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 39237fcb12..2be1eab6a8 100644
--- a/module/move/willbe/src/action/readme_modules_headers_renew.rs
+++ b/module/move/willbe/src/action/readme_modules_headers_renew.rs
@@ -12,7 +12,7 @@ mod private
   use std::borrow::Cow;
   use std::fs::{ OpenOptions };
   use std::io::{ Read, Seek, SeekFrom, Write };
-  use std::path::{Path, PathBuf};
+  use std::path::PathBuf;
   use convert_case::{ Case, Casing };
   use regex::Regex;
   use crate::action::readme_health_table_renew::find_example_file;
diff --git a/module/move/willbe/src/entity/features.rs b/module/move/willbe/src/entity/features.rs
index a292b131b1..81c1452180 100644
--- a/module/move/willbe/src/entity/features.rs
+++ b/module/move/willbe/src/entity/features.rs
@@ -2,7 +2,6 @@ mod private
 {
   use crate::*;
   use std::collections::{ BTreeSet, HashSet };
-  use error_tools::err;
   // aaa : for Petro : don't use cargo_metadata and Package directly, use facade
   // aaa : ✅
   use error_tools::for_app::{ bail, Result };
diff --git a/module/move/willbe/src/entity/manifest.rs b/module/move/willbe/src/entity/manifest.rs
index 619a5bab8c..0b5405bf48 100644
--- a/module/move/willbe/src/entity/manifest.rs
+++ b/module/move/willbe/src/entity/manifest.rs
@@ -7,7 +7,7 @@ pub( crate ) mod private
   {
     io::{ self, Read },
     fs,
-    path::Path,
+    path::{ Path, PathBuf },
   };
   use wtools::error::
   {
@@ -53,6 +53,21 @@ pub( crate ) mod private
       Ok( Self( crate_dir_path ) )
     }
   }
+  
+  impl TryFrom< PathBuf > for CrateDir
+  {
+    type Error = CrateDirError;
+
+    fn try_from( crate_dir_path : PathBuf ) -> Result< Self, Self::Error >
+    {
+      if !crate_dir_path.join( "Cargo.toml" ).exists()
+      {
+        return Err( CrateDirError::Validation( "The path is not a crate directory path".into() ) );
+      }
+
+      Ok( Self( AbsolutePath::try_from( crate_dir_path ).unwrap() ) )
+    }
+  }
 
   impl CrateDir
   {
diff --git a/module/move/willbe/tests/inc/entity/diff.rs b/module/move/willbe/tests/inc/entity/diff.rs
new file mode 100644
index 0000000000..b3362ee64d
--- /dev/null
+++ b/module/move/willbe/tests/inc/entity/diff.rs
@@ -0,0 +1,98 @@
+use crate::*;
+
+use std::path::{ Path, PathBuf };
+use assert_fs::{ TempDir, prelude::* };
+use crates_tools::CrateArchive;
+use the_module::*;
+use _path::AbsolutePath;
+use package::Package;
+use diff::crate_diff;
+use the_module::version::{ Version, BumpOptions, version_bump };
+
+const TEST_MODULE_PATH : &str = "../../test/";
+
+#[ test ]
+fn no_changes()
+{
+  let tmp = &TempDir::new().unwrap();
+  let package_path = package_path( "c" );
+  
+  let left = prepare( tmp, "left", &package_path );
+  let left_crate = crate_file_path( &left );
+  let left_archive = CrateArchive::read( &left_crate ).unwrap();
+  
+  let right = prepare( tmp, "right", &package_path );
+  let right_crate = crate_file_path( &right );
+  let right_archive = CrateArchive::read( &right_crate ).unwrap();
+  
+  let has_changes = crate_diff( &left_archive, &right_archive ).exclude( diff::PUBLISH_IGNORE_LIST ).has_changes();
+  
+  assert!( !has_changes );
+}
+
+#[ test ]
+fn with_changes()
+{
+  let tmp = &TempDir::new().unwrap();
+  let package_path = package_path( "c" );
+
+  let left =
+  {
+    let left = prepare( tmp, "left", &package_path );
+    let left_crate = crate_file_path( &left );
+    CrateArchive::read( &left_crate ).unwrap()
+  };
+
+  let right =
+  {
+    let right = prepare( tmp, "right", &package_path );
+
+    let absolute = AbsolutePath::try_from( right.as_path() ).unwrap();
+    let right_package = Package::try_from( absolute ).unwrap();
+    let right_version = Version::try_from( &right_package.version().unwrap() ).unwrap();
+
+    let bump_options = BumpOptions
+    {
+      crate_dir : CrateDir::try_from( right.clone() ).unwrap(),
+      old_version : right_version.clone(),
+      new_version : right_version.bump(),
+      dependencies : vec![],
+      dry : false,
+    };
+    version_bump( bump_options ).unwrap();
+
+    let right_crate = crate_file_path( &right );
+    CrateArchive::read( &right_crate ).unwrap()
+  };
+
+  let has_changes = crate_diff( &left, &right ).exclude( diff::PUBLISH_IGNORE_LIST ).has_changes();
+
+  assert!( has_changes );
+}
+
+fn package_path< P : AsRef< Path > >( path : P ) -> PathBuf
+{
+  let root_path = Path::new( env!( "CARGO_MANIFEST_DIR" ) ).join( TEST_MODULE_PATH );
+  root_path.join( path )
+}
+
+fn prepare( tmp : &TempDir, name : &str, manifest_dir_path : &Path ) -> PathBuf
+{
+  let dir = tmp.child( name );
+  dir.create_dir_all().unwrap();
+  dir.copy_from( manifest_dir_path, &[ "**" ] ).unwrap();
+
+  dir.to_path_buf()
+}
+
+fn crate_file_path( manifest_dir_path : &Path ) -> PathBuf
+{
+  _ = cargo::pack( cargo::PackOptions::former().path( manifest_dir_path ).dry( false ).form() ).expect( "Failed to package a package" );
+
+  let absolute = AbsolutePath::try_from( manifest_dir_path ).unwrap();
+  let package = Package::try_from( absolute ).unwrap();
+  manifest_dir_path
+    .join( "target" )
+    .join( "package" )
+    .join( format!( "{}-{}.crate", package.name().unwrap(), package.version().unwrap() ) )
+}
diff --git a/module/move/willbe/tests/inc/entity/mod.rs b/module/move/willbe/tests/inc/entity/mod.rs
index d86862bb87..58ee035a97 100644
--- a/module/move/willbe/tests/inc/entity/mod.rs
+++ b/module/move/willbe/tests/inc/entity/mod.rs
@@ -1,9 +1,6 @@
 use super::*;
 
+pub mod dependencies;
+pub mod diff;
 pub mod features;
-
 pub mod version;
-
-pub mod publish_need;
-
-pub mod dependencies;
\ No newline at end of file
diff --git a/module/move/willbe/tests/inc/entity/publish_need.rs b/module/move/willbe/tests/inc/entity/publish_need.rs
deleted file mode 100644
index 59f4a97828..0000000000
--- a/module/move/willbe/tests/inc/entity/publish_need.rs
+++ /dev/null
@@ -1,134 +0,0 @@
-use super::*;
-
-use std::
-{
-  io::Write,
-  path::{ Path, PathBuf },
-};
-
-use assert_fs::prelude::*;
-use the_module::
-{
-  package::{ publish_need, Package },
-  _path::AbsolutePath,
-  manifest,
-  version,
-  cargo
-};
-
-const TEST_MODULE_PATH : &str = "../../test/";
-
-fn package_path< P : AsRef< Path > >( path : P ) -> PathBuf
-{
-  let root_path = Path::new( env!( "CARGO_MANIFEST_DIR" ) ).join( TEST_MODULE_PATH );
-  root_path.join( path )
-}
-
-fn package< P : AsRef< Path > >( path : P ) -> Package
-{
-  let path = path.as_ref();
-  _ = cargo::pack( cargo::PackOptions::former().path( path.to_path_buf() ).dry( false ).form() ).expect( "Failed to package a package" );
-  let absolute = AbsolutePath::try_from( path ).unwrap();
-
-  Package::try_from( absolute ).unwrap()
-}
-
-// published the same as local
-#[ test ]
-fn no_changes()
-{
-  // Arrange
-  // aaa : for Bohdan : make helper function returning package_path. reuse it for all relevant tests
-  // aaa : use `package_path` function
-  let package_path = package_path( "c" );
-
-  _ = cargo::pack( cargo::PackOptions::former().path( package_path.clone() ).dry( false ).form() ).expect( "Failed to package a package" );
-  let absolute = AbsolutePath::try_from( package_path ).unwrap();
-  let package = Package::try_from( absolute ).unwrap();
-
-  // Act
-  let publish_needed = publish_need( &package, None ).unwrap();
-
-  // Assert
-  assert!( !publish_needed );
-}
-
-// version bumped => publish required
-#[ test ]
-fn with_changes()
-{
-  // Arrange
-  let package_path = package_path( "c" );
-
-  let temp = assert_fs::TempDir::new().unwrap();
-  temp.copy_from( &package_path, &[ "**" ] ).unwrap();
-
-  let absolute = AbsolutePath::try_from( temp.as_ref() ).unwrap();
-  let mut manifest = manifest::open( absolute ).unwrap();
-  version::bump( &mut manifest, false ).unwrap();
-
-  _ = cargo::pack( cargo::PackOptions::former().path( temp.path().to_path_buf() ).dry( false ).form() ).expect( "Failed to package a package" );
-
-  let absolute = AbsolutePath::try_from( temp.as_ref() ).unwrap();
-  let package = Package::try_from( absolute ).unwrap();
-
-  // Act
-  let publish_needed = publish_need( &package, None ).unwrap();
-
-  // Assert
-  assert!( publish_needed );
-}
-
-// c(update) -> b(re-publish) -> a(re-publish)
-#[ test ]
-fn cascade_with_changes()
-{
-  let abc = [ "a", "b", "c" ].into_iter().map( package_path ).map( package ).collect::< Vec< _ > >();
-  let [ a, b, c ] = abc.as_slice() else { unreachable!() };
-  if ![ c, b, a ].into_iter().inspect( | x | { dbg!( x.name().unwrap() ); } ).map( | a | publish_need( a, None ) ).inspect( | x | { dbg!(x); } ).all( | p | !p.expect( "There was an error verifying whether the package needs publishing or not" ) )
-  {
-    panic!( "The packages must be up-to-dated" );
-  }
-  let temp = assert_fs::TempDir::new().unwrap();
-  let temp_module = temp.child( "module" );
-  std::fs::create_dir( &temp_module ).unwrap();
-  temp_module.child( "a" ).copy_from( a.manifest_path().parent().unwrap(), &[ "**" ] ).unwrap();
-  temp_module.child( "b" ).copy_from( b.manifest_path().parent().unwrap(), &[ "**" ] ).unwrap();
-  temp_module.child( "c" ).copy_from( c.manifest_path().parent().unwrap(), &[ "**" ] ).unwrap();
-  let a_temp_path = temp_module.join( "a" );
-  let b_temp_path = temp_module.join( "b" );
-  let c_temp_path = temp_module.join( "c" );
-
-  let mut cargo_toml = std::fs::File::create( temp.join( "Cargo.toml" ) ).unwrap();
-  write!( cargo_toml, r#"
-[workspace]
-resolver = "2"
-members = [
-    "module/*",
-]
-[workspace.dependencies.test_experimental_a]
-version = "*"
-path = "module/a"
-default-features = true
-[workspace.dependencies.test_experimental_b]
-version = "*"
-path = "module/b"
-default-features = true
-[workspace.dependencies.test_experimental_c]
-version = "*"
-path = "module/c"
-default-features = true
-"# ).unwrap();
-
-  let absolute = AbsolutePath::try_from( c_temp_path.join( "Cargo.toml" ) ).unwrap();
-  let mut manifest = manifest::open( absolute ).unwrap();
-  version::bump( &mut manifest, false ).unwrap();
-
-  let c_temp = package( c_temp_path );
-  let b_temp = package( b_temp_path );
-  let a_temp = package( a_temp_path );
-
-  assert!( publish_need( &c_temp, None ).unwrap() );
-  assert!( publish_need( &b_temp, None ).unwrap() );
-  assert!( publish_need( &a_temp, None ).unwrap() );
-}
diff --git a/module/move/willbe/tests/inc/package.rs b/module/move/willbe/tests/inc/package.rs
index 08b2f36f93..935069b5e6 100644
--- a/module/move/willbe/tests/inc/package.rs
+++ b/module/move/willbe/tests/inc/package.rs
@@ -1,12 +1,12 @@
-use super::*;
-use the_module::
-{
-  Workspace,
-  _path::AbsolutePath,
-  package::PublishPlan,
-};
-use willbe::package::perform_packages_publish;
-
+// use super::*;
+// use the_module::
+// {
+//   Workspace,
+//   _path::AbsolutePath,
+//   package::PublishPlan,
+// };
+// use willbe::package::perform_packages_publish;
+// 
 // #[ test ]
 // fn plan_publish_many_packages()
 // {