "default" ]
+
+[workspace.dependencies.paste]
+version = "~1.0.14"
+default-features = false
diff --git a/module/core/collection_tools/Cargo.toml b/module/core/collection_tools/Cargo.toml
index 86dcfa51b3..d69009a758 100644
--- a/module/core/collection_tools/Cargo.toml
+++ b/module/core/collection_tools/Cargo.toml
@@ -11,16 +11,14 @@ documentation = "https://docs.rs/collection_tools"
 repository = "https://github.com/Wandalen/wTools/tree/master/module/core/collection_tools"
 homepage = "https://github.com/Wandalen/wTools/tree/master/module/core/collection_tools"
 description = """
-Collection of general purpose tools to manipulate collections( containers like Vec/HashMap/HashSet ).
+General purpose tools to manipulate collections( containers like Vec/HashMap/HashSet ).
 """
 categories = [ "algorithms", "development-tools" ]
 keywords = [ "fundamental", "general-purpose" ]
 
-
 [lints]
 workspace = true
 
-
 [package.metadata.docs.rs]
 features = [ "full" ]
 all-features = false
@@ -28,31 +26,26 @@ all-features = false
 [features]
 
 no_std = [
-  # "test_tools/no_std",
 ]
 
 use_alloc = [
-  "no_std", # qqq : for Anton : why is that better? -- use_alloc means that we do not use std, but alloc and hashbrown
+  "no_std",
   "hashbrown",
-  # "test_tools/use_alloc", // why is it needed? -- not needed, removed
 ]
 
 default = [
   "enabled",
-  # "reexports",
   "collection_constructors",
   "collection_into_constructors",
 ]
 
 full = [
   "enabled",
-  # "reexports",
   "collection_constructors",
   "collection_into_constructors",
 ]
 
 enabled = []
-# reexports = []
 
 # Collection constructors, like `hmap!{ "key" => "val" }`
 collection_constructors = []
@@ -63,7 +56,7 @@ collection_into_constructors = []
 [dependencies]
 
 ## external
-hashbrown = { version = "~0.14.3", optional = true, default-features = false, features = [ "default" ] }
+hashbrown = { workspace = true, optional = true, default-features = false, features = [ "default" ] }
 
 [dev-dependencies]
 test_tools = { workspace = true }
diff --git a/module/core/collection_tools/Readme.md b/module/core/collection_tools/Readme.md
index 1430c6d6ef..2b6f2b0ab6 100644
--- a/module/core/collection_tools/Readme.md
+++ b/module/core/collection_tools/Readme.md
@@ -5,7 +5,7 @@
  [![experimental](https://raster.shields.io/static/v1?label=&message=experimental&color=orange)](https://github.com/emersion/stability-badges#experimental) [![rust-status](https://github.com/Wandalen/wTools/actions/workflows/module_collection_tools_push.yml/badge.svg)](https://github.com/Wandalen/wTools/actions/workflows/module_collection_tools_push.yml) [![docs.rs](https://img.shields.io/docsrs/collection_tools?color=e3e8f0&logo=docs.rs)](https://docs.rs/collection_tools) [![Open in Gitpod](https://raster.shields.io/static/v1?label=try&message=online&color=eee&logo=gitpod&logoColor=eee)](https://gitpod.io/#RUN_PATH=.,SAMPLE_FILE=module%2Fcore%2Fcollection_tools%2Fexamples%2Fcollection_tools_trivial.rs,RUN_POSTFIX=--example%20collection_tools_trivial/https://github.com/Wandalen/wTools) [![discord](https://img.shields.io/discord/872391416519737405?color=eee&logo=discord&logoColor=eee&label=ask)](https://discord.gg/m3YfbXpUUY)
 <!--{ generate.module_header.end }-->
 
-Collection of general purpose tools to manipulate collections( containers like Vec/HashMap/HashSet... ).
+General purpose tools to manipulate collections( containers like Vec/HashMap/HashSet... ).
 
 ### Basic Use Case :: Variadic Constructors for Collections
 
@@ -71,7 +71,7 @@ assert_eq!( meta_list, meta_list );
 
 ### Basic Use Case :: `no_std` `HashSet` / `HashMap`
 
-When implementing a `no_std` environment with the `use_alloc` feature in your Rust project, you'll encounter a challenge: collections like `Vec` are imported differently depending on the availability of the `std` library. Moreover, to use data structures such as `HashSet` or `HashMap` in a `no_std` context, it's necessary to depend on third-party crates, as these are not provided by the `alloc` crate directly. This crate aims to simplify the process of designing Rust libraries or applications that require these collections in a `no_std` environment, offering a more streamlined approach to working with dynamic data structures without the standard library.
+When implementing a `no_std` ( `!use_std` ) environment with the `use_alloc` feature in your Rust project, you'll encounter a challenge: collections like `Vec` are imported differently depending on the availability of the `std` library. Moreover, to use data structures such as `HashSet` or `HashMap` in a `no_std` context, it's necessary to depend on third-party crates, as these are not provided by the `alloc` crate directly. This crate aims to simplify the process of designing Rust libraries or applications that require these collections in a `no_std` environment, offering a more streamlined approach to working with dynamic data structures without the standard library.
 
 You can do
 
@@ -98,7 +98,7 @@ Instead of
 # #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
 # {
 
-#[ cfg( feature = "use_alloc" ) ]
+#[ cfg( all( feature = "no_std", feature = "use_alloc" ) ) ]
 use hashbrown::HashSet; // a `no_std` replacement for `HashSet`
 #[ cfg( not( feature = "no_std" ) ) ]
 use std::collections::HashSet;
@@ -120,7 +120,8 @@ While strict macros require you to have all members of the same type, more relax
 
 For example:
 ```rust
-# #[ cfg( all( feature = "enabled", feature = "collection_into_constructors", any( not( feature = "no_std" ), feature = "use_alloc" ) ) ) ]
+# #[ cfg( all( feature = "enabled", feature = "collection_into_constructors" ) ) ]
+# #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
 # {
 use std::borrow::Cow;
 let vec : Vec< String > = collection_tools::into_vec!( "&str", "String".to_string(), Cow::from( "Cow" ) );
diff --git a/module/core/collection_tools/examples/collection_tools_trivial.rs b/module/core/collection_tools/examples/collection_tools_trivial.rs
index 8a11bb85bf..79ff09bf0d 100644
--- a/module/core/collection_tools/examples/collection_tools_trivial.rs
+++ b/module/core/collection_tools/examples/collection_tools_trivial.rs
@@ -19,18 +19,15 @@
 //! a `HashMap`, making your code cleaner and more concise. This is particularly useful in cases
 //! where you need to define a map with a known set of key-value pairs upfront.
 
-#[ cfg( not( all
-(
-//   not( feature = "use_alloc" ) ) ],
-  all( feature = "enabled", feature = "collection_constructors" ),
-  any( not( feature = "no_std" ), feature = "use_alloc" )
+#[ cfg( not( all(
+  feature = "enabled",
+  feature = "collection_constructors",
+  any( feature = "use_alloc", not( feature = "no_std" ) )
 )))]
-fn main(){}
+fn main() {}
 
-// zzz : aaa : rid of `#[ cfg( not( feature = "use_alloc" ) ) ]` -- Rid of by not relying on std
-// #[ cfg( not( feature = "use_alloc" ) ) ]
 #[ cfg( all( feature = "enabled", feature = "collection_constructors" ) ) ]
-#[ cfg( any( not( feature = "no_std" ), feature = "use_alloc" ) ) ]
+#[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
 fn main()
 {
   use collection_tools::*;
diff --git a/module/core/collection_tools/src/collection.rs b/module/core/collection_tools/src/collection.rs
deleted file mode 100644
index 67315f35a4..0000000000
--- a/module/core/collection_tools/src/collection.rs
+++ /dev/null
@@ -1,32 +0,0 @@
-/// Not meant to be called directly.
-#[ doc( hidden ) ]
-#[ macro_export( local_inner_macros ) ]
-macro_rules! count
-{
-  ( @single $( $x : tt )* ) => ( () );
-
-  (
-    @count $( $rest : expr ),*
-  )
-  =>
-  (
-    < [ () ] >::len( &[ $( count!( @single $rest ) ),* ] )
-  );
-}
-
-/// [std::collections::BTreeMap] macros
-pub mod bmap;
-/// [std::collections::BTreeSet] macros
-pub mod bset;
-/// [std::collections::BinaryHeap] macros
-pub mod heap;
-/// [std::collections::HashMap] macros
-pub mod hmap;
-/// [std::collections::HashSet] macros
-pub mod hset;
-/// [std::collections::LinkedList] macros
-pub mod llist;
-/// [Vec] macros
-pub mod vec;
-/// [std::collections::VecDeque] macros
-pub mod deque;
diff --git a/module/core/collection_tools/src/collection/heap.rs b/module/core/collection_tools/src/collection/binary_heap.rs
similarity index 95%
rename from module/core/collection_tools/src/collection/heap.rs
rename to module/core/collection_tools/src/collection/binary_heap.rs
index 8d38492497..965f5804c5 100644
--- a/module/core/collection_tools/src/collection/heap.rs
+++ b/module/core/collection_tools/src/collection/binary_heap.rs
@@ -1,6 +1,9 @@
+#[ allow( unused_imports ) ]
+use super::*;
+
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
- pub use alloc::collections::binary_heap::*;
+pub use alloc::collections::binary_heap::*;
 
 /// Creates a `BinaryHeap` from a list of elements.
 ///
@@ -57,7 +60,7 @@ macro_rules! heap
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _heap = $crate::heap::BinaryHeap::with_capacity( _cap );
+    let mut _heap = $crate::collection::BinaryHeap::with_capacity( _cap );
     $(
       _heap.push( $key );
     )*
@@ -146,7 +149,7 @@ macro_rules! into_heap
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _heap = $crate::heap::BinaryHeap::with_capacity( _cap );
+    let mut _heap = $crate::collection::BinaryHeap::with_capacity( _cap );
     $(
       _heap.push( Into::into( $key ) );
     )*
diff --git a/module/core/collection_tools/src/collection/bmap.rs b/module/core/collection_tools/src/collection/btree_map.rs
similarity index 97%
rename from module/core/collection_tools/src/collection/bmap.rs
rename to module/core/collection_tools/src/collection/btree_map.rs
index e96f045e84..2e4ec94f13 100644
--- a/module/core/collection_tools/src/collection/bmap.rs
+++ b/module/core/collection_tools/src/collection/btree_map.rs
@@ -1,3 +1,6 @@
+#[ allow( unused_imports ) ]
+use super::*;
+
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use alloc::collections::btree_map::*;
@@ -70,7 +73,7 @@ macro_rules! bmap
   )
   =>
   {{
-    let mut _map = $crate::bmap::BTreeMap::new();
+    let mut _map = $crate::collection::BTreeMap::new();
     $(
       let _ = _map.insert( $key , $value );
     )*
@@ -163,7 +166,7 @@ macro_rules! into_bmap
   )
   =>
   {{
-    let mut _map = $crate::bmap::BTreeMap::new();
+    let mut _map = $crate::collection::BTreeMap::new();
     $(
       let _ = _map.insert( Into::into( $key ), Into::into( $value ) );
     )*
diff --git a/module/core/collection_tools/src/collection/bset.rs b/module/core/collection_tools/src/collection/btree_set.rs
similarity index 96%
rename from module/core/collection_tools/src/collection/bset.rs
rename to module/core/collection_tools/src/collection/btree_set.rs
index c0c6d249ed..7111811c2e 100644
--- a/module/core/collection_tools/src/collection/bset.rs
+++ b/module/core/collection_tools/src/collection/btree_set.rs
@@ -1,3 +1,6 @@
+#[ allow( unused_imports ) ]
+use super::*;
+
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use alloc::collections::btree_set::*;
@@ -56,7 +59,7 @@ macro_rules! bset
   )
   =>
   {{
-    let mut _set = $crate::bset::BTreeSet::new();
+    let mut _set = $crate::collection::BTreeSet::new();
     $(
       _set.insert( $key );
     )*
@@ -149,7 +152,7 @@ macro_rules! into_bset
   )
   =>
   {{
-    let mut _set = $crate::bset::BTreeSet::new();
+    let mut _set = $crate::collection::BTreeSet::new();
     $(
       _set.insert( Into::into( $key ) );
     )*
diff --git a/module/core/collection_tools/src/collection/hmap.rs b/module/core/collection_tools/src/collection/hash_map.rs
similarity index 93%
rename from module/core/collection_tools/src/collection/hmap.rs
rename to module/core/collection_tools/src/collection/hash_map.rs
index eceac4ee9b..8ebbc9f90f 100644
--- a/module/core/collection_tools/src/collection/hmap.rs
+++ b/module/core/collection_tools/src/collection/hash_map.rs
@@ -1,7 +1,12 @@
-#[ cfg( feature = "use_alloc" ) ]
+#[ allow( unused_imports ) ]
+use super::*;
+
+// xxx : qqq : wrong
+#[ cfg( all( feature = "no_std", feature = "use_alloc" ) ) ]
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use crate::dependency::hashbrown::hash_map::*;
+
 #[ cfg( not( feature = "no_std" ) ) ]
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
@@ -14,7 +19,7 @@ pub use std::collections::hash_map::*;
 /// # Origin
 ///
 /// This collection can be reexported from different crates:
-/// - from `std`, if `no_std` flag if off
+/// - from `std`, if `use_std` is on ( `no_std` flag if off )
 /// - from `hashbrown`, if `use_alloc` flag if on
 ///
 /// # Syntax
@@ -77,7 +82,7 @@ macro_rules! hmap
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _map = $crate::hmap::HashMap::with_capacity( _cap );
+    let mut _map = $crate::collection::HashMap::with_capacity( _cap );
     $(
       let _ = _map.insert( $key, $value );
     )*
@@ -98,7 +103,7 @@ macro_rules! hmap
 /// # Origin
 ///
 /// This collection can be reexported from different crates:
-/// - from `std`, if `no_std` flag if off
+/// - from `std`, if `use_std` is on ( `no_std` flag if off )
 /// - from `hashbrown`, if `use_alloc` flag if on
 ///
 /// # Syntax
@@ -172,7 +177,7 @@ macro_rules! into_hmap
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _map = $crate::hmap::HashMap::with_capacity( _cap );
+    let mut _map = $crate::collection::HashMap::with_capacity( _cap );
     $(
       let _ = _map.insert( Into::into( $key ), Into::into( $value ) );
     )*
diff --git a/module/core/collection_tools/src/collection/hset.rs b/module/core/collection_tools/src/collection/hash_set.rs
similarity index 94%
rename from module/core/collection_tools/src/collection/hset.rs
rename to module/core/collection_tools/src/collection/hash_set.rs
index b9b2d682da..6fe8d8287a 100644
--- a/module/core/collection_tools/src/collection/hset.rs
+++ b/module/core/collection_tools/src/collection/hash_set.rs
@@ -1,7 +1,11 @@
+#[ allow( unused_imports ) ]
+use super::*;
+
 #[ cfg( feature = "use_alloc" ) ]
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use crate::dependency::hashbrown::hash_set::*;
+
 #[ cfg( not( feature = "no_std" ) ) ]
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
@@ -14,7 +18,7 @@ pub use std::collections::hash_set::*;
 /// # Origin
 ///
 /// This collection can be reexported from different crates:
-/// - from `std`, if `no_std` flag if off
+/// - from `std`, if `use_std` is on ( `no_std` flag if off )
 /// - from `hashbrown`, if `use_alloc` flag if on
 ///
 /// # Syntax
@@ -77,7 +81,7 @@ macro_rules! hset
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _set = $crate::hset::HashSet::with_capacity( _cap );
+    let mut _set = $crate::collection::HashSet::with_capacity( _cap );
     $(
       let _ = _set.insert( $key );
     )*
@@ -96,9 +100,9 @@ macro_rules! hset
 /// type `T` used in the `HashSet`. Also, this means that sometimes you must specify the type of collection's items.
 ///
 /// # Origin
-/// 
+///
 /// This collection can be reexported from different crates:
-/// - from `std`, if `no_std` flag if off
+/// - from `std`, if `use_std` is on ( `no_std` flag if off )
 /// - from `hashbrown`, if `use_alloc` flag if on
 ///
 /// # Syntax
@@ -173,7 +177,7 @@ macro_rules! into_hset
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _set = $crate::hset::HashSet::with_capacity( _cap );
+    let mut _set = $crate::collection::HashSet::with_capacity( _cap );
     $(
       let _ = _set.insert( Into::into( $key ) );
     )*
diff --git a/module/core/collection_tools/src/collection/llist.rs b/module/core/collection_tools/src/collection/linked_list.rs
similarity index 97%
rename from module/core/collection_tools/src/collection/llist.rs
rename to module/core/collection_tools/src/collection/linked_list.rs
index e6c8ddbe68..cc23637be1 100644
--- a/module/core/collection_tools/src/collection/llist.rs
+++ b/module/core/collection_tools/src/collection/linked_list.rs
@@ -1,3 +1,6 @@
+#[ allow( unused_imports ) ]
+use super::*;
+
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use alloc::collections::linked_list::*;
@@ -70,7 +73,7 @@ macro_rules! llist
   {{
     // "The LinkedList allows pushing and popping elements at either end in constant time."
     // So no `with_capacity`
-    let mut _lst = $crate::llist::LinkedList::new();
+    let mut _lst = $crate::collection::LinkedList::new();
     $(
       _lst.push_back( $key );
     )*
@@ -164,7 +167,7 @@ macro_rules! into_llist
   {{
     // "The LinkedList allows pushing and popping elements at either end in constant time."
     // So no `with_capacity`
-    let mut _lst = $crate::llist::LinkedList::new();
+    let mut _lst = $crate::collection::LinkedList::new();
     $(
       _lst.push_back( Into::into( $key ) );
     )*
diff --git a/module/core/collection_tools/src/collection/mod.rs b/module/core/collection_tools/src/collection/mod.rs
new file mode 100644
index 0000000000..0f74158835
--- /dev/null
+++ b/module/core/collection_tools/src/collection/mod.rs
@@ -0,0 +1,160 @@
+/// Not meant to be called directly.
+#[ doc( hidden ) ]
+#[ macro_export( local_inner_macros ) ]
+macro_rules! count
+{
+  ( @single $( $x : tt )* ) => ( () );
+
+  (
+    @count $( $rest : expr ),*
+  )
+  =>
+  (
+    < [ () ] >::len( &[ $( count!( @single $rest ) ),* ] )
+  );
+}
+
+#[ cfg( feature = "enabled" ) ]
+#[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+extern crate alloc;
+
+/// [std::collections::BTreeMap] macros
+pub mod btree_map;
+/// [std::collections::BTreeSet] macros
+pub mod btree_set;
+/// [std::collections::BinaryHeap] macros
+pub mod binary_heap;
+/// [std::collections::HashMap] macros
+pub mod hash_map;
+/// [std::collections::HashSet] macros
+pub mod hash_set;
+/// [std::collections::LinkedList] macros
+pub mod linked_list;
+/// [Vec] macros
+pub mod vector;
+/// [std::collections::VecDeque] macros
+pub mod vec_deque;
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+#[ cfg( feature = "enabled" ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod own
+{
+  use super::*;
+
+  pub use super::
+  {
+    btree_map,
+    btree_set,
+    binary_heap,
+    hash_map,
+    hash_set,
+    linked_list,
+    vector,
+    vec_deque,
+  };
+
+  #[ doc( inline ) ]
+  pub use orphan::*;
+
+}
+
+/// Parented namespace of the module.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+  #[ doc( inline ) ]
+  pub use exposed::*;
+}
+
+/// Exposed namespace of the module.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
+
+  #[ doc( inline ) ]
+  pub use super::super::collection;
+
+  #[ doc( inline ) ]
+  #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+  #[ cfg( feature = "collection_constructors" ) ]
+  pub use crate::
+  {
+    vec as dlist,
+    deque,
+    llist,
+    hset,
+    hmap,
+    bmap,
+    bset,
+  };
+
+  #[ doc( inline ) ]
+  #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+  #[ cfg( feature = "collection_into_constructors" ) ]
+  pub use crate::
+  {
+    into_vec,
+    into_vec as into_dlist,
+    into_vecd,
+    into_llist,
+    into_hset,
+    into_hmap,
+    into_bmap,
+    into_bset,
+  };
+
+  // #[ cfg( feature = "reexports" ) ]
+  #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+  #[ doc( inline ) ]
+  pub use
+  {
+    btree_map::BTreeMap,
+    btree_set::BTreeSet,
+    binary_heap::BinaryHeap,
+    hash_map::HashMap,
+    hash_set::HashSet,
+    linked_list::LinkedList,
+    vector::Vec,
+    vec_deque::VecDeque,
+  };
+
+  // #[ cfg( feature = "reexports" ) ]
+  #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+  #[ doc( inline ) ]
+  pub use
+  {
+    LinkedList as Llist,
+    Vec as Dlist,
+    VecDeque as Deque,
+    HashMap as Map,
+    HashMap as Hmap,
+    HashSet as Set,
+    HashSet as Hset,
+    BTreeMap as Bmap,
+    BTreeSet as Bset,
+  };
+
+  // qqq : cover by tests presence of all containers immidiately in collection_tools::* and in collection_tools::exposed::*
+
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+}
diff --git a/module/core/collection_tools/src/collection/deque.rs b/module/core/collection_tools/src/collection/vec_deque.rs
similarity index 96%
rename from module/core/collection_tools/src/collection/deque.rs
rename to module/core/collection_tools/src/collection/vec_deque.rs
index 66b106c6ec..1060d01c0b 100644
--- a/module/core/collection_tools/src/collection/deque.rs
+++ b/module/core/collection_tools/src/collection/vec_deque.rs
@@ -1,3 +1,6 @@
+#[ allow( unused_imports ) ]
+use super::*;
+
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use alloc::collections::vec_deque::*;
@@ -75,7 +78,7 @@ macro_rules! deque
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _vecd = $crate::deque::VecDeque::with_capacity( _cap );
+    let mut _vecd = $crate::collection::VecDeque::with_capacity( _cap );
     $(
       _vecd.push_back( $key );
     )*
@@ -168,7 +171,7 @@ macro_rules! into_vecd
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _vecd = $crate::deque::VecDeque::with_capacity( _cap );
+    let mut _vecd = $crate::collection::VecDeque::with_capacity( _cap );
     $(
       _vecd.push_back( Into::into( $key ) );
     )*
diff --git a/module/core/collection_tools/src/collection/vec.rs b/module/core/collection_tools/src/collection/vector.rs
similarity index 96%
rename from module/core/collection_tools/src/collection/vec.rs
rename to module/core/collection_tools/src/collection/vector.rs
index 2c19db388f..0ae9ccf6dd 100644
--- a/module/core/collection_tools/src/collection/vec.rs
+++ b/module/core/collection_tools/src/collection/vector.rs
@@ -1,6 +1,10 @@
+#[ allow( unused_imports ) ]
+use super::*;
+
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use alloc::vec::*;
+
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use core::slice::{ Iter, IterMut };
@@ -73,7 +77,7 @@ macro_rules! vec
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _vec = $crate::vec::Vec::with_capacity( _cap );
+    let mut _vec = $crate::collection::Vec::with_capacity( _cap );
     $(
       _vec.push( $key );
     )*
@@ -167,7 +171,7 @@ macro_rules! into_vec
   =>
   {{
     let _cap = count!( @count $( $key ),* );
-    let mut _vec = $crate::vec::Vec::with_capacity( _cap );
+    let mut _vec = $crate::collection::Vec::with_capacity( _cap );
     $(
       _vec.push( Into::into( $key ) );
     )*
diff --git a/module/core/collection_tools/src/lib.rs b/module/core/collection_tools/src/lib.rs
index e447f16f85..bcbbb4bdbc 100644
--- a/module/core/collection_tools/src/lib.rs
+++ b/module/core/collection_tools/src/lib.rs
@@ -4,17 +4,18 @@
 #![ doc( html_root_url = "https://docs.rs/collection_tools/latest/collection_tools/" ) ]
 #![ doc = include_str!( concat!( env!( "CARGO_MANIFEST_DIR" ), "/", "Readme.md" ) ) ]
 
-#[ cfg( feature = "enabled" ) ]
-#[ cfg( any( not( feature = "no_std" ), feature = "use_alloc" ) ) ]
-extern crate alloc;
+// #[ cfg( feature = "enabled" ) ]
+// #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+// extern crate alloc;
 
 /// Module containing all collection macros
 #[ cfg( feature = "enabled" ) ]
-#[ cfg( any( not( feature = "no_std" ), feature = "use_alloc" ) ) ]
-mod collection;
-#[ cfg( feature = "enabled" ) ]
-#[ cfg( any( not( feature = "no_std" ), feature = "use_alloc" ) ) ]
-pub use collection::*;
+#[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+pub mod collection;
+
+// #[ cfg( feature = "enabled" ) ]
+// #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
+// pub use collection::*;
 
 /// Namespace with dependencies.
 #[ cfg( feature = "enabled" ) ]
@@ -36,10 +37,13 @@ pub use own::*;
 #[ allow( unused_imports ) ]
 pub mod own
 {
-  use super::*;
+  // use super::*;
 
   #[ doc( inline ) ]
-  pub use orphan::*;
+  pub use super::orphan::*;
+
+  #[ doc( inline ) ]
+  pub use super::collection::own::*;
 
 }
 
@@ -51,6 +55,10 @@ pub mod orphan
   use super::*;
   #[ doc( inline ) ]
   pub use exposed::*;
+
+  #[ doc( inline ) ]
+  pub use collection::orphan::*;
+
 }
 
 /// Exposed namespace of the module.
@@ -64,66 +72,7 @@ pub mod exposed
   pub use prelude::*;
 
   #[ doc( inline ) ]
-  #[ cfg( any( feature = "use_alloc", all( feature = "collection_constructors", not( feature = "no_std" ) ) ) ) ]
-  pub use crate::
-  {
-    vec as dlist,
-    deque,
-    llist,
-    hset,
-    hmap,
-    bmap,
-    bset,
-  };
-
-  #[ doc( inline ) ]
-  #[ cfg( any( feature = "use_alloc", all( feature = "collection_into_constructors", not( feature = "no_std" ) ) ) ) ]
-  pub use crate::
-  {
-    into_vec,
-    into_vec as into_dlist,
-    into_vecd,
-    into_llist,
-    into_hset,
-    into_hmap,
-    into_bmap,
-    into_bset,
-  };
-
-  // #[ cfg( feature = "reexports" ) ]
-  #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use crate::
-  {
-    bmap::BTreeMap,
-    bset::BTreeSet,
-    heap::BinaryHeap,
-    hmap::HashMap,
-    hset::HashSet,
-    llist::LinkedList,
-    vec::Vec,
-    deque::VecDeque,
-  };
-
-  // #[ cfg( feature = "reexports" ) ]
-  #[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use
-  {
-    LinkedList as Llist,
-    Vec as Dlist,
-    VecDeque as Deque,
-    HashMap as Map,
-    HashMap as Hmap,
-    HashSet as Set,
-    HashSet as Hset,
-    BTreeMap as Bmap,
-    BTreeSet as Bset,
-  };
-
-  // qqq : cover by tests presence of all containers immidiately in collection_tools::* and in collection_tools::exposed::*
+  pub use collection::exposed::*;
 
 }
 
@@ -133,4 +82,16 @@ pub mod exposed
 pub mod prelude
 {
   use super::*;
+
+  #[ doc( inline ) ]
+  pub use collection::prelude::*;
+
 }
+
+// pub use own::collection as xxx;
+// pub use hmap as xxx;
+// pub use own::HashMap as xxx;
+// pub fn x()
+// {
+//   let x : HashMap< usize, usize > = hmap!{};
+// }
diff --git a/module/core/collection_tools/tests/inc/bmap.rs b/module/core/collection_tools/tests/inc/bmap.rs
index af3d54dae5..113e69f810 100644
--- a/module/core/collection_tools/tests/inc/bmap.rs
+++ b/module/core/collection_tools/tests/inc/bmap.rs
@@ -68,7 +68,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = ( i32, i32 );
-    type IntoIter = the_module::bmap::IntoIter< i32, i32 >;
+    type IntoIter = the_module::btree_map::IntoIter< i32, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -79,7 +79,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = ( &'a i32, &'a i32 );
-    type IntoIter = the_module::bmap::Iter< 'a, i32, i32 >;
+    type IntoIter = the_module::btree_map::Iter< 'a, i32, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/inc/bset.rs b/module/core/collection_tools/tests/inc/bset.rs
index 2a427d0a26..9fb625bf30 100644
--- a/module/core/collection_tools/tests/inc/bset.rs
+++ b/module/core/collection_tools/tests/inc/bset.rs
@@ -67,7 +67,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = i32;
-    type IntoIter = the_module::bset::IntoIter< i32 >;
+    type IntoIter = the_module::btree_set::IntoIter< i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -78,7 +78,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = &'a i32;
-    type IntoIter = the_module::bset::Iter< 'a, i32 >;
+    type IntoIter = the_module::btree_set::Iter< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/inc/deque.rs b/module/core/collection_tools/tests/inc/deque.rs
index 98ab6498bd..d58c72d8cc 100644
--- a/module/core/collection_tools/tests/inc/deque.rs
+++ b/module/core/collection_tools/tests/inc/deque.rs
@@ -66,7 +66,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = i32;
-    type IntoIter = the_module::deque::IntoIter< i32 >;
+    type IntoIter = the_module::vec_deque::IntoIter< i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -77,7 +77,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = &'a i32;
-    type IntoIter = the_module::deque::Iter< 'a, i32 >;
+    type IntoIter = the_module::vec_deque::Iter< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -88,7 +88,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a mut MyContainer
   {
     type Item = &'a mut i32;
-    type IntoIter = the_module::deque::IterMut< 'a, i32 >;
+    type IntoIter = the_module::vec_deque::IterMut< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/inc/heap.rs b/module/core/collection_tools/tests/inc/heap.rs
index a342548cfc..ad251e0b39 100644
--- a/module/core/collection_tools/tests/inc/heap.rs
+++ b/module/core/collection_tools/tests/inc/heap.rs
@@ -62,7 +62,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = i32;
-    type IntoIter = the_module::heap::IntoIter< i32 >;
+    type IntoIter = the_module::binary_heap::IntoIter< i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -73,7 +73,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = &'a i32;
-    type IntoIter = the_module::heap::Iter< 'a, i32 >;
+    type IntoIter = the_module::binary_heap::Iter< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/inc/hmap.rs b/module/core/collection_tools/tests/inc/hmap.rs
index 629c7155a6..042b4c8653 100644
--- a/module/core/collection_tools/tests/inc/hmap.rs
+++ b/module/core/collection_tools/tests/inc/hmap.rs
@@ -77,7 +77,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = ( i32, i32 );
-    type IntoIter = the_module::hmap::IntoIter< i32, i32 >;
+    type IntoIter = the_module::hash_map::IntoIter< i32, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -88,7 +88,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = ( &'a i32, &'a i32 );
-    type IntoIter = the_module::hmap::Iter< 'a, i32, i32 >;
+    type IntoIter = the_module::hash_map::Iter< 'a, i32, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -99,7 +99,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a mut MyContainer
   {
     type Item = ( &'a i32, &'a mut i32 );
-    type IntoIter = the_module::hmap::IterMut< 'a, i32, i32 >;
+    type IntoIter = the_module::hash_map::IterMut< 'a, i32, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/inc/hset.rs b/module/core/collection_tools/tests/inc/hset.rs
index c844836874..b3af31cb2d 100644
--- a/module/core/collection_tools/tests/inc/hset.rs
+++ b/module/core/collection_tools/tests/inc/hset.rs
@@ -74,7 +74,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = i32;
-    type IntoIter = the_module::hset::IntoIter< i32 >;
+    type IntoIter = the_module::hash_set::IntoIter< i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -85,7 +85,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = &'a i32;
-    type IntoIter = the_module::hset::Iter< 'a, i32 >;
+    type IntoIter = the_module::hash_set::Iter< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/inc/llist.rs b/module/core/collection_tools/tests/inc/llist.rs
index 68620e2a69..3a861b0ec2 100644
--- a/module/core/collection_tools/tests/inc/llist.rs
+++ b/module/core/collection_tools/tests/inc/llist.rs
@@ -67,7 +67,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = i32;
-    type IntoIter = the_module::llist::IntoIter< i32 >;
+    type IntoIter = the_module::linked_list::IntoIter< i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -78,7 +78,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = &'a i32;
-    type IntoIter = the_module::llist::Iter< 'a, i32 >;
+    type IntoIter = the_module::linked_list::Iter< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -89,7 +89,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a mut MyContainer
   {
     type Item = &'a mut i32;
-    type IntoIter = the_module::llist::IterMut< 'a, i32 >;
+    type IntoIter = the_module::linked_list::IterMut< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/inc/mod.rs b/module/core/collection_tools/tests/inc/mod.rs
index ddd10e261d..86855a9d84 100644
--- a/module/core/collection_tools/tests/inc/mod.rs
+++ b/module/core/collection_tools/tests/inc/mod.rs
@@ -9,6 +9,7 @@ mod llist;
 mod vec;
 mod deque;
 
+mod namespace_test;
 mod components;
 
 // qqq : make subdirectory for each container -- done
diff --git a/module/core/collection_tools/tests/inc/namespace_test.rs b/module/core/collection_tools/tests/inc/namespace_test.rs
new file mode 100644
index 0000000000..841ecac64f
--- /dev/null
+++ b/module/core/collection_tools/tests/inc/namespace_test.rs
@@ -0,0 +1,12 @@
+use super::*;
+
+#[ test ]
+fn exposed_main_namespace()
+{
+
+  let _v : Vec< u32 > = the_module::collection::Vec::new();
+  let _v : Vec< u32 > = the_module::exposed::collection::Vec::new();
+  use the_module::exposed::*;
+  let _v : Vec< u32 > = collection::Vec::new();
+
+}
\ No newline at end of file
diff --git a/module/core/collection_tools/tests/inc/vec.rs b/module/core/collection_tools/tests/inc/vec.rs
index c1a5f66804..5bf78631ba 100644
--- a/module/core/collection_tools/tests/inc/vec.rs
+++ b/module/core/collection_tools/tests/inc/vec.rs
@@ -1,7 +1,7 @@
 use super::*;
 
 #[ test ]
-#[ cfg( any( not( feature = "no_std" ), feature = "use_alloc" ) ) ]
+#[ cfg( any( feature = "use_alloc", not( feature = "no_std" ) ) ) ]
 fn reexport()
 {
 
@@ -86,7 +86,7 @@ fn iters()
   impl IntoIterator for MyContainer
   {
     type Item = i32;
-    type IntoIter = the_module::vec::IntoIter< i32 >;
+    type IntoIter = the_module::vector::IntoIter< i32 >;
     // qqq : should work -- works
 
     fn into_iter( self ) -> Self::IntoIter
@@ -98,7 +98,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a MyContainer
   {
     type Item = &'a i32;
-    type IntoIter = the_module::vec::Iter< 'a, i32 >;
+    type IntoIter = the_module::vector::Iter< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
@@ -109,7 +109,7 @@ fn iters()
   impl< 'a > IntoIterator for &'a mut MyContainer
   {
     type Item = &'a mut i32;
-    type IntoIter = the_module::vec::IterMut< 'a, i32 >;
+    type IntoIter = the_module::vector::IterMut< 'a, i32 >;
 
     fn into_iter( self ) -> Self::IntoIter
     {
diff --git a/module/core/collection_tools/tests/tests.rs b/module/core/collection_tools/tests/tests.rs
index a36c5debec..ecc936c445 100644
--- a/module/core/collection_tools/tests/tests.rs
+++ b/module/core/collection_tools/tests/tests.rs
@@ -1,4 +1,4 @@
-// usual tests
+#![ allow( unused_imports ) ]
 
 #[ path="../../../../module/step/meta/src/module/aggregating.rs" ]
 mod aggregating;
diff --git a/module/core/error_tools/Cargo.toml b/module/core/error_tools/Cargo.toml
index de02c81004..dafae99166 100644
--- a/module/core/error_tools/Cargo.toml
+++ b/module/core/error_tools/Cargo.toml
@@ -48,8 +48,9 @@ error_untyped = [ "anyhow" ]
 # = entry
 
 [dependencies]
-anyhow = { version = "~1.0", optional = true }
-thiserror = { version = "~1.0", optional = true }
+anyhow = { workspace = true, optional = true }
+thiserror = { workspace = true, optional = true }
 
 [dev-dependencies]
 test_tools = { workspace = true }
+# xxx : qqq : review
\ No newline at end of file
diff --git a/module/core/error_tools/examples/error_tools_trivial.rs b/module/core/error_tools/examples/error_tools_trivial.rs
index cc6fc29f24..e6ddd65432 100644
--- a/module/core/error_tools/examples/error_tools_trivial.rs
+++ b/module/core/error_tools/examples/error_tools_trivial.rs
@@ -17,5 +17,5 @@ fn main()
 fn f1() -> error_tools::untyped::Result< () >
 {
   let _read = std::fs::read_to_string( "Cargo.toml" )?;
-  Err( error_tools::BasicError::new( "Some error" ).into() )
+  Err( error_tools::untyped::format_err!( "Some error" ) )
 }
diff --git a/module/core/error_tools/src/assert.rs b/module/core/error_tools/src/error/assert.rs
similarity index 100%
rename from module/core/error_tools/src/assert.rs
rename to module/core/error_tools/src/error/assert.rs
diff --git a/module/core/error_tools/src/error.rs b/module/core/error_tools/src/error/mod.rs
similarity index 54%
rename from module/core/error_tools/src/error.rs
rename to module/core/error_tools/src/error/mod.rs
index 730f9c477c..cd999e016d 100644
--- a/module/core/error_tools/src/error.rs
+++ b/module/core/error_tools/src/error/mod.rs
@@ -96,132 +96,178 @@ mod private
   /// helps in defining such results more concisely.
   pub type ResultWithReport< Report, Error > = Result< Report, ( Report, Error ) >;
 
-  ///
-  /// Macro to generate an error descriptor.
-  ///
-  /// ### Basic use-case.
-  /// ```rust
-  /// # use error_tools::{ BasicError, err };
-  /// fn f1() -> BasicError
-  /// {
-  ///   return err!( "No attr" );
-  /// }
-  /// ```
-  ///
-
-  #[ macro_export ]
-  macro_rules! err
-  {
-
-    ( $msg : expr ) =>
-    {
-      $crate::BasicError::new( $msg ).into()
-    };
-    ( $msg : expr, $( $arg : expr ),+ $(,)? ) =>
-    {
-      $crate::BasicError::new( format!( $msg, $( $arg ),+ ) ).into()
-    };
-
-  }
-
-  ///
-  /// Macro to return an Err( error ) generating error descriptor.
-  ///
-  /// ### Basic use-case.
-  /// ```rust
-  /// # use error_tools::{ BasicError, return_err };
-  /// fn f1() -> Result< (), BasicError >
-  /// {
-  ///   return_err!( "No attr" );
-  /// }
-  /// ```
-  ///
-
-  #[ macro_export ]
-  macro_rules! return_err
-  {
-
-    ( $msg : expr ) =>
-    {
-      return Result::Err( $crate::err!( $msg ) )
-    };
-    ( $msg : expr, $( $arg : expr ),+ $(,)? ) =>
-    {
-      return Result::Err( $crate::err!( $msg, $( $arg ),+ ) )
-    };
-
-  }
-
-  // zzz : review
-
-  /// baic implementation of generic BasicError
-
-  #[ derive( core::fmt::Debug, core::clone::Clone, core::cmp::PartialEq, core::cmp::Eq ) ]
-  pub struct BasicError
-  {
-    msg : String,
-  }
-
-  impl BasicError
-  {
-    /// Constructor expecting message with description.
-    pub fn new< Msg : Into< String > >( msg : Msg ) -> BasicError
-    {
-      BasicError { msg : msg.into() }
-    }
-    /// Message with description getter.
-    pub fn msg( &self ) -> &String
-    {
-      &self.msg
-    }
-  }
+//   ///
+//   /// Macro to generate an error descriptor.
+//   ///
+//   /// ### Basic use-case.
+//   /// ```rust
+//   /// # use error_tools::{ BasicError, err };
+//   /// fn f1() -> BasicError
+//   /// {
+//   ///   return err!( "No attr" );
+//   /// }
+//   /// ```
+//   ///
+//
+//   #[ macro_export ]
+//   macro_rules! err
+//   {
+//
+//     ( $msg : expr ) =>
+//     {
+//       $crate::BasicError::new( $msg ).into()
+//     };
+//     ( $msg : expr, $( $arg : expr ),+ $(,)? ) =>
+//     {
+//       $crate::BasicError::new( format!( $msg, $( $arg ),+ ) ).into()
+//     };
+//
+//   }
+//
+//   ///
+//   /// Macro to return an Err( error ) generating error descriptor.
+//   ///
+//   /// ### Basic use-case.
+//   /// ```rust
+//   /// # use error_tools::{ BasicError, return_err };
+//   /// fn f1() -> Result< (), BasicError >
+//   /// {
+//   ///   return_err!( "No attr" );
+//   /// }
+//   /// ```
+//   ///
+//
+//   #[ macro_export ]
+//   macro_rules! return_err
+//   {
+//
+//     ( $msg : expr ) =>
+//     {
+//       return Result::Err( $crate::err!( $msg ) )
+//     };
+//     ( $msg : expr, $( $arg : expr ),+ $(,)? ) =>
+//     {
+//       return Result::Err( $crate::err!( $msg, $( $arg ),+ ) )
+//     };
+//
+//   }
+//
+//   // zzz : review
+//   // xxx : rid of
+//
+//   /// baic implementation of generic BasicError
+//
+//   #[ derive( core::fmt::Debug, core::clone::Clone, core::cmp::PartialEq, core::cmp::Eq ) ]
+//   pub struct BasicError
+//   {
+//     msg : String,
+//   }
+//
+//   impl BasicError
+//   {
+//     /// Constructor expecting message with description.
+//     pub fn new< Msg : Into< String > >( msg : Msg ) -> BasicError
+//     {
+//       BasicError { msg : msg.into() }
+//     }
+//     /// Message with description getter.
+//     pub fn msg( &self ) -> &String
+//     {
+//       &self.msg
+//     }
+//   }
+//
+//   impl core::fmt::Display for BasicError
+//   {
+//     fn fmt(&self, f: &mut core::fmt::Formatter< '_ >) -> core::fmt::Result
+//     {
+//       write!( f, "{}", self.msg )
+//     }
+//   }
+//
+//   impl ErrorTrait for BasicError
+//   {
+//     fn description( &self ) -> &str
+//     {
+//       &self.msg
+//     }
+//   }
+//
+//   impl< T > From< BasicError > for Result< T, BasicError >
+//   {
+//     /// Returns the argument unchanged.
+//     #[ inline( always ) ]
+//     fn from( src : BasicError ) -> Self
+//     {
+//       Result::Err( src )
+//     }
+//   }
+//
+//   pub use err;
+//   pub use return_err;
 
-  impl core::fmt::Display for BasicError
-  {
-    fn fmt(&self, f: &mut core::fmt::Formatter< '_ >) -> core::fmt::Result
-    {
-      write!( f, "{}", self.msg )
-    }
-  }
-
-  impl ErrorTrait for BasicError
-  {
-    fn description( &self ) -> &str
-    {
-      &self.msg
-    }
-  }
+  // qqq : write standard mod interface without using mod_interface /* aaa : Dmytro : added to each library file */
+}
 
-  impl< T > From< BasicError > for Result< T, BasicError >
-  {
-    /// Returns the argument unchanged.
-    #[ inline( always ) ]
-    fn from( src : BasicError ) -> Self
-    {
-      Result::Err( src )
-    }
-  }
+/// Assertions.
+#[ cfg( feature = "enabled" ) ]
+pub mod assert;
 
-  pub use err;
-  pub use return_err;
+#[ cfg( feature = "enabled" ) ]
+#[ cfg( feature = "error_typed" ) ]
+/// Typed exceptions handling mechanism.
+pub mod typed;
 
-  // qqq : write standard mod interface without using mod_interface /* aaa : Dmytro : added to each library file */
-}
+#[ cfg( feature = "enabled" ) ]
+#[ cfg( feature = "error_untyped" ) ]
+/// Untyped exceptions handling mechanism.
+pub mod untyped;
 
+#[ cfg( feature = "enabled" ) ]
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
 pub use own::*;
 
 /// Own namespace of the module.
+#[ cfg( feature = "enabled" ) ]
 #[ allow( unused_imports ) ]
 pub mod own
 {
   use super::*;
+
   #[ doc( inline ) ]
   pub use orphan::*;
+
+  #[ doc( inline ) ]
+  pub use assert::orphan::*;
+
+  #[ cfg( feature = "error_untyped" ) ]
+  #[ doc( inline ) ]
+  pub use untyped::orphan::*;
+
+  #[ cfg( feature = "error_typed" ) ]
+  #[ doc( inline ) ]
+  pub use typed::orphan::*;
+
+  #[ doc( inline ) ]
+  pub use private::
+  {
+    // err,
+    // return_err,
+    ErrorTrait,
+    // BasicError,
+  };
+
+  pub use super::assert;
+  #[ cfg( feature = "error_typed" ) ]
+  pub use super::typed;
+  #[ cfg( feature = "error_untyped" ) ]
+  pub use super::untyped;
+
 }
 
 /// Shared with parent namespace of the module
+#[ cfg( feature = "enabled" ) ]
 #[ allow( unused_imports ) ]
 pub mod orphan
 {
@@ -231,11 +277,18 @@ pub mod orphan
 }
 
 /// Exposed namespace of the module.
+#[ cfg( feature = "enabled" ) ]
 #[ allow( unused_imports ) ]
 pub mod exposed
 {
   use super::*;
 
+  #[ doc( inline ) ]
+  pub use prelude::*;
+
+  // Expose itself.
+  pub use super::super::error;
+
   #[ doc( inline ) ]
   pub use private::
   {
@@ -244,22 +297,43 @@ pub mod exposed
   };
 
   #[ doc( inline ) ]
-  pub use prelude::*;
+  pub use assert::exposed::*;
+
+  #[ cfg( feature = "error_untyped" ) ]
+  #[ doc( inline ) ]
+  pub use untyped::exposed::*;
+
+  #[ cfg( feature = "error_typed" ) ]
+  #[ doc( inline ) ]
+  pub use typed::exposed::*;
+
 }
 
 /// Prelude to use essentials: `use my_module::prelude::*`.
+#[ cfg( feature = "enabled" ) ]
 #[ allow( unused_imports ) ]
 pub mod prelude
 {
   use super::*;
 
+  // #[ doc( inline ) ]
+  // pub use private::
+  // {
+  //   // err,
+  //   // return_err,
+  //   ErrorTrait,
+  //   // BasicError,
+  // };
+
   #[ doc( inline ) ]
-  pub use private::
-  {
-    err,
-    return_err,
-    ErrorTrait,
-    BasicError,
-  };
+  pub use assert::prelude::*;
+
+  #[ cfg( feature = "error_untyped" ) ]
+  #[ doc( inline ) ]
+  pub use untyped::prelude::*;
+
+  #[ cfg( feature = "error_typed" ) ]
+  #[ doc( inline ) ]
+  pub use typed::prelude::*;
 
 }
diff --git a/module/core/error_tools/src/typed.rs b/module/core/error_tools/src/error/typed.rs
similarity index 100%
rename from module/core/error_tools/src/typed.rs
rename to module/core/error_tools/src/error/typed.rs
diff --git a/module/core/error_tools/src/untyped.rs b/module/core/error_tools/src/error/untyped.rs
similarity index 86%
rename from module/core/error_tools/src/untyped.rs
rename to module/core/error_tools/src/error/untyped.rs
index df16162bab..17e335473a 100644
--- a/module/core/error_tools/src/untyped.rs
+++ b/module/core/error_tools/src/error/untyped.rs
@@ -13,6 +13,7 @@ pub use own::*;
 pub mod own
 {
   use super::*;
+
   #[ doc( inline ) ]
   pub use orphan::*;
 
@@ -24,6 +25,10 @@ pub mod own
     Error,
     Ok,
     Result,
+    format_err,
+    bail as return_err,
+    ensure,
+    bail,
   };
 
 }
@@ -39,13 +44,13 @@ pub mod orphan
   #[ doc( inline ) ]
   pub use exposed::*;
 
-  #[ doc( inline ) ]
-  pub use ::anyhow::
-  {
-    format_err,
-    ensure,
-    bail,
-  };
+  // #[ doc( inline ) ]
+  // pub use ::anyhow::
+  // {
+  //   format_err,
+  //   ensure,
+  //   bail,
+  // };
 
 }
 
diff --git a/module/core/error_tools/src/lib.rs b/module/core/error_tools/src/lib.rs
index 30a25af03b..9ba2500d42 100644
--- a/module/core/error_tools/src/lib.rs
+++ b/module/core/error_tools/src/lib.rs
@@ -4,10 +4,6 @@
 #![ doc( html_root_url = "https://docs.rs/error_tools/latest/error_tools/" ) ]
 #![ doc = include_str!( concat!( env!( "CARGO_MANIFEST_DIR" ), "/", "Readme.md" ) ) ]
 
-/// Assertions.
-#[ cfg( feature = "enabled" ) ]
-pub mod assert;
-
 /// Alias for std::error::BasicError.
 #[ cfg( feature = "enabled" ) ]
 #[ cfg( not( feature = "no_std" ) ) ]
@@ -19,27 +15,15 @@ pub mod dependency
 {
 
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   #[ cfg( feature = "error_typed" ) ]
   pub use ::thiserror;
 
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   #[ cfg( feature = "error_untyped" ) ]
   pub use ::anyhow;
 
 }
 
-#[ cfg( feature = "enabled" ) ]
-#[ cfg( feature = "error_typed" ) ]
-/// Typed exceptions handling mechanism.
-pub mod typed;
-
-#[ cfg( feature = "enabled" ) ]
-#[ cfg( feature = "error_untyped" ) ]
-/// Untyped exceptions handling mechanism.
-pub mod untyped;
-
 #[ cfg( feature = "enabled" ) ]
 #[ doc( inline ) ]
 #[ allow( unused_imports ) ]
@@ -51,27 +35,9 @@ pub use own::*;
 pub mod own
 {
   use super::*;
-  #[ allow( unused_imports ) ]
-  use super::*;
-
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use assert::orphan::*;
 
-  #[ cfg( not( feature = "no_std" ) ) ]
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use error::orphan::*;
-
-  #[ cfg( feature = "error_untyped" ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use untyped::orphan::*;
-
-  #[ cfg( feature = "error_typed" ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use typed::orphan::*;
+  pub use error::own::*;
 
 }
 
@@ -85,6 +51,9 @@ pub mod orphan
   #[ doc( inline ) ]
   pub use exposed::*;
 
+  #[ doc( inline ) ]
+  pub use error::orphan::*;
+
 }
 
 /// Exposed namespace of the module.
@@ -95,28 +64,11 @@ pub mod exposed
   use super::*;
 
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   pub use prelude::*;
 
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use assert::exposed::*;
-
-  #[ cfg( not( feature = "no_std" ) ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   pub use error::exposed::*;
 
-  #[ cfg( feature = "error_untyped" ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use untyped::exposed::*;
-
-  #[ cfg( feature = "error_typed" ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use typed::exposed::*;
-
 }
 
 /// Prelude to use essentials: `use my_module::prelude::*`.
@@ -125,26 +77,8 @@ pub mod exposed
 pub mod prelude
 {
   use super::*;
-  #[ allow( unused_imports ) ]
-  use super::*;
-
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use assert::prelude::*;
 
-  #[ cfg( not( feature = "no_std" ) ) ]
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   pub use error::prelude::*;
 
-  #[ cfg( feature = "error_untyped" ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use untyped::prelude::*;
-
-  #[ cfg( feature = "error_typed" ) ]
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use typed::prelude::*;
-
 }
diff --git a/module/core/error_tools/src/result.rs b/module/core/error_tools/src/result.rs
deleted file mode 100644
index ea5a3c3b48..0000000000
--- a/module/core/error_tools/src/result.rs
+++ /dev/null
@@ -1,43 +0,0 @@
-// /// Internal namespace.
-// mod private
-// {
-//   use crate::error::BasicError;
-//
-//   /// Type alias for Result with BasicError.
-//   pub type Result< T, E = BasicError > = std::result::Result< T, E >;
-// }
-//
-// /// Own namespace of the module.
-// pub mod own
-// {
-//   #[ doc( inline ) ]
-//   #[ allow( unused_imports ) ]
-//   pub use orphan::*;
-// }
-//
-// #[ doc( inline ) ]
-// #[ allow( unused_imports ) ]
-// pub use own::*;
-//
-// /// Shared with parent namespace of the module
-// pub mod orphan
-// {
-//   #[ doc( inline ) ]
-//   #[ allow( unused_imports ) ]
-//   pub use exposed::*;
-// }
-//
-// /// Exposed namespace of the module.
-// pub mod exposed
-// {
-//   #[ doc( inline ) ]
-//   #[ allow( unused_imports ) ]
-//   pub use prelude::*;
-// }
-//
-// /// Prelude to use essentials: `use my_module::prelude::*`.
-// pub mod prelude
-// {
-//   pub use private::Result;
-// }
-//
diff --git a/module/core/error_tools/tests/inc/basic_test.rs b/module/core/error_tools/tests/inc/basic_test.rs
index 61462b17f9..32cb4c4bba 100644
--- a/module/core/error_tools/tests/inc/basic_test.rs
+++ b/module/core/error_tools/tests/inc/basic_test.rs
@@ -1,5 +1,5 @@
 #![ allow( deprecated ) ]
-#![ allow( unused_imports ) ]
+// #![ allow( unused_imports ) ]
 use super::*;
 
 //
@@ -7,117 +7,116 @@ use super::*;
 #[ cfg( not( feature = "no_std" ) ) ]
 tests_impls!
 {
-  fn basic()
-  {
-    use std::error::Error;
-
-    // test.case( "basic" );
-
-    let err1 = the_module::BasicError::new( "Some error" );
-    a_id!( err1.to_string(), "Some error" );
-    a_id!( err1.description(), "Some error" );
-    a_id!( err1.msg(), "Some error" );
-    a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
-
-    // test.case( "compare" );
-
-    let err1 = the_module::BasicError::new( "Some error" );
-    let err2 = the_module::BasicError::new( "Some error" );
-    a_id!( err1, err2 );
-    a_id!( err1.description(), err2.description() );
-
-    // test.case( "clone" );
-
-    let err1 = the_module::BasicError::new( "Some error" );
-    let err2 = err1.clone();
-    a_id!( err1, err2 );
-    a_id!( err1.description(), err2.description() );
-  }
-
-  //
-
-  fn use1()
-  {
-    use std::error::Error as ErrorTrait;
-    use the_module::BasicError as Error;
-
-    // test.case( "basic" );
-
-    let err1 = Error::new( "Some error" );
-    a_id!( err1.to_string(), "Some error" );
-    a_id!( err1.description(), "Some error" );
-    a_id!( err1.msg(), "Some error" );
-    a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
-  }
-
-  //
-
-  fn use2()
-  {
-    use the_module::{ BasicError, ErrorTrait };
-
-    // test.case( "basic" );
-
-    let err1 = BasicError::new( "Some error" );
-    a_id!( err1.to_string(), "Some error" );
-    a_id!( err1.description(), "Some error" );
-    a_id!( err1.msg(), "Some error" );
-    a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
-  }
-
-  //
-
-  fn use3()
-  {
-    use std::error::Error;
-
-    // test.case( "basic" );
-
-    let err1 = the_module::BasicError::new( "Some error" );
-    a_id!( err1.to_string(), "Some error" );
-    a_id!( err1.description(), "Some error" );
-    a_id!( err1.msg(), "Some error" );
-    a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
-  }
-
-  //
-
-  fn err_basic()
-  {
-    // test.case( "basic" );
-    let err : the_module::BasicError = the_module::err!( "abc" );
-    a_id!( err.to_string(), "abc" );
-
-    // test.case( "with args" );
-    let err : the_module::BasicError = the_module::err!( "abc{}{}", "def", "ghi" );
-    a_id!( err.to_string(), "abcdefghi" );
-  }
+//   fn basic()
+//   {
+//     use std::error::Error;
+//
+//     // test.case( "basic" );
+//
+//     let err1 = the_module::BasicError::new( "Some error" );
+//     a_id!( err1.to_string(), "Some error" );
+//     a_id!( err1.description(), "Some error" );
+//     a_id!( err1.msg(), "Some error" );
+//     a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
+//
+//     // test.case( "compare" );
+//
+//     let err1 = the_module::BasicError::new( "Some error" );
+//     let err2 = the_module::BasicError::new( "Some error" );
+//     a_id!( err1, err2 );
+//     a_id!( err1.description(), err2.description() );
+//
+//     // test.case( "clone" );
+//
+//     let err1 = the_module::BasicError::new( "Some error" );
+//     let err2 = err1.clone();
+//     a_id!( err1, err2 );
+//     a_id!( err1.description(), err2.description() );
+//   }
 
   //
 
-  fn sample()
-  {
-    #[ cfg( not( feature = "no_std" ) ) ]
-    fn f1() -> the_module::untyped::Result< () >
-    {
-      let _read = std::fs::read_to_string( "Cargo.toml" )?;
-      Err( the_module::BasicError::new( "Some error" ).into() )
-      // the_module::BasicError::new( "Some error" ).into()
-      // zzz : make it working maybe
-    }
-
-    #[ cfg( not( feature = "no_std" ) ) ]
-    {
-      let err = f1();
-      println!( "{err:#?}" );
-      // < Err(
-      // <    BasicError {
-      // <        msg: "Some error",
-      // <    },
-      // < )
-    }
-  }
-
+//   fn use1()
+//   {
+//     use std::error::Error as ErrorTrait;
+//     use the_module::BasicError as Error;
+//
+//     // test.case( "basic" );
+//
+//     let err1 = Error::new( "Some error" );
+//     a_id!( err1.to_string(), "Some error" );
+//     a_id!( err1.description(), "Some error" );
+//     a_id!( err1.msg(), "Some error" );
+//     a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
+//   }
+//
+//   //
+//
+//   fn use2()
+//   {
+//     use the_module::{ BasicError, ErrorTrait };
+//
+//     // test.case( "basic" );
+//
+//     let err1 = BasicError::new( "Some error" );
+//     a_id!( err1.to_string(), "Some error" );
+//     a_id!( err1.description(), "Some error" );
+//     a_id!( err1.msg(), "Some error" );
+//     a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
+//   }
+//
+//   //
+//
+//   fn use3()
+//   {
+//     use std::error::Error;
+//
+//     // test.case( "basic" );
+//
+//     let err1 = the_module::BasicError::new( "Some error" );
+//     a_id!( err1.to_string(), "Some error" );
+//     a_id!( err1.description(), "Some error" );
+//     a_id!( err1.msg(), "Some error" );
+//     a_id!( format!( "err1 : {}", err1 ), "err1 : Some error" );
+//   }
+//
+//   //
+//
+//   fn err_basic()
+//   {
+//     // test.case( "basic" );
+//     let err : the_module::BasicError = the_module::err!( "abc" );
+//     a_id!( err.to_string(), "abc" );
+//
+//     // test.case( "with args" );
+//     let err : the_module::BasicError = the_module::err!( "abc{}{}", "def", "ghi" );
+//     a_id!( err.to_string(), "abcdefghi" );
+//   }
+//
+//   //
+//
+//   fn sample()
+//   {
+//     #[ cfg( not( feature = "no_std" ) ) ]
+//     fn f1() -> the_module::untyped::Result< () >
+//     {
+//       let _read = std::fs::read_to_string( "Cargo.toml" )?;
+//       Err( the_module::BasicError::new( "Some error" ).into() )
+//       // the_module::BasicError::new( "Some error" ).into()
+//       // zzz : make it working maybe
+//     }
+//
+//     #[ cfg( not( feature = "no_std" ) ) ]
+//     {
+//       let err = f1();
+//       println!( "{err:#?}" );
+//       // < Err(
+//       // <    BasicError {
+//       // <        msg: "Some error",
+//       // <    },
+//       // < )
+//     }
+//   }
 
 }
 
@@ -126,10 +125,10 @@ tests_impls!
 #[ cfg( not( feature = "no_std" ) ) ]
 tests_index!
 {
-  basic,
-  use1,
-  use2,
-  use3,
-  err_basic,
-  sample,
+  // basic,
+  // use1,
+  // use2,
+  // use3,
+  // err_basic,
+  // sample,
 }
diff --git a/module/core/error_tools/tests/inc/mod.rs b/module/core/error_tools/tests/inc/mod.rs
index 256c6e20bd..dc239e680e 100644
--- a/module/core/error_tools/tests/inc/mod.rs
+++ b/module/core/error_tools/tests/inc/mod.rs
@@ -1,8 +1,10 @@
 #[ allow( unused_imports ) ]
 use super::*;
 
-mod assert_test;
 mod basic_test;
+mod namespace_test;
+
+mod assert_test;
 #[ cfg( not( feature = "no_std" ) ) ]
 mod err_with_test;
 mod untyped_test;
diff --git a/module/core/error_tools/tests/inc/namespace_test.rs b/module/core/error_tools/tests/inc/namespace_test.rs
new file mode 100644
index 0000000000..92e96b0610
--- /dev/null
+++ b/module/core/error_tools/tests/inc/namespace_test.rs
@@ -0,0 +1,12 @@
+use super::*;
+
+#[ test ]
+fn exposed_main_namespace()
+{
+
+  the_module::error::debug_assert_id!( 1, 1 );
+  the_module::exposed::error::debug_assert_id!( 1, 1 );
+  use the_module::exposed::*;
+  error::debug_assert_id!( 1, 1 );
+
+}
\ No newline at end of file
diff --git a/module/core/error_tools/tests/tests.rs b/module/core/error_tools/tests/tests.rs
index 0374c10521..f217bd0119 100644
--- a/module/core/error_tools/tests/tests.rs
+++ b/module/core/error_tools/tests/tests.rs
@@ -1,7 +1,6 @@
+#![ allow( unused_imports ) ]
 
-#[ allow( unused_imports ) ]
 use error_tools as the_module;
-#[ allow( unused_imports ) ]
 use test_tools::exposed::*;
 
 mod inc;
diff --git a/module/core/meta_tools/Cargo.toml b/module/core/meta_tools/Cargo.toml
index 0fc0b3c61d..842fa3143e 100644
--- a/module/core/meta_tools/Cargo.toml
+++ b/module/core/meta_tools/Cargo.toml
@@ -32,7 +32,7 @@ default = [
   "meta_for_each",
   "meta_impls_index",
   # "meta_mod_interface",
-  "meta_constructors",
+  # "meta_constructors",
   "meta_idents_concat",
 ]
 full = [
@@ -40,7 +40,7 @@ full = [
   "meta_for_each",
   "meta_impls_index",
   # "meta_mod_interface",
-  "meta_constructors",
+  # "meta_constructors",
   "meta_idents_concat",
 ]
 no_std = []
@@ -52,14 +52,14 @@ meta_impls_index = [ "impls_index/enabled" ]
 meta_mod_interface = [ "mod_interface/enabled" ]
 # xxx : qqq : make mod_interface optional maybe
 
-meta_constructors = [ "literally" ]
+# meta_constructors = [ "literally" ]
 meta_idents_concat = [ "paste" ]
 
 [dependencies]
 
-## external
-literally = { version = "~0.1.3", optional = true, default-features = false }
-paste = { version = "~1.0.14", optional = true, default-features = false }
+# ## external
+# literally = { version = "~0.1.3", optional = true, default-features = false }
+paste = { workspace = true, optional = true, default-features = false }
 
 ## internal
 impls_index = { workspace = true }
diff --git a/module/core/meta_tools/Readme.md b/module/core/meta_tools/Readme.md
index 0d472b069f..c43c980e94 100644
--- a/module/core/meta_tools/Readme.md
+++ b/module/core/meta_tools/Readme.md
@@ -7,21 +7,6 @@
 
 Collection of general purpose meta tools.
 
-### Basic use-case  :: variadic constructor of collections
-
-Among other useful meta tools the module aggregates variadic constructors of collections. For example macro `hmap!` for constructing a hash map.
-
-<!-- {{# generate.module{} #}} -->
-
-```rust
-use meta_tools::*;
-
-let meta_map = hmap! { 3 => 13 };
-let mut std_map = std::collections::HashMap::new();
-std_map.insert( 3, 13 );
-assert_eq!( meta_map, std_map );
-```
-
 ### Basic Use Case :: function-style call
 
 Apply a macro for each element of a list.
diff --git a/module/core/meta_tools/examples/meta_tools_trivial.rs b/module/core/meta_tools/examples/meta_tools_trivial.rs
index 75d17ddace..983e55c9d6 100644
--- a/module/core/meta_tools/examples/meta_tools_trivial.rs
+++ b/module/core/meta_tools/examples/meta_tools_trivial.rs
@@ -3,8 +3,10 @@ use meta_tools::*;
 
 fn main()
 {
-  let meta_map = hmap! { 3 => 13 };
-  let mut std_map = std::collections::HashMap::new();
-  std_map.insert( 3, 13 );
-  assert_eq!( meta_map, std_map );
+  for_each!( dbg, "a", "b", "c" );
+
+  // generates
+  dbg!( "a" );
+  dbg!( "b" );
+  dbg!( "c" );
 }
diff --git a/module/core/meta_tools/src/lib.rs b/module/core/meta_tools/src/lib.rs
index 352f7e0f3b..391eaf5050 100644
--- a/module/core/meta_tools/src/lib.rs
+++ b/module/core/meta_tools/src/lib.rs
@@ -17,8 +17,8 @@ pub mod dependency
   #[ cfg( feature = "meta_impls_index" ) ]
   pub use ::impls_index;
 
-  #[ cfg( feature = "meta_constructors" ) ]
-  pub use ::literally;
+  // #[ cfg( feature = "meta_constructors" ) ]
+  // pub use ::literally;
   #[ cfg( feature = "meta_idents_concat" ) ]
   pub use ::paste;
 
diff --git a/module/core/meta_tools/src/meta.rs b/module/core/meta_tools/src/meta.rs
index e05ad7deec..1cda0b024d 100644
--- a/module/core/meta_tools/src/meta.rs
+++ b/module/core/meta_tools/src/meta.rs
@@ -22,8 +22,8 @@ mod_interface::mod_interface!
   // #[ cfg( feature = "meta_mod_interface" ) ]
   prelude use ::mod_interface::mod_interface;
 
-  #[ cfg( feature = "meta_constructors" ) ]
-  prelude use ::literally::*;
+  // #[ cfg( feature = "meta_constructors" ) ]
+  // prelude use ::literally::*;
   #[ cfg( feature = "meta_idents_concat" ) ]
   prelude use ::paste::paste as meta_idents_concat;
 
diff --git a/module/core/meta_tools/tests/inc/meta_constructor_test.rs b/module/core/meta_tools/tests/inc/meta_constructor_test.rs
index acee680259..d4cffdf307 100644
--- a/module/core/meta_tools/tests/inc/meta_constructor_test.rs
+++ b/module/core/meta_tools/tests/inc/meta_constructor_test.rs
@@ -1,50 +1,50 @@
-use super::*;
-
-//
-
-tests_impls!
-{
-
-  fn hash_map()
-  {
-
-    // test.case( "empty" );
-    let got : std::collections::HashMap< i32, i32 > = the_module::hmap!{};
-    let exp = std::collections::HashMap::new();
-    a_id!( got, exp );
-
-    // test.case( "single entry" );
-    let got = the_module::hmap!{ 3 => 13 };
-    let mut exp = std::collections::HashMap::new();
-    exp.insert( 3, 13 );
-    a_id!( got, exp );
-
-  }
-
-  //
-
-
-  fn hash_set()
-  {
-
-    // test.case( "empty" );
-    let got : std::collections::HashSet< i32 > = the_module::hset!{};
-    let exp = std::collections::HashSet::new();
-    a_id!( got, exp );
-
-    // test.case( "single entry" );
-    let got = the_module::hset!{ 13 };
-    let mut exp = std::collections::HashSet::new();
-    exp.insert( 13 );
-    a_id!( got, exp );
-
-  }
-}
-
-//
-
-tests_index!
-{
-  hash_map,
-  hash_set,
-}
+// use super::*;
+//
+// //
+//
+// tests_impls!
+// {
+//
+//   fn hash_map()
+//   {
+//
+//     // test.case( "empty" );
+//     let got : std::collections::HashMap< i32, i32 > = the_module::hmap!{};
+//     let exp = std::collections::HashMap::new();
+//     a_id!( got, exp );
+//
+//     // test.case( "single entry" );
+//     let got = the_module::hmap!{ 3 => 13 };
+//     let mut exp = std::collections::HashMap::new();
+//     exp.insert( 3, 13 );
+//     a_id!( got, exp );
+//
+//   }
+//
+//   //
+//
+//
+//   fn hash_set()
+//   {
+//
+//     // test.case( "empty" );
+//     let got : std::collections::HashSet< i32 > = the_module::hset!{};
+//     let exp = std::collections::HashSet::new();
+//     a_id!( got, exp );
+//
+//     // test.case( "single entry" );
+//     let got = the_module::hset!{ 13 };
+//     let mut exp = std::collections::HashSet::new();
+//     exp.insert( 13 );
+//     a_id!( got, exp );
+//
+//   }
+// }
+//
+// //
+//
+// tests_index!
+// {
+//   hash_map,
+//   hash_set,
+// }
diff --git a/module/core/meta_tools/tests/inc/mod.rs b/module/core/meta_tools/tests/inc/mod.rs
index 9fc942d2c2..98e402d4c3 100644
--- a/module/core/meta_tools/tests/inc/mod.rs
+++ b/module/core/meta_tools/tests/inc/mod.rs
@@ -1,17 +1,17 @@
 #[ allow( unused_imports ) ]
 use super::*;
 
-#[ cfg( any( feature = "meta_constructors", feature = "meta_constructors" ) ) ]
-mod meta_constructor_test;
+// #[ cfg( any( feature = "meta_constructors", feature = "meta_constructors" ) ) ]
+// mod meta_constructor_test;
 
 #[ cfg( any( feature = "meta_idents_concat", feature = "meta_idents_concat" ) ) ]
 mod indents_concat_test;
 
-#[ cfg( any( feature = "for_each", feature = "meta_for_each" ) ) ]
+#[ cfg( any( feature = "meta_for_each" ) ) ]
 #[ path = "../../../for_each/tests/inc/mod.rs" ]
 mod for_each_test;
 
-#[ cfg( any( feature = "impls_index", feature = "meta_impls_index" ) ) ]
+#[ cfg( any( feature = "meta_impls_index" ) ) ]
 #[ path = "../../../impls_index/tests/inc/mod.rs" ]
 mod impls_index;
 
diff --git a/module/core/mod_interface/Readme.md b/module/core/mod_interface/Readme.md
index 47115efb68..d9b6f668c5 100644
--- a/module/core/mod_interface/Readme.md
+++ b/module/core/mod_interface/Readme.md
@@ -25,7 +25,7 @@ This example demonstrates how to use the `mod_interface` crate to organize a Rus
 use mod_interface::mod_interface;
 
 // Define a module named `child`.
-mod child
+pub mod child
 {
 
   // Define a private namespace for all its items.
@@ -162,6 +162,7 @@ pub mod own
   use super::*;
   pub use orphan::*;
   pub use super::child::orphan::*;
+  pub use super::child;
 }
 
 /// Orphan namespace of the module.
diff --git a/module/core/mod_interface/examples/mod_interface_trivial/src/main.rs b/module/core/mod_interface/examples/mod_interface_trivial/src/main.rs
index 420a6c9fb4..f834f8b12f 100644
--- a/module/core/mod_interface/examples/mod_interface_trivial/src/main.rs
+++ b/module/core/mod_interface/examples/mod_interface_trivial/src/main.rs
@@ -3,7 +3,7 @@
 use mod_interface::mod_interface;
 
 /// Children.
-mod child;
+pub mod child;
 
 // Priave namespaces is necessary.
 mod private {}
diff --git a/module/core/mod_interface/tests/inc/derive/attr_debug/mod.rs b/module/core/mod_interface/tests/inc/derive/attr_debug/mod.rs
index 57b54aff39..7b425682cc 100644
--- a/module/core/mod_interface/tests/inc/derive/attr_debug/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/attr_debug/mod.rs
@@ -3,7 +3,7 @@ use super::*;
 
 mod private {}
 
-mod_interface!
+the_module::mod_interface!
 {
   // #![ debug ]
 
diff --git a/module/core/mod_interface/tests/inc/derive/layer/mod.rs b/module/core/mod_interface/tests/inc/derive/layer/mod.rs
index d8e79fb20b..8a567560f7 100644
--- a/module/core/mod_interface/tests/inc/derive/layer/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer/mod.rs
@@ -6,7 +6,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// layer_a
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_a.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_a.rs
index dfffa8d8a8..082005e6be 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_a.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_a.rs
@@ -33,7 +33,7 @@ mod private
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   // orphan use super::private::
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_b.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_b.rs
index 9f17f61637..1d265d3c4f 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_b.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer/layer_b.rs
@@ -39,7 +39,7 @@ pub struct SubStruct2
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own use layer_b_own;
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer/mod.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer/mod.rs
index 6cf3f6db29..219360f435 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer/mod.rs
@@ -11,7 +11,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// layer_a
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_a.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_a.rs
index dfffa8d8a8..082005e6be 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_a.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_a.rs
@@ -33,7 +33,7 @@ mod private
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   // orphan use super::private::
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_b.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_b.rs
index 9f17f61637..1d265d3c4f 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_b.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/layer_b.rs
@@ -39,7 +39,7 @@ pub struct SubStruct2
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own use layer_b_own;
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/mod.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/mod.rs
index 09c564f64b..b0fc4d5d70 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_cfg/mod.rs
@@ -11,7 +11,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// layer_a
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_a.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_a.rs
index 8d8d6b1faf..c71e0af7d2 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_a.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_a.rs
@@ -33,7 +33,7 @@ mod private
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own use { layer_a_own };
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_b.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_b.rs
index 9f17f61637..1d265d3c4f 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_b.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/layer_b.rs
@@ -39,7 +39,7 @@ pub struct SubStruct2
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own use layer_b_own;
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/mod.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/mod.rs
index c34df1c831..0d2ec22d26 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use/mod.rs
@@ -12,11 +12,11 @@ mod private
 }
 
 /// layer_a
-mod layer_a;
+pub mod layer_a;
 /// layer_b
-mod layer_b;
+pub mod layer_b;
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// layer_a
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_a.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_a.rs
index 8d8d6b1faf..c71e0af7d2 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_a.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_a.rs
@@ -33,7 +33,7 @@ mod private
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own use { layer_a_own };
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_b.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_b.rs
index 9f17f61637..1d265d3c4f 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_b.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/layer_b.rs
@@ -39,7 +39,7 @@ pub struct SubStruct2
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own use layer_b_own;
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/mod.rs b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/mod.rs
index 4774b23347..c20f8d770a 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_layer_separate_use_two/mod.rs
@@ -12,11 +12,11 @@ mod private
 }
 
 /// layer_a
-mod layer_a;
+pub mod layer_a;
 /// layer_b
-mod layer_b;
+pub mod layer_b;
 
-mod_interface!
+the_module::mod_interface!
 {
 
   // zzz : test with `layer { layer_a, layer_a };`
diff --git a/module/core/mod_interface/tests/inc/derive/layer_have_mod_cfg/mod.rs b/module/core/mod_interface/tests/inc/derive/layer_have_mod_cfg/mod.rs
index 2188f4a6b3..38ff58d0eb 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_have_mod_cfg/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_have_mod_cfg/mod.rs
@@ -11,7 +11,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// mod_a
diff --git a/module/core/mod_interface/tests/inc/derive/layer_unknown_vis/trybuild.stderr b/module/core/mod_interface/tests/inc/derive/layer_unknown_vis/trybuild.stderr
index 2d2aa78ea8..125e29bbdb 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_unknown_vis/trybuild.stderr
+++ b/module/core/mod_interface/tests/inc/derive/layer_unknown_vis/trybuild.stderr
@@ -1,4 +1,4 @@
-error: expected one of: `mod`, `use`, `layer`
+error: expected one of: `mod`, `use`, `layer`, `reuse`
  --> tests/inc/derive/layer_unknown_vis/mod.rs
   |
   |   xyz layer layer_a;
diff --git a/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_a.rs b/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_a.rs
index dfffa8d8a8..082005e6be 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_a.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_a.rs
@@ -33,7 +33,7 @@ mod private
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   // orphan use super::private::
diff --git a/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_b.rs b/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_b.rs
index 9f17f61637..1d265d3c4f 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_b.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_use_cfg/layer_b.rs
@@ -39,7 +39,7 @@ pub struct SubStruct2
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own use layer_b_own;
diff --git a/module/core/mod_interface/tests/inc/derive/layer_use_cfg/mod.rs b/module/core/mod_interface/tests/inc/derive/layer_use_cfg/mod.rs
index 0c730db3a7..d9eedf0a3e 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_use_cfg/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_use_cfg/mod.rs
@@ -12,12 +12,13 @@ mod private
 }
 
 /// layer_a
-mod layer_a;
+pub mod layer_a;
 /// layer_b
-mod layer_b;
+pub mod layer_b;
 
-mod_interface!
+the_module::mod_interface!
 {
+  // #![ debug ]
 
   /// layer_a
   use super::layer_a;
@@ -33,4 +34,3 @@ mod_interface!
 //
 
 include!( "../../only_test/layer_simple_only_test.rs" );
-
diff --git a/module/core/mod_interface/tests/inc/derive/layer_use_macro/layer_a.rs b/module/core/mod_interface/tests/inc/derive/layer_use_macro/layer_a.rs
index 12db22ecfc..b37c839cd0 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_use_macro/layer_a.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_use_macro/layer_a.rs
@@ -35,7 +35,7 @@ mod private
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   // exposed( crate ) use macro1;
diff --git a/module/core/mod_interface/tests/inc/derive/layer_use_macro/mod.rs b/module/core/mod_interface/tests/inc/derive/layer_use_macro/mod.rs
index 1bb9569c90..67a972b145 100644
--- a/module/core/mod_interface/tests/inc/derive/layer_use_macro/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/layer_use_macro/mod.rs
@@ -11,7 +11,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// layer_a
diff --git a/module/core/mod_interface/tests/inc/derive/micro_modules/mod.rs b/module/core/mod_interface/tests/inc/derive/micro_modules/mod.rs
index 80d4c7218a..57adff6ff2 100644
--- a/module/core/mod_interface/tests/inc/derive/micro_modules/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/micro_modules/mod.rs
@@ -6,7 +6,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
   // #![ debug ]
 
diff --git a/module/core/mod_interface/tests/inc/derive/micro_modules_bad_vis/trybuild.stderr b/module/core/mod_interface/tests/inc/derive/micro_modules_bad_vis/trybuild.stderr
index b84160eec0..d73c3c374c 100644
--- a/module/core/mod_interface/tests/inc/derive/micro_modules_bad_vis/trybuild.stderr
+++ b/module/core/mod_interface/tests/inc/derive/micro_modules_bad_vis/trybuild.stderr
@@ -1,4 +1,4 @@
-error: To include a non-standard module use either [ private, protected, orphan, exposed, prelude ] visibility:
+error: To include a non-standard module use either [ private, own, orphan, exposed, prelude ] visibility:
          #[doc = " mod_exposed"] pub mod mod_exposed;
  --> tests/inc/derive/micro_modules_bad_vis/mod.rs
   |
diff --git a/module/core/mod_interface/tests/inc/derive/micro_modules_glob/mod.rs b/module/core/mod_interface/tests/inc/derive/micro_modules_glob/mod.rs
index 40ccb61f64..b9c78c9198 100644
--- a/module/core/mod_interface/tests/inc/derive/micro_modules_glob/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/micro_modules_glob/mod.rs
@@ -10,7 +10,7 @@ mod private
 
 //
 
-crate::mod_interface!
+crate::the_module::mod_interface!
 {
   own use
   {
diff --git a/module/core/mod_interface/tests/inc/derive/micro_modules_two/mod.rs b/module/core/mod_interface/tests/inc/derive/micro_modules_two/mod.rs
index 9071caf2d1..c62e6f7e18 100644
--- a/module/core/mod_interface/tests/inc/derive/micro_modules_two/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/micro_modules_two/mod.rs
@@ -6,7 +6,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// mod_own1
diff --git a/module/core/mod_interface/tests/inc/derive/micro_modules_two_joined/mod.rs b/module/core/mod_interface/tests/inc/derive/micro_modules_two_joined/mod.rs
index ced5712479..de2d1c2e88 100644
--- a/module/core/mod_interface/tests/inc/derive/micro_modules_two_joined/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/micro_modules_two_joined/mod.rs
@@ -6,7 +6,7 @@ mod private
 {
 }
 
-mod_interface!
+the_module::mod_interface!
 {
 
   own mod
diff --git a/module/core/mod_interface/tests/inc/derive/micro_modules_unknown_vis/trybuild.stderr b/module/core/mod_interface/tests/inc/derive/micro_modules_unknown_vis/trybuild.stderr
index 8df4ef8899..0fd927c7e0 100644
--- a/module/core/mod_interface/tests/inc/derive/micro_modules_unknown_vis/trybuild.stderr
+++ b/module/core/mod_interface/tests/inc/derive/micro_modules_unknown_vis/trybuild.stderr
@@ -1,4 +1,4 @@
-error: expected one of: `mod`, `use`, `layer`
+error: expected one of: `mod`, `use`, `layer`, `reuse`
  --> tests/inc/derive/micro_modules_unknown_vis/mod.rs
   |
   |   not_vis mod mod_exposed;
diff --git a/module/core/mod_interface/tests/inc/derive/reuse_basic/child.rs b/module/core/mod_interface/tests/inc/derive/reuse_basic/child.rs
index d94a40b5bd..19fcd7abde 100644
--- a/module/core/mod_interface/tests/inc/derive/reuse_basic/child.rs
+++ b/module/core/mod_interface/tests/inc/derive/reuse_basic/child.rs
@@ -6,7 +6,7 @@ mod private
   pub struct Prelude;
 }
 
-crate::mod_interface!
+crate::the_module::mod_interface!
 {
   own use Own;
   orphan use Orphan;
diff --git a/module/core/mod_interface/tests/inc/derive/reuse_basic/mod.rs b/module/core/mod_interface/tests/inc/derive/reuse_basic/mod.rs
index 55daeb2a1c..89ae6afbe8 100644
--- a/module/core/mod_interface/tests/inc/derive/reuse_basic/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/reuse_basic/mod.rs
@@ -10,7 +10,7 @@ mod child;
 
 //
 
-crate::mod_interface!
+crate::the_module::mod_interface!
 {
   reuse child;
 }
diff --git a/module/core/mod_interface/tests/inc/derive/use_as/derive.rs b/module/core/mod_interface/tests/inc/derive/use_as/derive.rs
index a70260fc3c..1d0b464591 100644
--- a/module/core/mod_interface/tests/inc/derive/use_as/derive.rs
+++ b/module/core/mod_interface/tests/inc/derive/use_as/derive.rs
@@ -6,7 +6,7 @@ pub mod layer_x;
 
 mod private {}
 
-mod_interface!
+the_module::mod_interface!
 {
   // #![ debug ]
 
diff --git a/module/core/mod_interface/tests/inc/derive/use_bad_vis/trybuild.stderr b/module/core/mod_interface/tests/inc/derive/use_bad_vis/trybuild.stderr
index b63d146f04..cb5d08876c 100644
--- a/module/core/mod_interface/tests/inc/derive/use_bad_vis/trybuild.stderr
+++ b/module/core/mod_interface/tests/inc/derive/use_bad_vis/trybuild.stderr
@@ -1,4 +1,4 @@
-error: Use either [ private, protected, orphan, exposed, prelude ] visibility:
+error: Use either [ private, own, orphan, exposed, prelude ] visibility:
          #[doc = " layer_a"] pub use;
   --> tests/inc/derive/use_bad_vis/mod.rs
    |
diff --git a/module/core/mod_interface/tests/inc/derive/use_basic/mod.rs b/module/core/mod_interface/tests/inc/derive/use_basic/mod.rs
index fe3862d5b3..4afc8262c6 100644
--- a/module/core/mod_interface/tests/inc/derive/use_basic/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/use_basic/mod.rs
@@ -1,12 +1,14 @@
 
 use super::*;
 
-mod layer_a;
-mod layer_b;
+// private layer
+pub mod layer_a;
+// private layer
+pub mod layer_b;
 
 mod private {}
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// layer_a
diff --git a/module/core/mod_interface/tests/inc/derive/use_layer/layer_a.rs b/module/core/mod_interface/tests/inc/derive/use_layer/layer_a.rs
index 14ecb25b3e..1b892a03b1 100644
--- a/module/core/mod_interface/tests/inc/derive/use_layer/layer_a.rs
+++ b/module/core/mod_interface/tests/inc/derive/use_layer/layer_a.rs
@@ -34,7 +34,7 @@ pub struct SubStruct4
 
 //
 
-mod_interface!
+the_module::mod_interface!
 {
 
   orphan use ::std::vec::Vec;
diff --git a/module/core/mod_interface/tests/inc/derive/use_layer/mod.rs b/module/core/mod_interface/tests/inc/derive/use_layer/mod.rs
index a7f1790c60..4b4bfaa581 100644
--- a/module/core/mod_interface/tests/inc/derive/use_layer/mod.rs
+++ b/module/core/mod_interface/tests/inc/derive/use_layer/mod.rs
@@ -6,7 +6,7 @@ mod tools
   pub use super::super::*;
 }
 
-mod layer_a;
+pub mod layer_a;
 
 /// SuperStruct1.
 #[ derive( Debug, PartialEq ) ]
@@ -16,7 +16,7 @@ pub struct SuperStruct1
 
 mod private {}
 
-mod_interface!
+the_module::mod_interface!
 {
 
   /// layer_a
diff --git a/module/core/mod_interface/tests/inc/derive/use_private_layers/layer_a.rs b/module/core/mod_interface/tests/inc/derive/use_private_layers/layer_a.rs
new file mode 100644
index 0000000000..8c49982711
--- /dev/null
+++ b/module/core/mod_interface/tests/inc/derive/use_private_layers/layer_a.rs
@@ -0,0 +1,63 @@
+
+/// Private namespace of the module.
+mod private
+{
+}
+
+/// Own namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod own
+{
+  use super::*;
+  #[ doc( inline ) ]
+  pub use orphan::*;
+  /// layer_a_own
+  pub fn layer_a_own() -> bool
+  {
+    true
+  }
+}
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Orphan namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+  #[ doc( inline ) ]
+  pub use exposed::*;
+  /// layer_a_orphan
+  pub fn layer_a_orphan() -> bool
+  {
+    true
+  }
+}
+
+/// Exposed namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+  #[ doc( inline ) ]
+  pub use prelude::*;
+  /// layer_a_exposed
+  pub fn layer_a_exposed() -> bool
+  {
+    true
+  }
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+  /// layer_a_prelude
+  pub fn layer_a_prelude() -> bool
+  {
+    true
+  }
+}
diff --git a/module/core/mod_interface/tests/inc/derive/use_private_layers/layer_b.rs b/module/core/mod_interface/tests/inc/derive/use_private_layers/layer_b.rs
new file mode 100644
index 0000000000..1e15689f05
--- /dev/null
+++ b/module/core/mod_interface/tests/inc/derive/use_private_layers/layer_b.rs
@@ -0,0 +1,63 @@
+
+/// Private namespace of the module.
+mod private
+{
+}
+
+/// Own namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod own
+{
+  use super::*;
+  #[ doc( inline ) ]
+  pub use orphan::*;
+  /// layer_b_own
+  pub fn layer_b_own() -> bool
+  {
+    true
+  }
+}
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Orphan namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+  #[ doc( inline ) ]
+  pub use exposed::*;
+  /// layer_b_orphan
+  pub fn layer_b_orphan() -> bool
+  {
+    true
+  }
+}
+
+/// Exposed namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+  #[ doc( inline ) ]
+  pub use prelude::*;
+  /// layer_b_exposed
+  pub fn layer_b_exposed() -> bool
+  {
+    true
+  }
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+  /// layer_b_prelude
+  pub fn layer_b_prelude() -> bool
+  {
+    true
+  }
+}
diff --git a/module/core/mod_interface/tests/inc/derive/use_private_layers/mod.rs b/module/core/mod_interface/tests/inc/derive/use_private_layers/mod.rs
new file mode 100644
index 0000000000..531513253f
--- /dev/null
+++ b/module/core/mod_interface/tests/inc/derive/use_private_layers/mod.rs
@@ -0,0 +1,28 @@
+#![ allow( dead_code ) ]
+#![ allow( unused_imports ) ]
+
+use super::*;
+
+// private layer
+mod layer_a;
+// private layer
+mod layer_b;
+
+mod private {}
+
+// xxx : qqq : make it working
+
+// the_module::mod_interface!
+// {
+//
+//   /// layer_a
+//   priv use super::layer_a;
+//
+//   /// layer_b
+//   priv use super::layer_b;
+//
+// }
+//
+// //
+//
+// include!( "../../only_test/layer_simple_only_test.rs" );
diff --git a/module/core/mod_interface/tests/inc/derive/use_unknown_vis/trybuild.stderr b/module/core/mod_interface/tests/inc/derive/use_unknown_vis/trybuild.stderr
index 530570d39a..0dc9fb08bc 100644
--- a/module/core/mod_interface/tests/inc/derive/use_unknown_vis/trybuild.stderr
+++ b/module/core/mod_interface/tests/inc/derive/use_unknown_vis/trybuild.stderr
@@ -1,4 +1,4 @@
-error: expected one of: `mod`, `use`, `layer`
+error: expected one of: `mod`, `use`, `layer`, `reuse`
  --> tests/inc/derive/use_unknown_vis/mod.rs
   |
   |   xyz use f1;
diff --git a/module/core/mod_interface/tests/inc/manual/layer/mod.rs b/module/core/mod_interface/tests/inc/manual/layer/mod.rs
index 044ff08dbf..adb8be65df 100644
--- a/module/core/mod_interface/tests/inc/manual/layer/mod.rs
+++ b/module/core/mod_interface/tests/inc/manual/layer/mod.rs
@@ -19,11 +19,13 @@ pub mod own
   #[ doc( inline ) ]
   pub use orphan::*;
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   pub use super::layer_a::orphan::*;
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   pub use super::layer_b::orphan::*;
+  #[ doc( inline ) ]
+  pub use super::layer_a;
+  #[ doc( inline ) ]
+  pub use super::layer_b;
 }
 
 #[ doc( inline ) ]
diff --git a/module/core/mod_interface/tests/inc/manual/micro_modules/mod.rs b/module/core/mod_interface/tests/inc/manual/micro_modules/mod.rs
index 65ba341ba1..5aa53251a1 100644
--- a/module/core/mod_interface/tests/inc/manual/micro_modules/mod.rs
+++ b/module/core/mod_interface/tests/inc/manual/micro_modules/mod.rs
@@ -1,3 +1,4 @@
+#![ allow( dead_code ) ]
 
 use super::*;
 
diff --git a/module/core/mod_interface/tests/inc/manual/layer_use/layer_a.rs b/module/core/mod_interface/tests/inc/manual/use_layer/layer_a.rs
similarity index 100%
rename from module/core/mod_interface/tests/inc/manual/layer_use/layer_a.rs
rename to module/core/mod_interface/tests/inc/manual/use_layer/layer_a.rs
diff --git a/module/core/mod_interface/tests/inc/manual/layer_use/layer_b.rs b/module/core/mod_interface/tests/inc/manual/use_layer/layer_b.rs
similarity index 100%
rename from module/core/mod_interface/tests/inc/manual/layer_use/layer_b.rs
rename to module/core/mod_interface/tests/inc/manual/use_layer/layer_b.rs
diff --git a/module/core/mod_interface/tests/inc/manual/layer_use/mod.rs b/module/core/mod_interface/tests/inc/manual/use_layer/mod.rs
similarity index 93%
rename from module/core/mod_interface/tests/inc/manual/layer_use/mod.rs
rename to module/core/mod_interface/tests/inc/manual/use_layer/mod.rs
index 044ff08dbf..43622260c8 100644
--- a/module/core/mod_interface/tests/inc/manual/layer_use/mod.rs
+++ b/module/core/mod_interface/tests/inc/manual/use_layer/mod.rs
@@ -24,6 +24,10 @@ pub mod own
   #[ doc( inline ) ]
   #[ allow( unused_imports ) ]
   pub use super::layer_b::orphan::*;
+  #[ doc( inline ) ]
+  pub use super::layer_a;
+  #[ doc( inline ) ]
+  pub use super::layer_b;
 }
 
 #[ doc( inline ) ]
diff --git a/module/core/mod_interface/tests/inc/mod.rs b/module/core/mod_interface/tests/inc/mod.rs
index f838c57b50..1809e2f2e8 100644
--- a/module/core/mod_interface/tests/inc/mod.rs
+++ b/module/core/mod_interface/tests/inc/mod.rs
@@ -9,7 +9,7 @@ mod manual
   mod micro_modules;
   mod micro_modules_two;
   mod layer;
-  mod layer_use;
+  mod use_layer;
 
 }
 
@@ -37,6 +37,7 @@ mod derive
   // use
   mod use_layer;
   mod use_basic;
+  mod use_private_layers;
   #[ path = "./use_as/derive.rs" ]
   mod use_as_derive;
   #[ path = "./use_as/manual.rs" ]
@@ -50,6 +51,6 @@ mod derive
 
 }
 
-// mod trybuild_test;
+mod trybuild_test;
 
 // xxx : enable
\ No newline at end of file
diff --git a/module/core/mod_interface/tests/inc/only_test/layer_simple_only_test.rs b/module/core/mod_interface/tests/inc/only_test/layer_simple_only_test.rs
index 93b1190705..f62756f61a 100644
--- a/module/core/mod_interface/tests/inc/only_test/layer_simple_only_test.rs
+++ b/module/core/mod_interface/tests/inc/only_test/layer_simple_only_test.rs
@@ -7,6 +7,12 @@ tests_impls!
   fn basic()
   {
 
+    /* test.case( "layers themself" ); */
+    {
+      a_id!( own::layer_a::layer_a_own(), true );
+      a_id!( own::layer_b::layer_b_own(), true );
+    }
+
     /* test.case( "root" ); */
     {
       a_id!( layer_a::layer_a_own(), true );
diff --git a/module/core/mod_interface/tests/inc/trybuild_test.rs b/module/core/mod_interface/tests/inc/trybuild_test.rs
index 5acc2a4f29..f5dbbbaece 100644
--- a/module/core/mod_interface/tests/inc/trybuild_test.rs
+++ b/module/core/mod_interface/tests/inc/trybuild_test.rs
@@ -5,6 +5,8 @@ use super::*;
 
 // #[ cfg_attr( feature = "enabled", module_mod_interface ) ]
 
+// xxx : qqq : enable it
+
 // #[ cfg( module_mod_interface ) ]
 // #[ cfg( module_is_terminal ) ]
 #[ test_tools::nightly ]
@@ -12,50 +14,49 @@ use super::*;
 fn trybuild_tests()
 {
   // qqq : fix test : if run its test with --target-dir flag it's fall (for example : cargo test --target-dir C:\foo\bar )
-  // // use test_tools::dependency::trybuild;
-  // println!( "current_dir : {:?}", std::env::current_dir().unwrap() );
-  // // let t = trybuild::TestCases::new();
-  // let t = test_tools::compiletime::TestCases::new();
-  // 
-  // let current_exe_path = std::env::current_exe().expect( "No such file or directory" );
-  // 
-  // let exe_directory = dbg!(current_exe_path.parent().expect("No such file or directory"));
-  // fn find_workspace_root( start_path : &std::path::Path ) -> Option< &std::path::Path >
-  // {
-  //   start_path
-  //   .ancestors()
-  //   .find( |path| path.join( "Cargo.toml" ).exists() )
-  // }
-  // 
-  // let workspace_root = find_workspace_root( exe_directory ).expect( "No such file or directory" );
-  // let current_dir = workspace_root.join( "module/core/mod_interface" );
-  // 
-  // // micro module
-  // 
-  // t.pass( current_dir.join( "tests/inc/derive/micro_modules/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/micro_modules_two/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/micro_modules_two_joined/trybuild.rs" ) );
-  // 
-  // // layer
-  // 
-  // t.pass( current_dir.join( "tests/inc/derive/layer/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/layer_have_layer/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/layer_have_layer_separate_use/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/layer_have_layer_separate_use_two/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/layer_have_layer_cfg/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/layer_use_cfg/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/layer_have_mod_cfg/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/layer_use_macro/trybuild.rs" ) );
-  // 
-  // // use
-  // 
-  // t.pass( current_dir.join( "tests/inc/derive/use_basic/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/use_layer/trybuild.rs" ) );
-  // t.pass( current_dir.join( "tests/inc/derive/use_as/trybuild.rs" ) );
-  // 
-  // // attr
-  // 
-  // t.pass( current_dir.join( "tests/inc/derive/attr_debug/trybuild.rs" ) );
+  // use test_tools::dependency::trybuild;
+  println!( "current_dir : {:?}", std::env::current_dir().unwrap() );
+  let t = test_tools::compiletime::TestCases::new();
+
+  let current_exe_path = std::env::current_exe().expect( "No such file or directory" );
+
+  let exe_directory = dbg!(current_exe_path.parent().expect("No such file or directory"));
+  fn find_workspace_root( start_path : &std::path::Path ) -> Option< &std::path::Path >
+  {
+    start_path
+    .ancestors()
+    .find( |path| path.join( "Cargo.toml" ).exists() )
+  }
+
+  let workspace_root = find_workspace_root( exe_directory ).expect( "No such file or directory" );
+  let current_dir = workspace_root.join( "module/core/mod_interface" );
+
+  // micro module
+
+  t.pass( current_dir.join( "tests/inc/derive/micro_modules/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/micro_modules_two/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/micro_modules_two_joined/trybuild.rs" ) );
+
+  // layer
+
+  t.pass( current_dir.join( "tests/inc/derive/layer/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/layer_have_layer/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/layer_have_layer_separate_use/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/layer_have_layer_separate_use_two/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/layer_have_layer_cfg/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/layer_use_cfg/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/layer_have_mod_cfg/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/layer_use_macro/trybuild.rs" ) );
+
+  // use
+
+  t.pass( current_dir.join( "tests/inc/derive/use_basic/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/use_layer/trybuild.rs" ) );
+  t.pass( current_dir.join( "tests/inc/derive/use_as/trybuild.rs" ) );
+
+  // attr
+
+  t.pass( current_dir.join( "tests/inc/derive/attr_debug/trybuild.rs" ) );
 
   //
 }
@@ -69,29 +70,28 @@ only_for_terminal_module!
   fn cta_trybuild_tests()
   {
     // qqq : fix test : if run its test with --target-dir flag it's fall (for example : cargo test --target-dir C:\foo\bar )
-    // use test_tools::dependency::trybuild;
-    // println!( "current_dir : {:?}", std::env::current_dir().unwrap() );
-    // // let t = trybuild::TestCases::new();
-    // let t = test_tools::compiletime::TestCases::new();
-    // 
-    // let current_exe_path = std::env::current_exe().expect( "No such file or directory" );
-    // 
-    // let exe_directory = current_exe_path.parent().expect( "No such file or directory" );
-    // fn find_workspace_root( start_path : &std::path::Path ) -> Option< &std::path::Path >
-    // {
-    //   start_path
-    //   .ancestors()
-    //   .find( |path| path.join( "Cargo.toml" ).exists() )
-    // }
-    // 
-    // let workspace_root = find_workspace_root( exe_directory ).expect( "No such file or directory" );
-    // let current_dir = workspace_root.join( "module/core/mod_interface" );
-    // 
-    // t.compile_fail( current_dir.join( "tests/inc/derive/micro_modules_bad_vis/trybuild.rs" ) );
-    // t.compile_fail( current_dir.join( "tests/inc/derive/micro_modules_unknown_vis/trybuild.rs" ) );
-    // t.compile_fail( current_dir.join( "tests/inc/derive/layer_bad_vis/trybuild.rs" ) );
-    // t.compile_fail( current_dir.join( "tests/inc/derive/layer_unknown_vis/trybuild.rs" ) );
-    // t.compile_fail( current_dir.join( "tests/inc/derive/use_bad_vis/trybuild.rs" ) );
-    // t.compile_fail( current_dir.join( "tests/inc/derive/use_unknown_vis/trybuild.rs" ) );
+    use test_tools::dependency::trybuild;
+    println!( "current_dir : {:?}", std::env::current_dir().unwrap() );
+    let t = test_tools::compiletime::TestCases::new();
+
+    let current_exe_path = std::env::current_exe().expect( "No such file or directory" );
+
+    let exe_directory = current_exe_path.parent().expect( "No such file or directory" );
+    fn find_workspace_root( start_path : &std::path::Path ) -> Option< &std::path::Path >
+    {
+      start_path
+      .ancestors()
+      .find( |path| path.join( "Cargo.toml" ).exists() )
+    }
+
+    let workspace_root = find_workspace_root( exe_directory ).expect( "No such file or directory" );
+    let current_dir = workspace_root.join( "module/core/mod_interface" );
+
+    t.compile_fail( current_dir.join( "tests/inc/derive/micro_modules_bad_vis/trybuild.rs" ) );
+    t.compile_fail( current_dir.join( "tests/inc/derive/micro_modules_unknown_vis/trybuild.rs" ) );
+    t.compile_fail( current_dir.join( "tests/inc/derive/layer_bad_vis/trybuild.rs" ) );
+    t.compile_fail( current_dir.join( "tests/inc/derive/layer_unknown_vis/trybuild.rs" ) );
+    t.compile_fail( current_dir.join( "tests/inc/derive/use_bad_vis/trybuild.rs" ) );
+    t.compile_fail( current_dir.join( "tests/inc/derive/use_unknown_vis/trybuild.rs" ) );
   }
 }
diff --git a/module/core/mod_interface/tests/smoke_test.rs b/module/core/mod_interface/tests/smoke_test.rs
index 828e9b016b..d826b0e72a 100644
--- a/module/core/mod_interface/tests/smoke_test.rs
+++ b/module/core/mod_interface/tests/smoke_test.rs
@@ -1,4 +1,4 @@
-
+//! Smoke tests
 
 #[ test ]
 fn local_smoke_test()
@@ -6,7 +6,6 @@ fn local_smoke_test()
   ::test_tools::smoke_test_for_local_run();
 }
 
-
 #[ test ]
 fn published_smoke_test()
 {
diff --git a/module/core/mod_interface/tests/tests.rs b/module/core/mod_interface/tests/tests.rs
index 33120affda..7736531699 100644
--- a/module/core/mod_interface/tests/tests.rs
+++ b/module/core/mod_interface/tests/tests.rs
@@ -1,3 +1,5 @@
+//! Main tests
+#![ allow( unused_imports ) ]
 
 ///  A struct for testing purpose.
 #[ derive( Debug, PartialEq ) ]
@@ -5,9 +7,7 @@ pub struct CrateStructForTesting1
 {
 }
 
-#[ allow( unused_imports ) ]
 use ::mod_interface as the_module;
-#[ allow( unused_imports ) ]
 use test_tools::exposed::*;
 #[ path="../../../../module/step/meta/src/module/terminal.rs" ]
 mod terminal;
diff --git a/module/core/mod_interface_meta/src/impls.rs b/module/core/mod_interface_meta/src/impls.rs
index 58fec18e93..84fd04d881 100644
--- a/module/core/mod_interface_meta/src/impls.rs
+++ b/module/core/mod_interface_meta/src/impls.rs
@@ -204,6 +204,16 @@ mod private
       pub use #adjsuted_path::orphan::*;
     });
 
+    // export layer as own field of current layer
+    let prefixed_with_super_maybe = path.prefixed_with_super_maybe();
+    c.clauses_map.get_mut( &VisOwn::Kind() ).unwrap().push( qt!
+    {
+      #[ doc( inline ) ]
+      #[ allow( unused_imports ) ]
+      #attrs1
+      pub use #prefixed_with_super_maybe;
+    });
+
     c.clauses_map.get_mut( &VisExposed::Kind() ).unwrap().push( qt!
     {
       #[ doc( inline ) ]
@@ -365,6 +375,16 @@ mod private
       pub use __all__::#path::orphan::*;
     });
 
+    // export layer as own field of current layer
+    // let prefixed_with_super_maybe = path.prefixed_with_super_maybe();
+    c.clauses_map.get_mut( &VisOwn::Kind() ).unwrap().push( qt!
+    {
+      #[ doc( inline ) ]
+      #[ allow( unused_imports ) ]
+      #attrs1
+      pub use super::#path;
+    });
+
     c.clauses_map.get_mut( &VisExposed::Kind() ).unwrap().push( qt!
     {
       #[ doc( inline ) ]
diff --git a/module/core/mod_interface_meta/src/use_tree.rs b/module/core/mod_interface_meta/src/use_tree.rs
index de6805dd90..2191171530 100644
--- a/module/core/mod_interface_meta/src/use_tree.rs
+++ b/module/core/mod_interface_meta/src/use_tree.rs
@@ -24,12 +24,12 @@ mod private
 
     /// Is adding prefix to the tree path required?
     /// Add `super::private::` to path unless it starts from `::` or `super` or `crate`.
-    pub fn prefix_is_needed( &self ) -> bool
+    pub fn private_prefix_is_needed( &self ) -> bool
     {
       use syn::UseTree::*;
 
-      // println!( "prefix_is_needed : {:?}", self );
-      // println!( "prefix_is_needed : self.leading_colon : {:?}", self.leading_colon );
+      // println!( "private_prefix_is_needed : {:?}", self );
+      // println!( "private_prefix_is_needed : self.leading_colon : {:?}", self.leading_colon );
 
       if self.leading_colon.is_some()
       {
@@ -105,47 +105,12 @@ mod private
       Ok( path )
     }
 
-//     /// Adjusted path.
-//     /// Add `super::private::` to path unless it starts from `::` or `super` or `crate`.
-//     pub fn adjsuted_implicit_path( &self ) -> syn::Result< syn::punctuated::Punctuated< syn::Ident, Token![::] > >
-//     {
-//       // use syn::UseTree::*;
-//       let pure_path = self.pure_path()?;
-//       if self.prefix_is_needed()
-//       {
-//         Ok( parse_qt!{ super::private::#pure_path } )
-//       }
-//       else
-//       {
-//         Ok( pure_path )
-//       }
-//     }
-//
-//     /// Adjusted path.
-//     /// Add `super::private::` to path unless it starts from `::` or `super` or `crate`.
-//     // pub fn adjsuted_explicit_path( &self ) -> syn::UseTree
-//     pub fn adjsuted_explicit_path( &self ) -> Self
-//     {
-//       // use syn::UseTree::*;
-//       if self.prefix_is_needed()
-//       {
-//         let mut clone = self.clone();
-//         let tree = parse_qt!{ super::private::#self };
-//         clone.tree = tree;
-//         clone
-//       }
-//       else
-//       {
-//         self.clone()
-//       }
-//     }
-
     /// Prefix path with __all__ if it's appropriate.
     pub fn prefixed_with_all( &self ) -> Self
     {
 
       // use syn::UseTree::*;
-      if self.prefix_is_needed()
+      if self.private_prefix_is_needed()
       {
         let mut clone = self.clone();
         let tree = parse_qt!{ __all__::#self };
@@ -159,6 +124,25 @@ mod private
 
     }
 
+    /// Prefix path with `super::` if it's appropriate to avoid "re-export of crate public `child`" problem.
+    pub fn prefixed_with_super_maybe( &self ) -> Self
+    {
+
+      // use syn::UseTree::*;
+      if self.private_prefix_is_needed()
+      {
+        let mut clone = self.clone();
+        let tree = parse_qt!{ super::#self };
+        clone.tree = tree;
+        clone
+      }
+      else
+      {
+        self.clone()
+      }
+
+    }
+
   }
 
   impl syn::parse::Parse for UseTree
diff --git a/module/core/test_tools/Cargo.toml b/module/core/test_tools/Cargo.toml
index 6d30222997..f1e7576436 100644
--- a/module/core/test_tools/Cargo.toml
+++ b/module/core/test_tools/Cargo.toml
@@ -24,13 +24,15 @@ workspace = true
 features = [ "full" ]
 all-features = false
 
-
-
 # = features
 
 [features]
-default = [ "enabled" ]
-full = [ "enabled" ]
+default = [
+  "enabled",
+  # "standalone",
+  "normal",
+]
+full = [ "default" ]
 no_std = [
   # "error_tools/no_std",
   # "meta_tools/no_std",
@@ -53,39 +55,76 @@ use_alloc = [
   # "former_stable/use_alloc",
 ]
 enabled = [
-  "error_tools/enabled",
-  "meta_tools/enabled",
-  "mem_tools/enabled",
-  "typing_tools/enabled",
-  "data_type/enabled",
-  "diagnostics_tools/enabled",
-  "process_tools/enabled",
-  "collection_tools/enabled",
+  # "error_tools/enabled",
+  # "meta_tools/enabled",
+  # "mem_tools/enabled",
+  # "typing_tools/enabled",
+  # "data_type/enabled",
+  # "diagnostics_tools/enabled",
+  # "process_tools/enabled",
+  # "collection_tools/enabled",
 ]
 # nightly = [ "typing_tools/nightly" ]
 
+normal = [
+  "dep:error_tools",
+  "dep:collection_tools",
+  "dep:meta_tools",
+  "dep:mem_tools",
+  "dep:typing_tools",
+  "dep:diagnostics_tools",
+  "dep:process_tools",
+]
+standalone = [
+  "standalone_error_tools",
+  "standalone_collection_tools",
+
+  "dep:meta_tools",
+  "dep:mem_tools",
+  "dep:typing_tools",
+  "dep:diagnostics_tools",
+  "dep:process_tools",
+]
+standalone_error_tools = [ "dep:anyhow", "dep:thiserror", "error_typed", "error_untyped" ]
+standalone_collection_tools = [ "dep:hashbrown", "collection_constructors", "collection_into_constructors" ]
+
+# error_tools
+error_typed = []
+error_untyped = []
+# collection_tools
+collection_constructors = []
+collection_into_constructors = []
+
 [dependencies]
 
 ## external
 
-paste = "~1.0" # zzz : remove laster
+# paste = "~1.0" # zzz : remove later
 rustversion = "~1.0"
-# anyhow = "~1.0"
 num-traits = "~0.2"
 trybuild = { version = "1.0.85", features = [ "diff" ] }
 rand = "0.8.5"
 
 ## internal
 
-error_tools = { workspace = true, features = [ "full" ] }
-meta_tools = { workspace = true, features = [ "full" ] }
-mem_tools = { workspace = true, features = [ "full" ] }
-typing_tools = { workspace = true, features = [ "full" ] }
-data_type = { workspace = true, features = [ "full" ] }
-diagnostics_tools = { workspace = true, features = [ "full" ] }
-process_tools = { workspace = true, features = [ "full" ] }
-collection_tools = { workspace = true, features = [ "full" ] }
+error_tools = { workspace = true, features = [ "full" ], optional = true }
+collection_tools = { workspace = true, features = [ "full" ], optional = true }
+
+meta_tools = { workspace = true, features = [ "full" ], optional = true }
+mem_tools = { workspace = true, features = [ "full" ], optional = true }
+typing_tools = { workspace = true, features = [ "full" ], optional = true }
+diagnostics_tools = { workspace = true, features = [ "full" ], optional = true }
+process_tools = { workspace = true, features = [ "full" ], optional = true }
+
 # former_stable = { workspace = true, features = [ "full" ] }
 
+## transient
+
+# error_tools
+anyhow = { workspace = true, optional = true }
+thiserror = { workspace = true, optional = true }
+# collection_tools
+hashbrown = { workspace = true, optional = true }
+
 [build-dependencies]
 rustc_version = "0.4"
diff --git a/module/core/test_tools/src/lib.rs b/module/core/test_tools/src/lib.rs
index f9870e775e..ced13dc4d8 100644
--- a/module/core/test_tools/src/lib.rs
+++ b/module/core/test_tools/src/lib.rs
@@ -6,43 +6,34 @@
 
 /// Namespace with dependencies.
 
+#[ allow( unused_imports ) ]
 #[ cfg( feature = "enabled" ) ]
 pub mod dependency
 {
 
-  // zzz : exclude later
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::paste;
+  // // zzz : exclude later
+  // #[ doc( inline ) ]
+  // pub use ::paste;
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   pub use ::trybuild;
   #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
   pub use ::rustversion;
 
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::error_tools;
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::meta_tools;
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::mem_tools;
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::typing_tools;
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::num_traits;
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::diagnostics_tools;
-
-  #[ doc( inline ) ]
-  #[ allow( unused_imports ) ]
-  pub use ::process_tools;
+  // #[ doc( inline ) ]
+  // pub use ::error_tools;
+//   #[ doc( inline ) ]
+//   pub use ::meta_tools;
+//   #[ doc( inline ) ]
+//   pub use ::mem_tools;
+//   #[ doc( inline ) ]
+//   pub use ::typing_tools;
+//   #[ doc( inline ) ]
+//   pub use ::num_traits;
+//   #[ doc( inline ) ]
+//   pub use ::diagnostics_tools;
+//
+//   #[ doc( inline ) ]
+//   pub use ::process_tools;
 
   // #[ doc( inline ) ]
   // #[ allow( unused_imports ) ]
@@ -54,56 +45,168 @@ mod private {}
 
 //
 
-#[ cfg( feature = "enabled" ) ]
+// #[ cfg( feature = "enabled" ) ]
+// // #[ cfg( not( feature = "no_std" ) ) ]
+// ::meta_tools::mod_interface!
+// {
+//   // #![ debug ]
+//
+//   own use super::dependency::*;
+//
+//   layer test;
+//
+//   // xxx : comment out
+//   use super::exposed::meta;
+//   use super::exposed::mem;
+//   use super::exposed::typing;
+//   use super::exposed::dt;
+//   use super::exposed::diagnostics;
+//   use super::exposed::collection;
+//   // use super::exposed::process;
+//
+//   // prelude use ::rustversion::{ nightly, stable };
+//
+//   // // xxx : eliminate need to do such things, putting itself to proper category
+//   // exposed use super::test::compiletime;
+//   // exposed use super::test::helper;
+//   // exposed use super::test::smoke_test;
+//
+//   prelude use ::meta_tools as meta;
+//   prelude use ::mem_tools as mem;
+//   prelude use ::typing_tools as typing;
+//   prelude use ::data_type as dt;
+//   prelude use ::diagnostics_tools as diagnostics;
+//   prelude use ::collection_tools as collection;
+//   // prelude use ::process_tools as process;
+//
+//   use ::collection_tools; // xxx : do that for all dependencies
+//
+//   prelude use ::meta_tools::
+//   {
+//     impls,
+//     index,
+//     tests_impls,
+//     tests_impls_optional,
+//     tests_index,
+//   };
+//
+//   prelude use ::typing_tools::{ implements };
+//
+// }
+
+// xxx : use module namespaces
+// #[ cfg( feature = "enabled" ) ]
 // #[ cfg( not( feature = "no_std" ) ) ]
-::meta_tools::mod_interface!
+// pub use test::{ compiletime, helper, smoke_test };
+
+#[ cfg( feature = "enabled" ) ]
+pub mod test;
+
+/// Error tools.
+#[ cfg( feature = "standalone" ) ]
+#[ path = "../../../core/error_tools/src/error/mod.rs" ]
+pub mod error;
+#[ cfg( feature = "standalone" ) ]
+pub use error as error_tools;
+
+/// Collection tools.
+#[ cfg( feature = "standalone" ) ]
+#[ path = "../../../core/collection_tools/src/collection/mod.rs" ]
+pub mod collection;
+#[ cfg( feature = "standalone" ) ]
+pub use collection as collection_tools;
+
+#[ cfg( feature = "enabled" ) ]
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod own
 {
-  // #![ debug ]
+  use super::*;
 
-  own use super::dependency::*;
+  #[ doc( inline ) ]
+  pub use orphan::*;
 
-  layer test;
+  #[ doc( inline ) ]
+  pub use test::own::*;
 
-  // xxx : comment out
-  use super::exposed::meta;
-  use super::exposed::mem;
-  use super::exposed::typing;
-  use super::exposed::dt;
-  use super::exposed::diagnostics;
-  use super::exposed::collection;
-  // use super::exposed::process;
+  #[ doc( inline ) ]
+  pub use
+  {
+    error_tools::orphan::*,
+    collection_tools::orphan::*,
+    // meta_tools::orphan::*,
+    mem_tools::orphan::*,
+    typing_tools::orphan::*,
+    diagnostics_tools::orphan::*,
+  };
 
-  // prelude use ::rustversion::{ nightly, stable };
+}
 
-  // // xxx : eliminate need to do such things, putting itself to proper category
-  // exposed use super::test::compiletime;
-  // exposed use super::test::helper;
-  // exposed use super::test::smoke_test;
+/// Shared with parent namespace of the module
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use exposed::*;
 
-  prelude use ::meta_tools as meta;
-  prelude use ::mem_tools as mem;
-  prelude use ::typing_tools as typing;
-  prelude use ::data_type as dt;
-  prelude use ::diagnostics_tools as diagnostics;
-  prelude use ::collection_tools as collection;
-  // prelude use ::process_tools as process;
+  #[ doc( inline ) ]
+  pub use test::orphan::*;
+
+}
+
+/// Exposed namespace of the module.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
 
-  use ::collection_tools; // xxx : do that for all dependencies
+  #[ doc( inline ) ]
+  pub use test::exposed::*;
 
-  prelude use ::meta_tools::
+  #[ doc( inline ) ]
+  pub use
   {
-    impls,
-    index,
-    tests_impls,
-    tests_impls_optional,
-    tests_index,
+    error_tools::exposed::*,
+    collection_tools::exposed::*,
+    // meta_tools::exposed::*,
+    mem_tools::exposed::*,
+    typing_tools::exposed::*,
+    diagnostics_tools::exposed::*,
   };
 
-  prelude use ::typing_tools::{ implements };
-
 }
 
-// xxx : use module namespaces
-// #[ cfg( feature = "enabled" ) ]
-// #[ cfg( not( feature = "no_std" ) ) ]
-// pub use test::{ compiletime, helper, smoke_test };
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use test::prelude::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+    error_tools::prelude::*,
+    collection_tools::prelude::*,
+    // meta_tools::prelude::*,
+    mem_tools::prelude::*,
+    typing_tools::prelude::*,
+    diagnostics_tools::prelude::*,
+  };
+
+}
diff --git a/module/core/test_tools/src/test/asset.rs b/module/core/test_tools/src/test/asset.rs
index 410707ed36..e206fc8c0f 100644
--- a/module/core/test_tools/src/test/asset.rs
+++ b/module/core/test_tools/src/test/asset.rs
@@ -34,14 +34,73 @@ mod private
 }
 
 
+// //
+// // #[ cfg( not( feature = "no_std" ) ) ]
+// crate::mod_interface!
+// {
 //
-// #[ cfg( not( feature = "no_std" ) ) ]
-crate::mod_interface!
+//   // exposed use super;
+//   exposed use super::super::asset;
+//
+//   // own use path_to_exe;
+//
+// }
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod own
 {
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
+
+}
+
+/// Shared with parent namespace of the module
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use exposed::*;
 
-  // exposed use super;
-  exposed use super::super::asset;
+  pub use super::super::asset;
+
+}
+
+/// Exposed namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
+
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
 
-  // own use path_to_exe;
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
 
 }
diff --git a/module/core/test_tools/src/test/compiletime.rs b/module/core/test_tools/src/test/compiletime.rs
index 4f29ec998e..7ea5edf31f 100644
--- a/module/core/test_tools/src/test/compiletime.rs
+++ b/module/core/test_tools/src/test/compiletime.rs
@@ -73,14 +73,74 @@ mod private
 //   }
 // }
 
-crate::mod_interface!
+// crate::mod_interface!
+// {
+//   // #![ debug ]
+//   // xxx : make it working
+//   // exposed use super;
+//   exposed use super::super::compiletime;
+//   own use
+//   {
+//     *
+//   };
+// }
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod own
 {
-  // #![ debug ]
-  // xxx : make it working
-  // exposed use super;
-  exposed use super::super::compiletime;
-  own use
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
   {
-    *
+    private::*,
   };
+
+}
+
+/// Shared with parent namespace of the module
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use exposed::*;
+
+  pub use super::super::compiletime;
+
+}
+
+/// Exposed namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
+
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
+
 }
diff --git a/module/core/test_tools/src/test/helper.rs b/module/core/test_tools/src/test/helper.rs
index 49675e2ada..4a97b134da 100644
--- a/module/core/test_tools/src/test/helper.rs
+++ b/module/core/test_tools/src/test/helper.rs
@@ -75,16 +75,78 @@ mod private
   pub use doc_file_test;
 }
 
-crate::mod_interface!
+// crate::mod_interface!
+// {
+//   // xxx
+//   // #![ debug ]
+//   // exposed use super;
+//   exposed use super::super::helper;
+//
+//   prelude use
+//   {
+//     num,
+//     doc_file_test,
+//   };
+// }
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod own
 {
-  // xxx
-  // #![ debug ]
-  // exposed use super;
-  exposed use super::super::helper;
+  use super::*;
 
-  prelude use
+  #[ doc( inline ) ]
+  pub use
   {
-    num,
-    doc_file_test,
+    private::*,
   };
+
+}
+
+/// Shared with parent namespace of the module
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use exposed::*;
+
+  pub use super::super::helper;
+
+}
+
+/// Exposed namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+    private::num,
+    private::doc_file_test,
+  };
+
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
+
 }
diff --git a/module/core/test_tools/src/test/mod.rs b/module/core/test_tools/src/test/mod.rs
index 158406fbd1..0d62f6e9d2 100644
--- a/module/core/test_tools/src/test/mod.rs
+++ b/module/core/test_tools/src/test/mod.rs
@@ -5,12 +5,107 @@
 
 mod private {}
 
-// #[ cfg( not( feature = "no_std" ) ) ]
-crate::mod_interface!
+// // #[ cfg( not( feature = "no_std" ) ) ]
+// crate::mod_interface!
+// {
+//   layer asset;
+//   layer compiletime;
+//   layer helper;
+//   layer smoke_test;
+//   layer version;
+// }
+
+pub mod asset;
+pub mod compiletime;
+pub mod helper;
+pub mod smoke_test;
+pub mod version;
+
+#[ cfg( feature = "enabled" ) ]
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod own
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use orphan::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+    asset::orphan::*,
+    compiletime::orphan::*,
+    helper::orphan::*,
+    smoke_test::orphan::*,
+    version::orphan::*,
+  };
+
+}
+
+/// Shared with parent namespace of the module
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod orphan
 {
-  layer asset;
-  layer compiletime;
-  layer helper;
-  layer smoke_test;
-  layer version;
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use exposed::*;
+
+}
+
+/// Exposed namespace of the module.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+    asset::exposed::*,
+    compiletime::exposed::*,
+    helper::exposed::*,
+    smoke_test::exposed::*,
+    version::exposed::*,
+  };
+
+  pub use meta_tools::
+  {
+    impls,
+    index,
+    tests_impls,
+    tests_impls_optional,
+    tests_index,
+  };
+
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ cfg( feature = "enabled" ) ]
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+    asset::prelude::*,
+    compiletime::prelude::*,
+    helper::prelude::*,
+    smoke_test::prelude::*,
+    version::prelude::*,
+  };
+
 }
diff --git a/module/core/test_tools/src/test/smoke_test.rs b/module/core/test_tools/src/test/smoke_test.rs
index 34ebd2f55f..0074d4f090 100644
--- a/module/core/test_tools/src/test/smoke_test.rs
+++ b/module/core/test_tools/src/test/smoke_test.rs
@@ -11,8 +11,9 @@
 /// Internal namespace.
 mod private
 {
+  #[ allow( unused_imports ) ]
   use crate::*;
-  use dependency::process_tools::environment;
+  use process_tools::environment;
   // zzz : comment out
   // pub mod environment
   // {
@@ -316,17 +317,83 @@ mod private
 }
 
 
+// //
+// crate::mod_interface!
+// {
 //
-crate::mod_interface!
+//   // exposed use super;
+//   exposed use super::super::smoke_test;
+//
+//   exposed use SmokeModuleTest;
+//   exposed use smoke_test_run;
+//   exposed use smoke_tests_run;
+//   exposed use smoke_test_for_local_run;
+//   exposed use smoke_test_for_published_run;
+//
+// }
+
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod own
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+    private::*,
+  };
+
+}
+
+/// Shared with parent namespace of the module
+#[ allow( unused_imports ) ]
+pub mod orphan
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use exposed::*;
+
+  pub use super::super::smoke_test;
+
+}
+
+/// Exposed namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod exposed
 {
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
 
-  // exposed use super;
-  exposed use super::super::smoke_test;
+  #[ doc( inline ) ]
+  pub use private::
+  {
+    SmokeModuleTest,
+    smoke_test_run,
+    smoke_tests_run,
+    smoke_test_for_local_run,
+    smoke_test_for_published_run,
+  };
+
+}
 
-  exposed use SmokeModuleTest;
-  exposed use smoke_test_run;
-  exposed use smoke_tests_run;
-  exposed use smoke_test_for_local_run;
-  exposed use smoke_test_for_published_run;
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
 
 }
diff --git a/module/core/test_tools/src/test/version.rs b/module/core/test_tools/src/test/version.rs
index 7737b5b456..8cdc5cbbc8 100644
--- a/module/core/test_tools/src/test/version.rs
+++ b/module/core/test_tools/src/test/version.rs
@@ -10,14 +10,73 @@ mod private
 }
 
 
+// //
+// // #[ cfg( not( feature = "no_std" ) ) ]
+// crate::mod_interface!
+// {
 //
-// #[ cfg( not( feature = "no_std" ) ) ]
-crate::mod_interface!
+//   // exposed use super;
+//   exposed use super::super::version;
+//
+//   prelude use ::rustversion::{ nightly, stable };
+//
+// }
+
+
+#[ doc( inline ) ]
+#[ allow( unused_imports ) ]
+pub use own::*;
+
+/// Own namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod own
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use
+  {
+    private::*,
+  };
+
+}
+
+/// Shared with parent namespace of the module
+#[ allow( unused_imports ) ]
+pub mod orphan
 {
+  use super::*;
 
-  // exposed use super;
-  exposed use super::super::version;
+  #[ doc( inline ) ]
+  pub use exposed::*;
+
+  pub use super::super::version;
+
+}
+
+/// Exposed namespace of the module.
+#[ allow( unused_imports ) ]
+pub mod exposed
+{
+  use super::*;
+
+  #[ doc( inline ) ]
+  pub use prelude::*;
+
+  #[ doc( inline ) ]
+  pub use rustversion::{ nightly, stable };
+
+}
+
+/// Prelude to use essentials: `use my_module::prelude::*`.
+#[ allow( unused_imports ) ]
+pub mod prelude
+{
+  use super::*;
 
-  prelude use ::rustversion::{ nightly, stable };
+  #[ doc( inline ) ]
+  pub use
+  {
+  };
 
 }
diff --git a/module/core/test_tools/tests/inc/basic_test.rs b/module/core/test_tools/tests/inc/basic_test.rs
index 8e631611f4..9b1133fb91 100644
--- a/module/core/test_tools/tests/inc/basic_test.rs
+++ b/module/core/test_tools/tests/inc/basic_test.rs
@@ -15,7 +15,6 @@
 use super::*;
 use ::test_tools as the_module;
 
-
 #[ cfg( feature = "enabled" ) ]
 #[ cfg( not( feature = "no_std" ) ) ]
 the_module::tests_impls!
diff --git a/module/core/wtools/Cargo.toml b/module/core/wtools/Cargo.toml
index 4d2e2f1f29..c8d108f307 100644
--- a/module/core/wtools/Cargo.toml
+++ b/module/core/wtools/Cargo.toml
@@ -58,7 +58,7 @@ meta_default = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  # "meta_constructors",
   "meta_idents_concat",
 ]
 meta_full = [
@@ -68,7 +68,7 @@ meta_full = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  # "meta_constructors",
   "meta_idents_concat",
 ]
 # meta_use_std = [ "meta", "meta_tools/use_std" ]
@@ -79,7 +79,7 @@ meta_for_each = [ "meta", "meta_tools/meta_for_each" ]
 meta_impls_index = [ "meta", "meta_tools/meta_impls_index" ]
 meta_mod_interface = [ "meta" ]
 # meta_mod_interface = [ "meta", "meta_tools/mod_interface" ]
-meta_constructors = [ "meta", "meta_tools/meta_constructors" ]
+# meta_constructors = [ "meta", "meta_tools/meta_constructors" ]
 meta_idents_concat = [ "meta", "meta_tools/meta_idents_concat" ]
 # meta_former = [ "meta", "meta_tools/former" ]
 # meta_options = [ "meta", "meta_tools/options" ]
diff --git a/module/move/optimization_tools/Cargo.toml b/module/move/optimization_tools/Cargo.toml
index de8500b846..af2f73c222 100644
--- a/module/move/optimization_tools/Cargo.toml
+++ b/module/move/optimization_tools/Cargo.toml
@@ -40,7 +40,9 @@ lp_parse = [ "dep:exmex" ]
 derive_tools = { workspace = true, features = [ "derive_more", "full", "strum" ] }
 deterministic_rand = { workspace = true, features = [ "default" ] }
 iter_tools = { workspace = true, features = [ "default" ] }
-meta_tools = { workspace = true, features = [ "meta_constructors" ] }
+# meta_tools = { workspace = true, features = [ "meta_constructors" ] }
+meta_tools = { workspace = true, features = [] }
+collection_tools = { workspace = true } # qqq : use intead of meta_tools
 error_tools = { workspace = true, features = ["default"] }
 env_logger = "0.10.1"
 log = "0.4.20"
diff --git a/module/move/wca/src/ca/executor/executor.rs b/module/move/wca/src/ca/executor/executor.rs
index 224aacd489..22e44fc19b 100644
--- a/module/move/wca/src/ca/executor/executor.rs
+++ b/module/move/wca/src/ca/executor/executor.rs
@@ -3,7 +3,7 @@ mod private
   use crate::*;
 
   // use wtools::error::Result;
-  use error::return_err;
+  // use error::return_err;
   use ca::help::{ HelpGeneratorOptions, generate_help_content, LevelOfDetail };
 
   // aaa : for Bohdan : how is it useful? where is it used?
@@ -122,7 +122,7 @@ mod private
         let commands = dictionary.search( name.strip_prefix( '.' ).unwrap_or( name ) );
         if commands.is_empty()
         {
-          return_err!( "Not found command that starts with `.{}`.", name );
+          error::untyped::return_err!( "Not found command that starts with `.{}`.", name );
         }
         let generator_args = HelpGeneratorOptions::former()
         .command_prefix( "." )
@@ -151,10 +151,10 @@ mod private
         }
         else
         {
-          return_err!( "Not found command that starts with `.{}`.", name );
+          error::untyped::return_err!( "Not found command that starts with `.{}`.", name );
         }
       }
-      unexpected => return_err!( "Encountered an unrecognized internal command: `.{}`.", unexpected ),
+      unexpected => error::untyped::return_err!( "Encountered an unrecognized internal command: `.{}`.", unexpected ),
     }
 
     Ok( () )
diff --git a/module/move/wca/src/ca/grammar/types.rs b/module/move/wca/src/ca/grammar/types.rs
index d5c6e971df..2141ca335b 100644
--- a/module/move/wca/src/ca/grammar/types.rs
+++ b/module/move/wca/src/ca/grammar/types.rs
@@ -8,7 +8,7 @@ mod private
   };
   // use wtools;
   // use wtools::{ error::Result, err };
-  use error::err;
+  // use error::err;
   use iter_tools::Itertools;
 
   /// Available types that can be converted to a `Value`
@@ -186,9 +186,9 @@ mod private
       match self
       {
         Self::String => Ok( Value::String( value ) ),
-        Self::Number => value.parse().map_err( | _ | err!( "Can not parse number from `{}`", value ) ).map( Value::Number ),
+        Self::Number => value.parse().map_err( | _ | error::untyped::format_err!( "Can not parse number from `{}`", value ) ).map( Value::Number ),
         Self::Path => Ok( Value::Path( value.into() ) ),
-        Self::Bool => Ok( Value::Bool( match value.as_str() { "1" | "true" => true, "0" | "false" => false, _ => return Err( err!( "Can not parse bool from `{}`", value ) ) } ) ),
+        Self::Bool => Ok( Value::Bool( match value.as_str() { "1" | "true" => true, "0" | "false" => false, _ => return Err( error::untyped::format_err!( "Can not parse bool from `{}`", value ) ) } ) ),
         Self::List( kind, delimeter ) =>
         {
           let values = value
diff --git a/module/move/wca/src/ca/parser/parser.rs b/module/move/wca/src/ca/parser/parser.rs
index 1efe959495..4a23f24db3 100644
--- a/module/move/wca/src/ca/parser/parser.rs
+++ b/module/move/wca/src/ca/parser/parser.rs
@@ -4,7 +4,7 @@ mod private
 
   use std::collections::HashMap;
 
-  use error::{ return_err };
+  // use error::{ return_err };
 
   /// `Parser` is a struct used for parsing data.
   #[ derive( Debug ) ]
@@ -58,14 +58,14 @@ mod private
     fn parse_command( args : &[ String ] ) -> error::untyped::Result< ( ParsedCommand, usize ) >
     {
       if args.is_empty() {
-        return_err!( "Unexpected behaviour: Try to parse command without input" );
+        error::untyped::return_err!( "Unexpected behaviour: Try to parse command without input" );
       }
 
       let mut i = 0;
 
       if !Self::valid_command_name( &args[ i ] )
       {
-        return_err!( "Unexpected input: Expected a command, found: `{}`", args[ i ] );
+        error::untyped::return_err!( "Unexpected input: Expected a command, found: `{}`", args[ i ] );
       }
       let name = match args[ i ].strip_prefix( '.' ).unwrap()
       {
@@ -125,7 +125,7 @@ mod private
           // prop:
           else
           {
-            return_err!( "Unexpected input '{}': Detected a possible property key preceding the ':' character. However, no corresponding value was found.", item );
+            error::untyped::return_err!( "Unexpected input '{}': Detected a possible property key preceding the ':' character. However, no corresponding value was found.", item );
           }
         }
         // prop : value | prop :value
@@ -146,13 +146,22 @@ mod private
           // :
           else
           {
-            return_err!( "Unexpected input '{} :': Detected a possible property key preceding the ':' character. However, no corresponding value was found.", item );
+            error::untyped::return_err!
+            (
+              "Unexpected input '{} :': Detected a possible property key preceding the ':' character. However, no corresponding value was found.",
+              item,
+            );
           }
         }
 
-        else if !properties_turn { subjects.push( item.to_string() ); }
-
-        else { return_err!( "Unexpected input: Expected `command` or `property`, found: `{}`", item ); }
+        else if !properties_turn
+        {
+          subjects.push( item.to_string() );
+        }
+        else
+        {
+          error::untyped::return_err!( "Unexpected input: Expected `command` or `property`, found: `{}`", item );
+        }
         i += 1;
       }
 
diff --git a/module/move/wca/src/ca/tool/mod.rs b/module/move/wca/src/ca/tool/mod.rs
index 91290592a7..3f400c96a9 100644
--- a/module/move/wca/src/ca/tool/mod.rs
+++ b/module/move/wca/src/ca/tool/mod.rs
@@ -7,7 +7,10 @@ crate::mod_interface!
   layer table;
 
   orphan use super::super::tool;
-  orphan use ::error_tools as error;
+
+  // orphan use ::error_tools as error;
+  use ::error_tools;
+
   orphan use ::iter_tools;
 
   // use ::strs_tools as string; // xxx : check
diff --git a/module/move/wca/src/ca/tool/table.rs b/module/move/wca/src/ca/tool/table.rs
index 192caa0396..424356530b 100644
--- a/module/move/wca/src/ca/tool/table.rs
+++ b/module/move/wca/src/ca/tool/table.rs
@@ -3,7 +3,7 @@ mod private
   use crate::*;
 
   // use wtools::error::{ Result, err };
-  use error::err;
+  // use error::err;
 
   /// Represents a table composed of multiple rows.
   ///
@@ -98,7 +98,7 @@ mod private
     let table = table.into();
     if !table.validate()
     {
-      return Err( err!( "Invalid table" ) );
+      return Err( error::untyped::format_err!( "Invalid table" ) );
     }
 
     let max_lengths = max_column_lengths( &table );
diff --git a/module/move/wca/src/ca/verifier/verifier.rs b/module/move/wca/src/ca/verifier/verifier.rs
index a595521755..0202279546 100644
--- a/module/move/wca/src/ca/verifier/verifier.rs
+++ b/module/move/wca/src/ca/verifier/verifier.rs
@@ -7,7 +7,7 @@ mod private
   use std::collections::HashMap;
   use indexmap::IndexMap;
   // use wtools::{ error, error::Result, err };
-  use error::err;
+  // use error::err;
   use ca::help::{ HelpGeneratorOptions, LevelOfDetail, generate_help_content };
   // xxx
 
@@ -134,12 +134,12 @@ mod private
         {
           Some( v ) => v,
           None if *optional => continue,
-          _ => return Err( err!( "Missing not optional subject" ) ),
+          _ => return Err( error::untyped::format_err!( "Missing not optional subject" ) ),
         };
         subjects.push( value );
         current = rc_subjects_iter.next();
       }
-      if let Some( value ) = current { return Err( err!( "Can not identify a subject: `{}`", value ) ) }
+      if let Some( value ) = current { return Err( error::untyped::format_err!( "Can not identify a subject: `{}`", value ) ) }
 
       Ok( subjects )
     }
@@ -214,8 +214,10 @@ mod private
         {
           #[ cfg( feature = "on_unknown_suggest" ) ]
           if let Some( phrase ) = Self::suggest_command( dictionary, &raw_command.name )
-          { return err!( "Command not found. Maybe you mean `.{}`?", phrase ) }
-          err!( "Command not found. Please use `.` command to see the list of available commands." )
+          {
+            return error::untyped::format_err!( "Command not found. Maybe you mean `.{}`?", phrase )
+          }
+          error::untyped::format_err!( "Command not found. Please use `.` command to see the list of available commands." )
         }
       )?;
 
diff --git a/module/move/willbe/src/action/cicd_renew.rs b/module/move/willbe/src/action/cicd_renew.rs
index fdf14a1216..5814e2802c 100644
--- a/module/move/willbe/src/action/cicd_renew.rs
+++ b/module/move/willbe/src/action/cicd_renew.rs
@@ -19,7 +19,7 @@ mod private
   use error::
   {
     typed::Error,
-    err,
+    // err,
   };
 
   #[ derive( Debug, Error ) ]
@@ -42,7 +42,7 @@ mod private
 
   // qqq : for Petro : should return Report and typed error in Result
   /// Generate workflows for modules in .github/workflows directory.
-  pub fn cicd_renew( base_path : &Path ) -> Result< (), CiCdGenerateError >
+  pub fn action( base_path : &Path ) -> Result< (), CiCdGenerateError >
   {
     let workspace_cache = Workspace::try_from( CrateDir::try_from( base_path )? )?;
     let packages = workspace_cache.packages();
@@ -375,7 +375,7 @@ mod private
         return url::repo_url_extract( &url )
         .and_then( | url | url::git_info_extract( &url ).ok() )
         .map( UsernameAndRepository )
-        .ok_or_else( || err!( "Fail to parse repository url from workspace Cargo.toml"))
+        .ok_or_else( || error::untyped::format_err!( "Fail to parse repository url from workspace Cargo.toml"))
       }
       else
       {
@@ -393,7 +393,7 @@ mod private
         .and_then( | url | url::repo_url_extract( &url ) )
         .and_then( | url | url::git_info_extract( &url ).ok() )
         .map( UsernameAndRepository )
-        .ok_or_else( || err!( "Fail to extract repository url") )
+        .ok_or_else( || error::untyped::format_err!( "Fail to extract repository url") )
       }
     }
 
@@ -401,5 +401,5 @@ mod private
 
 crate::mod_interface!
 {
-  exposed use cicd_renew;
+  own use action;
 }
diff --git a/module/move/willbe/src/action/features.rs b/module/move/willbe/src/action/features.rs
index 26b8701cc2..ca7312d289 100644
--- a/module/move/willbe/src/action/features.rs
+++ b/module/move/willbe/src/action/features.rs
@@ -112,3 +112,4 @@ crate::mod_interface!
   orphan use FeaturesOptions;
   orphan use FeaturesReport;
 }
+// qqq : don't use orphan here
\ No newline at end of file
diff --git a/module/move/willbe/src/action/list.rs b/module/move/willbe/src/action/list.rs
index 6f2708217b..074189cd7f 100644
--- a/module/move/willbe/src/action/list.rs
+++ b/module/move/willbe/src/action/list.rs
@@ -13,7 +13,7 @@ mod private
   };
   use error::
   {
-    ErrWith, err,
+    ErrWith,
     untyped::{ Context, format_err },
   };
   use tool::{ TreePrinter, ListNodeReport };
@@ -39,7 +39,7 @@ mod private
       {
         "tree" => ListFormat::Tree,
         "toposort" => ListFormat::Topological,
-        e => return Err( err!( "Unknown format '{}'. Available values : [tree, toposort]", e ))
+        e => return Err( error::untyped::format_err!( "Unknown format '{}'. Available values : [tree, toposort]", e ))
       };
 
       Ok( value )
@@ -105,7 +105,7 @@ mod private
       {
         "nothing" => ListFilter::Nothing,
         "local" => ListFilter::Local,
-        e => return Err( err!( "Unknown filter '{}'. Available values : [nothing, local]", e ) )
+        e => return Err( error::untyped::format_err!( "Unknown filter '{}'. Available values : [nothing, local]", e ) )
       };
 
       Ok( value )
@@ -436,7 +436,7 @@ mod private
   /// - `Result<ListReport, (ListReport, Error)>` - A result containing the list report if successful,
   ///   or a tuple containing the list report and error if not successful.
   #[ cfg_attr( feature = "tracing", tracing::instrument ) ]
-  pub fn list( args : ListOptions )
+  pub fn list_all( args : ListOptions )
   ->
   ResultWithReport< ListReport, error::untyped::Error > // qqq : should be specific error
   // qqq : use typed error
@@ -849,5 +849,5 @@ crate::mod_interface!
   /// Contains output of a single node of the action.
   // own use ListNodeReport;
   /// List packages in workspace.
-  orphan use list;
+  orphan use list_all;
 }
diff --git a/module/move/willbe/src/action/main_header.rs b/module/move/willbe/src/action/main_header.rs
index 7c1b5af526..05ca9ec085 100644
--- a/module/move/willbe/src/action/main_header.rs
+++ b/module/move/willbe/src/action/main_header.rs
@@ -18,8 +18,8 @@ mod private
   use entity::{ PathError, WorkspaceInitError };
   use error::
   {
-    err,
-    untyped::Error,
+    // err,
+    // untyped::Error,
   };
   use workspace_md_extension::WorkspaceMdExtension;
 
@@ -86,7 +86,7 @@ mod private
   {
     /// Represents a common error.
     #[ error( "Common error: {0}" ) ]
-    Common(#[ from ] Error ),
+    Common( #[ from ] error::untyped::Error ), // qqq : rid of
     /// Represents an I/O error.
     #[ error( "I/O error: {0}" ) ]
     IO( #[ from ] std::io::Error ),
@@ -116,14 +116,14 @@ mod private
       // aaa : done
       let repository_url = workspace
       .repository_url()
-      .ok_or_else::< Error, _ >
-      ( || err!( "repo_url not found in workspace Cargo.toml" ) )?;
+      .ok_or_else::< error::untyped::Error, _ >
+      ( || error::untyped::format_err!( "repo_url not found in workspace Cargo.toml" ) )?;
 
       let master_branch = workspace.master_branch().unwrap_or( "master".into() );
       let workspace_name = workspace
       .workspace_name()
-      .ok_or_else::< Error, _ >
-      ( || err!( "workspace_name not found in workspace Cargo.toml" ) )?;
+      .ok_or_else::< error::untyped::Error, _ >
+      ( || error::untyped::format_err!( "workspace_name not found in workspace Cargo.toml" ) )?;
 
       let discord_url = workspace.discord_url();
 
@@ -193,7 +193,7 @@ mod private
   /// [![docs.rs](https://raster.shields.io/static/v1?label=docs&message=online&color=eee&logo=docsdotrs&logoColor=eee)](https://docs.rs/wtools)
   /// <!--{ generate.main_header.end }-->
   /// ```
-  pub fn readme_header_renew( crate_dir : CrateDir )
+  pub fn action( crate_dir : CrateDir )
   // -> Result< MainHeaderRenewReport, ( MainHeaderRenewReport, MainHeaderRenewError ) >
   -> ResultWithReport< MainHeaderRenewReport, MainHeaderRenewError >
   {
@@ -265,7 +265,7 @@ mod private
 crate::mod_interface!
 {
   /// Generate header.
-  orphan use readme_header_renew;
+  own use action;
   /// Report.
   orphan use MainHeaderRenewReport;
   /// Error.
diff --git a/module/move/willbe/src/action/publish_diff.rs b/module/move/willbe/src/action/publish_diff.rs
index d27920c7bc..11b1758ca8 100644
--- a/module/move/willbe/src/action/publish_diff.rs
+++ b/module/move/willbe/src/action/publish_diff.rs
@@ -105,7 +105,7 @@ mod private
     let path = AbsolutePath::try_from( o.path )?;
     let dir = CrateDir::try_from( path.clone() )?;
 
-    let list = action::list
+    let list = action::list_all
     (
       action::list::ListOptions::former()
       .path_to_manifest( dir )
diff --git a/module/move/willbe/src/action/readme_modules_headers_renew.rs b/module/move/willbe/src/action/readme_modules_headers_renew.rs
index 9b613d97fa..aeba473c74 100644
--- a/module/move/willbe/src/action/readme_modules_headers_renew.rs
+++ b/module/move/willbe/src/action/readme_modules_headers_renew.rs
@@ -20,11 +20,11 @@ mod private
   use package::Package;
   use error::
   {
-    err,
+    // err,
     untyped::
     {
       // Result,
-      Error as wError,
+      // Error as wError,
       Context,
     },
   };
@@ -101,7 +101,7 @@ mod private
   {
     /// Represents a common error.
     #[ error( "Common error: {0}" ) ]
-    Common(#[ from ] wError ),
+    Common(#[ from ] error::untyped::Error ), // qqq : rid of
     /// Represents an I/O error.
     #[ error( "I/O error: {0}" ) ]
     IO( #[ from ] std::io::Error ),
@@ -140,7 +140,7 @@ mod private
       let stability = package.stability()?;
       let module_name = package.name()?;
       let repository_url = package.repository()?
-      .ok_or_else::< wError, _ >( || err!( "Fail to find repository_url in module`s Cargo.toml" ) )?;
+      .ok_or_else::< error::untyped::Error, _ >( || error::untyped::format_err!( "Fail to find repository_url in module`s Cargo.toml" ) )?;
 
       let discord_url = package
       .discord_url()?
@@ -172,7 +172,7 @@ mod private
 
       let repo_url = url::repo_url_extract( &self.repository_url )
       .and_then( | r | url::git_info_extract( &r ).ok() )
-      .ok_or_else::< wError, _ >( || err!( "Fail to parse repository url" ) )?;
+      .ok_or_else::< error::untyped::Error, _ >( || error::untyped::format_err!( "Fail to parse repository url" ) )?;
       let example= if let Some( name ) = find_example_file
       (
         self.module_path.as_path(),
@@ -269,7 +269,7 @@ mod private
       .join
       (
         repository::readme_path( path.parent().unwrap().as_ref() )
-        // .ok_or_else::< wError, _ >( || err!( "Fail to find README.md at {}", &path ) )
+        // .ok_or_else::< error::untyped::Error, _ >( || error::untyped::format_err!( "Fail to find README.md at {}", &path ) )
         .err_with_report( &report )?
       );
 
diff --git a/module/move/willbe/src/action/workspace_renew.rs b/module/move/willbe/src/action/workspace_renew.rs
index 58e4ad61ea..05936758d9 100644
--- a/module/move/willbe/src/action/workspace_renew.rs
+++ b/module/move/willbe/src/action/workspace_renew.rs
@@ -134,7 +134,7 @@ mod private
   // qqq : for Petro : should return report
   // qqq : for Petro : should have typed error
   /// Creates workspace template
-  pub fn workspace_renew
+  pub fn action
   (
     path : &Path,
     mut template : WorkspaceTemplate,
@@ -172,6 +172,6 @@ mod private
 
 crate::mod_interface!
 {
-  exposed use workspace_renew;
+  own use action;
   orphan use WorkspaceTemplate;
 }
diff --git a/module/move/willbe/src/command/cicd_renew.rs b/module/move/willbe/src/command/cicd_renew.rs
index 50b1a8de91..c82b45b8da 100644
--- a/module/move/willbe/src/command/cicd_renew.rs
+++ b/module/move/willbe/src/command/cicd_renew.rs
@@ -10,7 +10,7 @@ mod private
   // qqq : typed error
   pub fn cicd_renew() -> error::untyped::Result< () >
   {
-    action::cicd_renew
+    action::cicd_renew::action
     (
       &std::env::current_dir()?
     )
diff --git a/module/move/willbe/src/command/list.rs b/module/move/willbe/src/command/list.rs
index c1bb086099..83e252fc65 100644
--- a/module/move/willbe/src/command/list.rs
+++ b/module/move/willbe/src/command/list.rs
@@ -80,7 +80,7 @@ mod private
     .dependency_categories( categories )
     .form();
 
-    match action::list( o )
+    match action::list_all( o )
     {
       Ok( report ) =>
       {
diff --git a/module/move/willbe/src/command/main_header.rs b/module/move/willbe/src/command/main_header.rs
index efd23e67c4..b29229e9bd 100644
--- a/module/move/willbe/src/command/main_header.rs
+++ b/module/move/willbe/src/command/main_header.rs
@@ -1,14 +1,14 @@
 mod private
 {
   use crate::*;
-  use action;
+  // use action;
   use error::untyped::{ Error };
 
   /// Generates header to main Readme.md file.
   // qqq : typed error
   pub fn readme_header_renew() -> error::untyped::Result< () >
   {
-    match action::readme_header_renew
+    match crate::action::main_header::action
     (
       CrateDir::transitive_try_from::< AbsolutePath >( CurrentPath )?
     )
diff --git a/module/move/willbe/src/command/readme_headers_renew.rs b/module/move/willbe/src/command/readme_headers_renew.rs
index 9a79a2b144..3f7af310a7 100644
--- a/module/move/willbe/src/command/readme_headers_renew.rs
+++ b/module/move/willbe/src/command/readme_headers_renew.rs
@@ -1,8 +1,8 @@
 mod private
 {
   use crate::*;
-  use action;
-  use error::{ err };
+  // use action;
+  // use error::{ err };
   use std::fmt::{ Display, Formatter };
 
   #[ derive( Debug, Default ) ]
@@ -64,7 +64,6 @@ mod private
     }
   }
 
-
   /// Aggregates two commands: `generate_modules_headers` & `generate_main_header`
   pub fn readme_headers_renew() -> error::untyped::Result< () > // qqq : use typed error
   {
@@ -73,7 +72,7 @@ mod private
     let crate_dir = CrateDir::transitive_try_from::< AbsolutePath >( CurrentPath )?;
     let mut fail = false;
 
-    match action::readme_header_renew( crate_dir.clone() )
+    match crate::action::main_header::action( crate_dir.clone() )
     {
       Ok( r ) =>
       {
@@ -103,7 +102,7 @@ mod private
     if fail
     {
       eprintln!( "{report}" );
-      Err( err!( "Something went wrong" ) )
+      Err( error::untyped::format_err!( "Something went wrong" ) )
     }
     else
     {
diff --git a/module/move/willbe/src/command/workspace_renew.rs b/module/move/willbe/src/command/workspace_renew.rs
index 7baa1515f6..6e43d29eea 100644
--- a/module/move/willbe/src/command/workspace_renew.rs
+++ b/module/move/willbe/src/command/workspace_renew.rs
@@ -23,7 +23,7 @@ mod private
   {
     let WorkspaceNewProperties { repository_url, branches } = o.props.try_into()?;
     let template = WorkspaceTemplate::default();
-    action::workspace_renew
+    action::workspace_renew::action
     (
       &std::env::current_dir()?,
       template,
diff --git a/module/move/willbe/src/entity/channel.rs b/module/move/willbe/src/entity/channel.rs
index cb45418c06..65fe6b7716 100644
--- a/module/move/willbe/src/entity/channel.rs
+++ b/module/move/willbe/src/entity/channel.rs
@@ -61,7 +61,7 @@ mod private
     .bin_path( program )
     .args( options.into_iter().map( OsString::from ).collect::< Vec< _ > >() )
     .current_path( path.as_ref().to_path_buf() )
-    .run().map_err::< Error, _ >( | report | err!( report.to_string() ) )?;
+    .run().map_err::< Error, _ >( | report | error::untyped::format_err!( report.to_string() ) )?;
 
     let list = report
     .out
diff --git a/module/move/willbe/src/entity/publish.rs b/module/move/willbe/src/entity/publish.rs
index ed1e336129..497ee6c90f 100644
--- a/module/move/willbe/src/entity/publish.rs
+++ b/module/move/willbe/src/entity/publish.rs
@@ -161,7 +161,7 @@ mod private
       .collect();
       for wanted in &self.roots
       {
-        let list = action::list
+        let list = action::list_all
         (
           action::list::ListOptions::former()
           .path_to_manifest( wanted.clone() )
diff --git a/module/move/willbe/src/tool/cargo.rs b/module/move/willbe/src/tool/cargo.rs
index 71590ecd45..4e0bd9a330 100644
--- a/module/move/willbe/src/tool/cargo.rs
+++ b/module/move/willbe/src/tool/cargo.rs
@@ -6,8 +6,8 @@ mod private
 
   use std::ffi::OsString;
   use std::path::PathBuf;
-  use error::err;
-  use error::untyped::format_err;
+  // use error::err;
+  // use error::untyped::format_err;
   use former::Former;
   use process_tools::process;
   // use process_tools::process::*;
@@ -118,7 +118,7 @@ mod private
       .bin_path( program )
       .args( options.into_iter().map( OsString::from ).collect::< Vec< _ > >() )
       .current_path( args.path )
-      .run().map_err( | report | err!( report.to_string() ) )
+      .run().map_err( | report | error::untyped::format_err!( report.to_string() ) )
     }
   }
 
@@ -197,11 +197,11 @@ mod private
       }
       if args.retry_count > 0
       {
-        Err( format_err!( "It took {} attempts, but still failed. Here are the errors:\n{}", args.retry_count + 1, results.into_iter().map( | r | format!( "- {r}" ) ).collect::< Vec< _ > >().join( "\n" ) ) )
+        Err( error::untyped::format_err!( "It took {} attempts, but still failed. Here are the errors:\n{}", args.retry_count + 1, results.into_iter().map( | r | format!( "- {r}" ) ).collect::< Vec< _ > >().join( "\n" ) ) )
       }
       else
       {
-        Err( results.remove( 0 ) ).map_err( | report | err!( report.to_string() ) )
+        Err( results.remove( 0 ) ).map_err( | report | error::untyped::format_err!( report.to_string() ) )
       }
     }
   }
diff --git a/module/move/willbe/src/tool/collection.rs b/module/move/willbe/src/tool/collection.rs
deleted file mode 100644
index edd7bec8c8..0000000000
--- a/module/move/willbe/src/tool/collection.rs
+++ /dev/null
@@ -1,12 +0,0 @@
-/// Internal namespace.
-mod private
-{
-}
-
-crate::mod_interface!
-{
-
-  use ::collection_tools;
-  own use ::collection_tools::own::*;
-
-}
diff --git a/module/move/willbe/src/tool/error.rs b/module/move/willbe/src/tool/error.rs
deleted file mode 100644
index bc00b92ba9..0000000000
--- a/module/move/willbe/src/tool/error.rs
+++ /dev/null
@@ -1,21 +0,0 @@
-/// Internal namespace.
-#[ allow( unused_imports ) ]
-mod private
-{
-  use crate::tool::*;
-  use ::error_tools::own::*;
-
-}
-
-crate::mod_interface!
-{
-  // #![ debug ]
-
-  use ::error_tools;
-  own use ::error_tools::own::*;
-
-  // exposed use ErrWith;
-  // exposed use ResultWithReport;
-  // exposed use ::error_tools::Result;
-
-}
diff --git a/module/move/willbe/src/tool/git.rs b/module/move/willbe/src/tool/git.rs
index 828e4d3c64..05b582cd8a 100644
--- a/module/move/willbe/src/tool/git.rs
+++ b/module/move/willbe/src/tool/git.rs
@@ -7,7 +7,7 @@ mod private
   use std::ffi::OsString;
   use std::path::Path;
   use process_tools::process::*;
-  use error::err;
+  // use error::err;
   // qqq : group dependencies
 
   /// Adds changes to the Git staging area.
@@ -56,7 +56,7 @@ mod private
       .bin_path( program )
       .args( args.into_iter().map( OsString::from ).collect::< Vec< _ > >() )
       .current_path( path.as_ref().to_path_buf() )
-      .run().map_err( | report | err!( report.to_string() ) )
+      .run().map_err( | report | error::untyped::format_err!( report.to_string() ) )
     }
   }
 
@@ -102,7 +102,7 @@ mod private
       .bin_path( program )
       .args( args.into_iter().map( OsString::from ).collect::< Vec< _ > >() )
       .current_path( path.as_ref().to_path_buf() )
-      .run().map_err( | report | err!( report.to_string() ) )
+      .run().map_err( | report | error::untyped::format_err!( report.to_string() ) )
     }
   }
 
@@ -148,7 +148,7 @@ mod private
       .bin_path( program )
       .args( args.into_iter().map( OsString::from ).collect::< Vec< _ > >() )
       .current_path( path.as_ref().to_path_buf() )
-      .run().map_err( | report | err!( report.to_string() ) )
+      .run().map_err( | report | error::untyped::format_err!( report.to_string() ) )
     }
   }
 
@@ -173,7 +173,7 @@ mod private
   where
     P : AsRef< Path >,
   {
-    if commits_count < 1 { return Err( err!( "Cannot reset, the count of commits must be greater than 0" ) ) }
+    if commits_count < 1 { return Err( error::untyped::format_err!( "Cannot reset, the count of commits must be greater than 0" ) ) }
     let ( program, args ) : ( _, Vec< _ > ) =
     (
       "git",
@@ -205,7 +205,7 @@ mod private
       .bin_path( program )
       .args( args.into_iter().map( OsString::from ).collect::< Vec< _ > >() )
       .current_path( path.as_ref().to_path_buf() )
-      .run().map_err( | report | err!( report.to_string() ) )
+      .run().map_err( | report | error::untyped::format_err!( report.to_string() ) )
     }
   }
 
@@ -232,7 +232,7 @@ mod private
     .bin_path( program )
     .args( args.into_iter().map( OsString::from ).collect::< Vec< _ > >() )
     .current_path( path.as_ref().to_path_buf() )
-    .run().map_err( | report | err!( report.to_string() ) )
+    .run().map_err( | report | error::untyped::format_err!( report.to_string() ) )
   }
 }
 
diff --git a/module/move/willbe/src/tool/mod.rs b/module/move/willbe/src/tool/mod.rs
index 719b616b4b..7864cdc660 100644
--- a/module/move/willbe/src/tool/mod.rs
+++ b/module/move/willbe/src/tool/mod.rs
@@ -8,12 +8,15 @@ crate::mod_interface!
   orphan use super::cargo;
 
   /// Function and structures to work with collections.
-  layer collection;
-  orphan use super::collection;
+  // layer collection;
+  // orphan use super::collection;
+  use ::collection_tools;
+  // own use ::collection_tools::own::*;
 
   /// Errors handling.
-  layer error;
-  orphan use super::error;
+  // layer error;
+  // orphan use super::error;
+  use ::error_tools;
 
   /// Operate over files.
   layer files;
diff --git a/module/move/willbe/tests/inc/action_tests/cicd_renew.rs b/module/move/willbe/tests/inc/action_tests/cicd_renew.rs
index ffbbe5b570..75370b0db5 100644
--- a/module/move/willbe/tests/inc/action_tests/cicd_renew.rs
+++ b/module/move/willbe/tests/inc/action_tests/cicd_renew.rs
@@ -90,7 +90,7 @@ fn default_case()
   };
 
   // Act
-  _ = action::cicd_renew( &temp ).unwrap();
+  _ = action::cicd_renew::action( &temp ).unwrap();
   dbg!( &file_path );
 
   // Assert
diff --git a/module/move/willbe/tests/inc/action_tests/features.rs b/module/move/willbe/tests/inc/action_tests/features.rs
index 37a4b63cae..ea0e4e80a0 100644
--- a/module/move/willbe/tests/inc/action_tests/features.rs
+++ b/module/move/willbe/tests/inc/action_tests/features.rs
@@ -24,7 +24,7 @@ fn package_no_features()
   .form();
 
   // Act
-  let report = willbe::action::features( options ).unwrap().to_string();
+  let report = willbe::action::features::orphan::features( options ).unwrap().to_string();
 
   // Assert
   assert!( report.contains(
@@ -43,7 +43,7 @@ fn package_features()
   .form();
 
   // Act
-  let report = willbe::action::features( options ).unwrap().to_string();
+  let report = willbe::action::features::orphan::features( options ).unwrap().to_string();
 
   // Assert
   assert!( report.contains(
@@ -66,7 +66,7 @@ fn package_features_with_features_deps()
   .form();
 
   // Act
-  let report = willbe::action::features( options ).unwrap().to_string();
+  let report = willbe::action::features::orphan::features( options ).unwrap().to_string();
 
   // Assert
   assert!( report.contains(
@@ -89,7 +89,7 @@ fn workspace_no_features()
   .form();
 
   // Act
-  let report = willbe::action::features( options ).unwrap().to_string();
+  let report = willbe::action::features::orphan::features( options ).unwrap().to_string();
 
   // Assert
   assert!( report.contains(
@@ -118,7 +118,7 @@ fn workspace_features()
   .form();
 
   // Act
-  let report = willbe::action::features( options ).unwrap().to_string();
+  let report = willbe::action::features::orphan::features( options ).unwrap().to_string();
 
   // Assert
   assert!( report.contains(
@@ -156,7 +156,7 @@ fn workspace_features_with_features_deps()
   .form();
 
   // Act
-  let report = willbe::action::features( options ).unwrap().to_string();
+  let report = willbe::action::features::orphan::features( options ).unwrap().to_string();
 
   // Assert
   assert!( report.contains(
diff --git a/module/move/willbe/tests/inc/action_tests/list/data.rs b/module/move/willbe/tests/inc/action_tests/list/data.rs
index 423baf654c..9100cf5dfb 100644
--- a/module/move/willbe/tests/inc/action_tests/list/data.rs
+++ b/module/move/willbe/tests/inc/action_tests/list/data.rs
@@ -44,7 +44,7 @@ mod chain_of_three_packages
     .form();
 
     // Act
-    let output = action::list( args ).unwrap();
+    let output = action::list_all( args ).unwrap();
 
     // Assert
     let ListReport::Tree( trees ) = &output else { panic!( "Expected `Tree` format, but found another" ) };
@@ -85,7 +85,7 @@ mod chain_of_three_packages
     .form();
 
     // Act
-    let output = action::list( args ).unwrap();
+    let output = action::list_all( args ).unwrap();
 
     // Assert
     let ListReport::List( names ) = &output else { panic!("Expected `Topological` format, but found another") };
@@ -106,7 +106,7 @@ mod chain_of_three_packages
       .form();
 
     // Act
-    let output = action::list( args ).unwrap();
+    let output = action::list_all( args ).unwrap();
 
     // Assert
     let ListReport::List( names ) = &output else { panic!( "Expected `Topological` format, but found another" ) };
@@ -145,7 +145,7 @@ mod package_with_remote_dependency
       .form();
 
     // Act
-    let output = action::list( args ).unwrap();
+    let output = action::list_all( args ).unwrap();
 
     // Assert
     let ListReport::Tree( trees ) = &output else { panic!( "Expected `Tree` format, but found another" ) };
@@ -183,7 +183,7 @@ mod package_with_remote_dependency
       .form();
 
     // Act
-    let output = action::list( args ).unwrap();
+    let output = action::list_all( args ).unwrap();
 
     // Assert
     let ListReport::List( names ) = &output else { panic!( "Expected `Topological` format, but found another" ) };
@@ -208,7 +208,7 @@ mod package_with_remote_dependency
       .form();
 
     // Act
-    let output = action::list( args ).unwrap();
+    let output = action::list_all( args ).unwrap();
 
     // Assert
     let ListReport::List( names ) = &output else { panic!( "Expected `Topological` format, but found another" ) };
@@ -242,7 +242,7 @@ mod workspace_with_cyclic_dependency
       .form();
 
     // Act
-    let output = action::list( args ).unwrap();
+    let output = action::list_all( args ).unwrap();
 
     // Assert
     let ListReport::Tree( trees ) = &output else { panic!( "Expected `Tree` format, but found another" ) };
@@ -304,7 +304,7 @@ mod workspace_with_cyclic_dependency
       .form();
 
     // Act
-    let output = action::list( args );
+    let output = action::list_all( args );
 
     // Assert
 
diff --git a/module/move/willbe/tests/inc/action_tests/main_header.rs b/module/move/willbe/tests/inc/action_tests/main_header.rs
index 82f1b89fba..6f65b44495 100644
--- a/module/move/willbe/tests/inc/action_tests/main_header.rs
+++ b/module/move/willbe/tests/inc/action_tests/main_header.rs
@@ -25,7 +25,7 @@ fn tag_shout_stay()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
 
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
 
@@ -45,7 +45,7 @@ fn branch_cell()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
 
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
 
@@ -64,7 +64,7 @@ fn discord_cell()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
 
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
 
@@ -83,7 +83,7 @@ fn gitpod_cell()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
 
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
 
@@ -102,7 +102,7 @@ fn docs_cell()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
 
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
 
@@ -121,7 +121,7 @@ fn without_fool_config()
   let temp = arrange( "single_module_without_master_branch_and_discord" );
 
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
 
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
 
@@ -141,13 +141,13 @@ fn idempotency()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
   let mut actual1 = String::new();
   _ = file.read_to_string( &mut actual1 ).unwrap();
   drop( file );
 
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "Readme.md" ) ).unwrap();
   let mut actual2 = String::new();
   _ = file.read_to_string( &mut actual2 ).unwrap();
@@ -164,5 +164,5 @@ fn without_needed_config()
   // Arrange
   let temp = arrange( "variadic_tag_configurations" );
   // Act
-  _ = action::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::readme_header_renew::orphan::readme_header_renew( AbsolutePath::try_from( temp.path() ).unwrap() ).unwrap();
 }
\ No newline at end of file
diff --git a/module/move/willbe/tests/inc/action_tests/readme_health_table_renew.rs b/module/move/willbe/tests/inc/action_tests/readme_health_table_renew.rs
index cce1e9065a..909a186116 100644
--- a/module/move/willbe/tests/inc/action_tests/readme_health_table_renew.rs
+++ b/module/move/willbe/tests/inc/action_tests/readme_health_table_renew.rs
@@ -23,7 +23,7 @@ fn without_any_toml_configurations_test()
   // Arrange
   let temp = arrange( "without_any_toml_configurations" );
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 }
 
 #[ test ]
@@ -33,7 +33,7 @@ fn tags_should_stay()
   let temp = arrange( "without_module_toml_configurations" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -52,7 +52,7 @@ fn stability_experimental_by_default()
   let temp = arrange( "without_module_toml_configurations" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -70,7 +70,7 @@ fn stability_and_repository_from_module_toml()
   let temp = arrange( "without_workspace_toml_configurations" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -101,7 +101,7 @@ fn variadic_tag_configuration_test()
   let temp = arrange( "variadic_tag_configurations" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -121,7 +121,7 @@ fn module_cell()
   let temp = arrange( "full_config" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -139,7 +139,7 @@ fn stability_cell()
   let temp = arrange( "full_config" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -157,7 +157,7 @@ fn branches_cell()
   let temp = arrange( "full_config" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -175,7 +175,7 @@ fn docs_cell()
   let temp = arrange( "full_config" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
@@ -193,7 +193,7 @@ fn sample_cell()
   let temp = arrange( "full_config" );
 
   // Act
-  _  = action::readme_health_table_renew( &temp ).unwrap();
+  _  = action::readme_health_table_renew::orphan::readme_health_table_renew( &temp ).unwrap();
 
   // Assert
   let mut file = std::fs::File::open( temp.path().join( "readme.md" ) ).unwrap();
diff --git a/module/move/willbe/tests/inc/action_tests/readme_modules_headers_renew.rs b/module/move/willbe/tests/inc/action_tests/readme_modules_headers_renew.rs
index db82f365ba..1d4d012d5d 100644
--- a/module/move/willbe/tests/inc/action_tests/readme_modules_headers_renew.rs
+++ b/module/move/willbe/tests/inc/action_tests/readme_modules_headers_renew.rs
@@ -32,7 +32,9 @@ fn tags_should_stay()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  // _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+
   let mut file = std::fs::File::open( temp.path().join( "test_module" ).join( "Readme.md" ) ).unwrap();
 
   let mut actual = String::new();
@@ -51,7 +53,7 @@ fn default_stability()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "test_module" ).join( "Readme.md" ) ).unwrap();
 
   let mut actual = String::new();
@@ -70,7 +72,7 @@ fn docs()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "test_module" ).join( "Readme.md" ) ).unwrap();
 
   let mut actual = String::new();
@@ -88,7 +90,7 @@ fn no_gitpod()
   let temp = arrange("single_module");
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open(temp.path().join("test_module").join("Readme.md")).unwrap();
 
   let mut actual = String::new();
@@ -105,7 +107,7 @@ fn with_gitpod()
   let temp = arrange( "single_module_with_example" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "module" ).join( "test_module" ).join( "Readme.md" ) ).unwrap();
 
   let mut actual = String::new();
@@ -123,7 +125,7 @@ fn discord()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "test_module" ).join( "Readme.md" ) ).unwrap();
 
   let mut actual = String::new();
@@ -141,7 +143,7 @@ fn status()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "test_module" ).join( "Readme.md" ) ).unwrap();
 
   let mut actual = String::new();
@@ -159,13 +161,13 @@ fn idempotency()
   let temp = arrange( "single_module" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "test_module" ).join( "Readme.md" ) ).unwrap();
   let mut actual1 = String::new();
   _ = file.read_to_string( &mut actual1 ).unwrap();
   drop( file );
 
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
   let mut file = std::fs::File::open( temp.path().join( "test_module" ).join( "Readme.md" ) ).unwrap();
   let mut actual2 = String::new();
   _ = file.read_to_string( &mut actual2 ).unwrap();
@@ -180,7 +182,7 @@ fn with_many_members_and_varius_config()
 {
   let temp = arrange( "three_packages" );
 
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
 
   let mut file_b = std::fs::File::open( temp.path().join( "b" ).join( "Readme.md" ) ).unwrap();
   let mut file_c = std::fs::File::open( temp.path().join( "c" ).join( "Readme.md" ) ).unwrap();
@@ -207,5 +209,5 @@ fn without_needed_config()
   let temp = arrange( "variadic_tag_configurations" );
 
   // Act
-  _ = action::readme_modules_headers_renew( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
+  _ = action::main_header::action( CrateDir::try_from( temp.path() ).unwrap() ).unwrap();
 }
diff --git a/module/move/willbe/tests/inc/action_tests/workspace_renew.rs b/module/move/willbe/tests/inc/action_tests/workspace_renew.rs
index 9dbfcea23d..4790c39f25 100644
--- a/module/move/willbe/tests/inc/action_tests/workspace_renew.rs
+++ b/module/move/willbe/tests/inc/action_tests/workspace_renew.rs
@@ -26,7 +26,7 @@ fn default_case()
   create_dir(temp.join("test_project_name" )).unwrap();
 
   // Act
-  _ = workspace_renew( &temp.path().join( "test_project_name" ), WorkspaceTemplate::default(), "https://github.con/Username/TestRepository".to_string(), vec![ "master".to_string() ] ).unwrap();
+  _ = workspace_renew::action( &temp.path().join( "test_project_name" ), WorkspaceTemplate::default(), "https://github.con/Username/TestRepository".to_string(), vec![ "master".to_string() ] ).unwrap();
 
   // Assets
   assert!( temp_path.join( "module" ).exists() );
@@ -57,7 +57,7 @@ fn non_empty_dir()
   let temp = arrange( "single_module" );
 
   // Act
-  let r = workspace_renew( temp.path(), WorkspaceTemplate::default(), "".to_string(), vec![] );
+  let r = workspace_renew::action( temp.path(), WorkspaceTemplate::default(), "".to_string(), vec![] );
 
   // Assert
   assert!( r.is_err() );
diff --git a/module/move/willbe/tests/inc/tool/graph_test.rs b/module/move/willbe/tests/inc/tool/graph_test.rs
index 75a2b29db3..0ad57fa024 100644
--- a/module/move/willbe/tests/inc/tool/graph_test.rs
+++ b/module/move/willbe/tests/inc/tool/graph_test.rs
@@ -3,7 +3,7 @@ use super::*;
 // qqq : for Bohdan : bad. don't import the_module::*
 // use the_module::*;
 use the_module::graph::toposort;
-use collection::HashMap;
+use test_tools::collection::HashMap;
 use petgraph::Graph;
 use willbe::graph::topological_sort_with_grouping;
 
diff --git a/module/postponed/non_std/Cargo.toml b/module/postponed/non_std/Cargo.toml
index 516d197d99..1f684f13cb 100644
--- a/module/postponed/non_std/Cargo.toml
+++ b/module/postponed/non_std/Cargo.toml
@@ -72,7 +72,7 @@ meta_default = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  #"meta_constructors",
   "meta_idents_concat",
 ]
 meta_full = [
@@ -82,7 +82,7 @@ meta_full = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  #"meta_constructors",
   "meta_idents_concat",
 ]
 meta_no_std = [ "wtools/meta_no_std" ]
diff --git a/module/postponed/std_tools/Cargo.toml b/module/postponed/std_tools/Cargo.toml
index 44d29afa00..928fe93678 100644
--- a/module/postponed/std_tools/Cargo.toml
+++ b/module/postponed/std_tools/Cargo.toml
@@ -73,7 +73,7 @@ meta_default = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  #"meta_constructors",
   "meta_idents_concat",
 ]
 meta_full = [
@@ -83,7 +83,7 @@ meta_full = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  #"meta_constructors",
   "meta_idents_concat",
 ]
 meta_no_std = [ "wtools/meta_no_std" ]
diff --git a/module/postponed/std_x/Cargo.toml b/module/postponed/std_x/Cargo.toml
index 5693aa40a1..2ee0a6f55c 100644
--- a/module/postponed/std_x/Cargo.toml
+++ b/module/postponed/std_x/Cargo.toml
@@ -75,7 +75,7 @@ meta_default = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  #"meta_constructors",
   "meta_idents_concat",
 ]
 meta_full = [
@@ -85,7 +85,7 @@ meta_full = [
   "meta_mod_interface",
   # "meta_former",
   # "meta_options",
-  "meta_constructors",
+  #"meta_constructors",
   "meta_idents_concat",
 ]
 meta_no_std = [ "wtools/meta_no_std" ]
diff --git a/module/step/meta/src/module/terminal.rs b/module/step/meta/src/module/terminal.rs
index 93289921c5..4a88acf6a9 100644
--- a/module/step/meta/src/module/terminal.rs
+++ b/module/step/meta/src/module/terminal.rs
@@ -1,4 +1,6 @@
 
+/// Mechanism to include tests only to terminal crate.
+/// It exclude code in terminal module ( crate ), but include for aggregating module ( crate ).
 #[ macro_export ]
 macro_rules! only_for_terminal_module
 {
@@ -8,6 +10,8 @@ macro_rules! only_for_terminal_module
   };
 }
 
+/// Mechanism to include tests only to aggregating crate.
+/// It exclude code in terminal module ( crate ), but include for aggregating module ( crate ).
 #[ macro_export ]
 macro_rules! only_for_aggregating_module
 {
diff --git a/module/step/meta/tests/_conditional/local_module.rs b/module/step/meta/tests/_conditional/local_module.rs
index 93289921c5..4a88acf6a9 100644
--- a/module/step/meta/tests/_conditional/local_module.rs
+++ b/module/step/meta/tests/_conditional/local_module.rs
@@ -1,4 +1,6 @@
 
+/// Mechanism to include tests only to terminal crate.
+/// It exclude code in terminal module ( crate ), but include for aggregating module ( crate ).
 #[ macro_export ]
 macro_rules! only_for_terminal_module
 {
@@ -8,6 +10,8 @@ macro_rules! only_for_terminal_module
   };
 }
 
+/// Mechanism to include tests only to aggregating crate.
+/// It exclude code in terminal module ( crate ), but include for aggregating module ( crate ).
 #[ macro_export ]
 macro_rules! only_for_aggregating_module
 {
diff --git a/module/step/meta/tests/_conditional/wtools.rs b/module/step/meta/tests/_conditional/wtools.rs
index e6bb553f35..ba669c790d 100644
--- a/module/step/meta/tests/_conditional/wtools.rs
+++ b/module/step/meta/tests/_conditional/wtools.rs
@@ -1,4 +1,6 @@
 
+/// Mechanism to include tests only to terminal crate.
+/// It exclude code in terminal module ( crate ), but include for aggregating module ( crate ).
 #[ macro_export ]
 macro_rules! only_for_terminal_module
 {
@@ -7,6 +9,8 @@ macro_rules! only_for_terminal_module
   }
 }
 
+/// Mechanism to include tests only to aggregating crate.
+/// It exclude code in terminal module ( crate ), but include for aggregating module ( crate ).
 #[ macro_export ]
 macro_rules! only_for_aggregating_module
 {