diff --git a/build.py b/build.py
index addce8b..a2b823a 100644
--- a/build.py
+++ b/build.py
@@ -1,4 +1,5 @@
 import shutil
+import importlib.util
 from pathlib import Path
 import PyInstaller.__main__
 import typer
@@ -22,6 +23,25 @@ def build(build: bool = True, copy: bool = True, test: bool = False, dest: str |
         if test:
             print("Building Windows test one-file bundle with PyInstaller")
             # On Windows use ';' as add-data separator (src;dest)
+            add_data_args = ["--add-data", "icon;icon"]
+
+            # Try to include dicognito package data (release_notes.md) which
+            # PyInstaller may miss. This prevents runtime FileNotFoundError for
+            # dicognito/release_notes.md when the package expects the file at runtime.
+            try:
+                spec = importlib.util.find_spec("dicognito")
+                if spec and spec.submodule_search_locations:
+                    dicognito_path = Path(spec.submodule_search_locations[0])
+                    release_notes = dicognito_path / "release_notes.md"
+                    if release_notes.exists():
+                        # PyInstaller on Windows expects 'src;dest'
+                        add_data_args += ["--add-data", f"{str(release_notes)};dicognito"]
+                    else:
+                        # include whole package folder if the single file wasn't found
+                        add_data_args += ["--add-data", f"{str(dicognito_path)};dicognito"]
+            except Exception as e:
+                print(f"Warning: couldn't locate dicognito package: {e}")
+
             PyInstaller.__main__.run([
                 str(project_root / "nice.py"),
                 "--onefile",
@@ -33,8 +53,8 @@ def build(build: bool = True, copy: bool = True, test: bool = False, dest: str |
                 str(project_root / "build" / "test"),
                 "--specpath",
                 str(project_root / "build" / "specs"),
-                "--add-data",
-                "icon;icon",
+            ] + add_data_args + [
+                # add some common hidden imports that PyInstaller sometimes misses
                 "--hidden-import",
                 "bs4",
                 "--hidden-import",