diff --git a/fftcg/__init__.py b/fftcg/__init__.py
index 9c9ce3d..96f71c1 100644
--- a/fftcg/__init__.py
+++ b/fftcg/__init__.py
@@ -1,3 +1,4 @@
-from book import Book
-from opus import Opus
+from .book import Book
+from .opus import Opus
 
+__all__ = ["Book", "Opus"]
diff --git a/fftcg/book.py b/fftcg/book.py
index 394d569..163e4d6 100644
--- a/fftcg/book.py
+++ b/fftcg/book.py
@@ -2,8 +2,8 @@ import logging
 
 from PIL import Image
 
-from cards import Cards
-from imageloader import ImageLoader
+from .cards import Cards
+from .imageloader import ImageLoader
 
 
 def chunks(whole: list[any], chunk_size) -> list:
diff --git a/fftcg/cards.py b/fftcg/cards.py
index da609ad..997c936 100644
--- a/fftcg/cards.py
+++ b/fftcg/cards.py
@@ -1,6 +1,6 @@
 import requests
 
-from card import Card
+from .card import Card
 
 
 class Cards(list[Card]):
diff --git a/fftcg/opus.py b/fftcg/opus.py
index 3144d20..2c9aeda 100644
--- a/fftcg/opus.py
+++ b/fftcg/opus.py
@@ -2,7 +2,7 @@ import logging
 
 import roman
 
-from cards import Cards
+from .cards import Cards
 
 
 class Opus(Cards):
diff --git a/main.py b/main.py
index 6d0c743..bd95bd7 100755
--- a/main.py
+++ b/main.py
@@ -3,7 +3,7 @@ import argparse
 import logging
 import os
 
-from fftcg import Book, Opus
+import fftcg
 
 # constants
 GRID = 7, 10  # default in TTsim: 7 rows, 10 columns
@@ -43,8 +43,8 @@ def main() -> None:
     os.chdir("out")
 
     # main program
-    opus = Opus(args.opus_id)
-    book = Book(opus, GRID, RESOLUTION, "eg", args.num_threads)
+    opus = fftcg.Opus(args.opus_id)
+    book = fftcg.Book(opus, GRID, RESOLUTION, "eg", args.num_threads)
     book.save(f"{opus.name}_{{}}.jpg")
 
     # bye