diff --git a/core/check.py b/core/check.py
index d280071..585d3c1 100644
--- a/core/check.py
+++ b/core/check.py
@@ -1,9 +1,11 @@
 import core.checks.executable as exe
 import core.checks.syntax_check as stx
+import core.checks.kind as kind
 import core.checks.version_validity as version
 
 
 def check_package(pkg):
     exe.ExecCheck().run()
     stx.DescriptionCheck(pkg).run()
+    kind.KindCheck(pkg).run()
     version.VersionValidityCheck(pkg).run()
diff --git a/core/checks/base.py b/core/checks/base.py
index 2b3b3e1..115a1b4 100644
--- a/core/checks/base.py
+++ b/core/checks/base.py
@@ -76,6 +76,7 @@ def __init__(self, pkg, items):
     def edit(self, item):
         utils.open_editor(self.pkg.manifest_path)
         self.pkg.manifest = toml.load(self.pkg.manifest_path)
+        self.pkg.is_effective = self.pkg.manifest['kind'] == 'effective'
 
     def write_pkg_manifest(self):
         with open(self.pkg.manifest_path, 'w') as filename:
diff --git a/core/checks/kind.py b/core/checks/kind.py
new file mode 100644
index 0000000..42b3f3c
--- /dev/null
+++ b/core/checks/kind.py
@@ -0,0 +1,60 @@
+import os
+import core.log as log
+import core.checks.base as base
+import core.checks.utils as utils
+
+
+class KindCheck(base.CheckWithManifest):
+    def __init__(self, pkg):
+        super().__init__(pkg, [None])
+
+    def run(self):
+        log.s("Checking package kind")
+        super().run()
+
+    def validate(self, _):
+        length = len(os.listdir(self.pkg.cache))
+        return (self.pkg.is_effective and length != 1) \
+            or (not self.pkg.is_effective and length == 1)
+
+    def show(self, _):
+        if self.pkg.is_effective:
+            log.e("Package is effective but is missing a data.tar.gz")
+        else:
+            log.e("Package is virtual but has a data.tar.gz")
+
+    def diff(self, _):
+        target = 'virtual' if self.pkg.is_effective else 'effective'
+        log.i(f"Package kind would be changed to {target}")
+
+    def fix(self, _):
+        target = 'virtual' if self.pkg.is_effective else 'effective'
+        self.pkg.manifest['kind'] = target
+        self.pkg.is_effective = not self.pkg.is_effective
+        self.write_pkg_manifest()
+
+    def edit(self, _):
+        if self.pkg.is_effective:
+            ans = self._ask_1or2("Would you like to edit the manifest.toml (1) "
+                                 "or to add files to the package (2)? ")
+            if ans == 1:
+                super().edit(_)
+            elif ans == 2:
+                utils.open_shell(self.pkg.cache)
+        else:
+
+            ans = self._ask_1or2("Would you like to edit the manifest.toml (1) "
+                                 "or to remove the files from the package? (2) ")
+            if ans == 1:
+                super().edit(_)
+
+    @staticmethod
+    def _ask_1or2(question):
+        while True:
+            ans = log.q(question)
+            if ans == '1':
+                return 1
+            elif ans == '2':
+                return 2
+            else:
+                log.w("Only recognized answers are 1 and 2")
diff --git a/core/package.py b/core/package.py
index 2a91e9a..bdc642b 100644
--- a/core/package.py
+++ b/core/package.py
@@ -38,6 +38,8 @@ def wrap(self):
         self.show_manifest()
         if self.is_effective:
             self.create_data_tar()
+        else:
+            log.i("Ignoring data.tar.gz creation phase because package is virtual")
         self.create_nest_file()
 
     def update_manifest_toml_wrap_date(self):
@@ -75,6 +77,7 @@ def create_nest_file(self):
                 os.remove('data.tar.gz')
         new_path = f'{self.npf_path}.new'
         os.rename(os.path.join(self.cache, new_nest_file_path), new_path)
+        log.s(f"New NPF is located at {new_path}")
 
     def show_manifest(self):
         m = self.manifest