--- mercurial-4.8.1/setup.py
+++ mercurial-4.8.1/setup.py
@@ -983,12 +983,6 @@
               ['hgext/fsmonitor/pywatchman/bser.c']),
     ]
 
-sys.path.insert(0, 'contrib/python-zstandard')
-import setup_zstd
-extmodules.append(setup_zstd.get_c_extension(
-    name='mercurial.zstd',
-    root=os.path.abspath(os.path.dirname(__file__))))
-
 try:
     from distutils import cygwinccompiler