diff --git a/nyacme/__main__.py b/nyacme/__main__.py
index 53743d7..99954e7 100644
--- a/nyacme/__main__.py
+++ b/nyacme/__main__.py
@@ -66,7 +66,7 @@ def main() -> None:
             domain_key = os.path.join(args.output, f'{domain}/cert.pem.key')
             domain_pem = os.path.join(args.output, f'{domain}/cert.pem')
 
-            shutil.copy2(private_key, domain_key)
+            os.link(private_key, domain_key)
             # TODO: add user/group to config
             shutil.chown(domain_key, 'acme', 'acme')
             os.chmod(domain_key, 0o440)
@@ -74,8 +74,8 @@ def main() -> None:
             all_pem = os.path.join(args.output, f'all/{domain}.pem')
             all_key = os.path.join(args.output, f'all/{domain}.pem.key')
 
-            shutil.copy2(domain_pem, all_pem)
-            shutil.copy2(domain_key, all_key)
+            os.link(domain_pem, all_pem)
+            os.link(domain_key, all_key)
 
     if acquired:
         for cmd in config.post_acquire: